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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 14A
(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.      )

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Filed by a Party other than the Registrant o

Check the appropriate box:

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Preliminary Proxy Statement

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Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

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Definitive Proxy Statement

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Definitive Additional Materials

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Soliciting Material under §240.14a-12

 

ALKERMES PUBLIC LIMITED COMPANY
(Name of Registrant as Specified In Its Charter)

 
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

 
 
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Amount Previously Paid:
         
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GRAPHIC

Registered in Ireland—No. 498284
Connaught House
1 Burlington Road
Dublin 4, Ireland


NOTICE OF 2012 ANNUAL GENERAL MEETING OF SHAREHOLDERS

TO BE HELD AUGUST 1, 2012

To the Shareholders:

        The 2012 Annual General Meeting of Alkermes plc (the "Company" or "Alkermes"), a company incorporated under the laws of Ireland, will be held on August 1, 2012 at 12:30 p.m., local time, at the Company's offices at Connaught House, 1 Burlington Road, Dublin 4, Ireland, for the following purposes:

        Proposal 1 relates solely to the election of two Class 1 directors nominated by the Board of Directors and does not include any other matters relating to the election of directors, including without limitation, the election of directors nominated by any shareholder of the Company. Proposals 1 through 3 and proposals 5 and 6 are ordinary resolutions, requiring a simple majority of the votes cast at the meeting. A plurality of the votes cast for proposal 4 will determine the frequency of the advisory vote on executive compensation. These items of business are more fully described in the proxy statement accompanying this notice.

        During the Annual General Meeting, management will present the Company's Irish Statutory Accounts for the fiscal year ended March 31, 2012, and the reports of the auditors thereon.

        The board of directors has fixed June 15, 2012 as the record date for the Annual General Meeting. Only shareholders who are registered as shareholders as of the close of trading on the NASDAQ

Global Select Market on the record date will be entitled to notice of, and to vote at, the Annual General Meeting.

        Any shareholder entitled to attend and vote at the meeting is entitled to appoint a proxy or proxies to attend, speak and vote on such shareholder's behalf. Such proxy need not be a shareholder of the Company. If you wish to appoint as proxy any person other than the individuals specified in the Company's proxy card, please contact the Company Secretary.

        Proxy Materials for the Annual General Meeting of Shareholders to be held on August 1, 2012 at 12:30 p.m. local time at the Company's offices at Connaught House, 1 Burlington Road, Dublin 4, Ireland, are available at: www.edocumentview.com/alks.

        On or around June 22, 2012, we will mail to our shareholders (other than those who previously requested electronic delivery) the Notice of Annual General Meeting of Shareholders, our Proxy Statement, our Proxy Card, our Irish Statutory Accounts for the fiscal year ended March 31, 2012, and our Annual Report on Form 10-K for the fiscal year ended March 31, 2012 (collectively, the "Proxy Materials"). Note that if you have previously elected to receive our Proxy Materials electronically, you will continue to receive these materials via email unless you elect otherwise.

By Order of the Board of Directors

GRAPHIC

KATHRYN L. BIBERSTEIN
Secretary

Dublin, Ireland
June 19, 2012

        You are cordially invited to attend the meeting in person. The presence at the meeting, in person or by proxy, of one or more shareholders who hold shares representing not less than a majority of the issued and outstanding shares entitled to vote at the meeting shall constitute a quorum. Your vote is important. Whether or not you expect to attend the meeting, please complete, date, sign and return the enclosed proxy, or vote over the telephone or the Internet as instructed in these materials, as promptly as possible in order to ensure your representation at the meeting. A return envelope (which is postage prepaid if mailed in the United States) is enclosed for your convenience. Even if you have voted by proxy, you may still vote in person if you attend the meeting. Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to vote at the meeting, you must obtain a proxy issued in your name from that record holder.

SIG


Registered in Ireland—No. 498284
Connaught House
1 Burlington Road
Dublin 4, Ireland


PROXY STATEMENT
FOR THE ANNUAL GENERAL MEETING OF SHAREHOLDERS
AUGUST 1, 2012

Introduction

        On May 9, 2011, Alkermes plc, Alkermes, Inc., Elan Corporation, plc ("Elan") and certain of their respective subsidiaries entered into the Business Combination Agreement and Plan of Merger (the "Business Combination Agreement") pursuant to which Alkermes, Inc. and Elan Drug Technologies ("EDT"), a business unit of Elan, agreed to combine their businesses under the Alkermes plc in a cash and share transaction (the "Business Combination"). On May 4, 2011, Alkermes plc was incorporated by Elan in connection with the negotiation and execution of the Business Combination Agreement solely to effect the Business Combination. Following the execution of the Business Combination Agreement, Elan contributed the assets and legal entities that comprised the EDT business to Alkermes plc through a combination of asset transfers, share transfers and other inter-company transactions, following which the EDT business was contained in several subsidiaries under Alkermes plc.

        On September 16, 2011, the business of Alkermes, Inc. and EDT were combined under Alkermes plc. As part of the Business Combination, a wholly owned subsidiary of Alkermes plc merged with and into Alkermes, Inc., with Alkermes, Inc. surviving as a wholly owned subsidiary of Alkermes plc. At the effective time of the Business Combination, (i) each share of Alkermes, Inc. common stock then issued and outstanding and all associated rights were canceled and automatically converted into and became the right to receive one ordinary share of Alkermes plc and (ii) all issued and outstanding options and stock awards to purchase Alkermes, Inc. common stock granted under any equity compensation plan were converted into options and stock awards to purchase on substantially the same terms and conditions the same number of Alkermes plc ordinary shares at the same exercise price. Alkermes, Inc. was treated as the accounting acquirer under accounting principles generally accepted in the United States ("U.S. GAAP").

        Upon the closing of the Business Combination on September 16, 2011, (i) Dr. Alexander Rich and Michael A. Wall resigned as directors of Alkermes, Inc.; (ii) the board of directors of Alkermes plc was set at eight and each of Geraldine A. Henwood, Floyd E. Bloom, David W. Anstice, Robert A. Breyer, Wendy L. Dixon, Paul J. Mitchell, Richard F. Pops and Mark B. Skaletsky, all of whom were directors of Alkermes, Inc. immediately prior to Business Combination, were appointed as directors of Alkermes plc; (iii) Richard F. Pops and James M. Frates who, immediately prior to the Business Combination, served as the principal executive officer and principal financial officer, respectively, of Alkermes, Inc. were appointed to serve as the principal executive officer and principal financial officer, respectively, of Alkermes plc, and (iv) the following persons were appointed to serve as Alkermes plc executive officers for purposes of the Securities Exchange Act of 1934, as amended (the "Exchange Act"): Richard F. Pops; Shane Cooke; James M. Frates; Michael J. Landine; Kathryn L. Biberstein; Elliot W. Ehrich, M.D.; Gordon G. Pugh; and James L. Botkin. The Company entered into employment agreements with Mr. Cooke and Mr. Botkin, effective upon the closing of the Business Combination. The employment agreements of the other executive officers were not amended in any manner. The Company did not adopt the poison pill that was in place at Alkermes, Inc.

        On February 29, 2012, Mark Stejbach joined Alkermes plc as our Chief Commercial Officer and was also appointed as an executive officer.

        Use of the terms such as "us," "we," "our" "Alkermes" or the "Company" in this proxy statement is meant to refer to Alkermes plc and its subsidiaries, except when the context makes clear that the time period being referenced is prior to September 16, 2011, the closing date of the Business Combination, in which case such terms shall refer to Alkermes, Inc., which, prior to September 16, 2011, was an independent biotechnology company incorporated in the Commonwealth of Pennsylvania and traded on the NASDAQ Global Select Market ("Nasdaq") under the symbol "ALKS." For purposes of this proxy statement, the presentation of full fiscal year information for the Company will consist of information with respect to Alkermes plc for the period from September 17, 2011 through March 31, 2012 and information with respect to Alkermes, Inc., the predecessor company to Alkermes plc from a U.S. GAAP financial reporting perspective, for the period from April 1, 2011 through September 16, 2011. We believe this will provide the most relevant full fiscal year disclosure for Alkermes plc.


 QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why am I receiving these materials?

        The board of directors of Alkermes (the "Board") is soliciting your proxy to vote at the Annual General Meeting of Shareholders (the "Meeting") to be held on August 1, 2012 at 12:30 p.m., local time, at the Company's offices at Connaught House, 1 Burlington Road, Dublin 4, Ireland, and at any postponement or adjournment of the Meeting. You are invited to attend the Meeting to vote on the proposals described in this proxy statement. However, you do not need to attend the meeting to vote your shares. Instead, you may simply complete, sign and return the enclosed proxy card, or follow the instructions below to submit your proxy over the telephone or over the Internet. The Company intends to mail this proxy statement and accompanying proxy card on or about June 22, 2012 to all shareholders of record entitled to vote at the Meeting.

Who can vote at the Meeting?

        Only shareholders who are registered as shareholders as of the close of trading on Nasdaq on June 15, 2012 (the "Record Date") will be entitled to notice of and to vote at the Meeting. On the Record Date, there were 130,703,377 ordinary shares issued and outstanding and entitled to be voted.

Shareholder of Record: Shares Registered in Your Name

        If, as of the Record Date, your ordinary shares were registered directly in your name with the Company's transfer agent, Computershare Trust Company, N.A., then you are a shareholder of record. As a shareholder of record, you may vote in person at the Meeting or vote by proxy. Whether or not you plan to attend the Meeting, we urge you to fill out and return the enclosed proxy card or vote by proxy over the telephone or on the Internet as instructed below to ensure your vote is counted.

Beneficial Owner: Shares Registered in the Name of a Broker or Bank

        If, as of the Record Date, your ordinary shares were not held directly in your name, but rather in an account at a brokerage firm, bank, dealer, or other similar organization, then you are the beneficial owner of shares held in "street name" and these proxy materials are being forwarded to you by that organization. The organization holding your account is considered to be the shareholder of record for purposes of voting at the Meeting. As a beneficial owner, you have the right to direct your broker or other agent regarding how to vote the shares in your account. You are also invited to attend the Meeting. However, since you are not the shareholder of record, you may not vote your shares in person at the Meeting unless you request and obtain a valid proxy from your broker or other agent.

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How do I vote?

        You may vote "For" or "Against" or abstain from voting. The procedures for voting are fairly simple:

Shareholder of Record: Shares Registered in Your Name

        If you are a shareholder of record on the Record Date, you may vote in person at the Meeting, vote by proxy using the enclosed proxy card, vote by proxy over the telephone, or vote by proxy over the Internet. Whether or not you plan to attend the Meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the Meeting and vote in person even if you have already voted by proxy.

        By Internet.    Access the website of our tabulator, Computershare, at: http://www.envisionreports.com/alks, using the voter control number that we have printed on the enclosed proxy card. Your shares will be voted in accordance with your instructions. You must specify how you want your shares voted or your Internet vote cannot be completed and you will receive an error message. The cutoff time for voting by Internet is 11:59 p.m. (EST) on July 31, 2012.

        By Telephone.    Call 1-800-652-VOTE (1-800-652-8683) toll-free from the U.S. and Canada, and follow the instructions on the enclosed proxy card. Your shares will be voted in accordance with your instructions. You must specify how you want your shares voted or your telephone vote cannot be completed. The cutoff time for voting by telephone is 11:59 p.m. (EST) on July 31, 2012.

        By Mail.    Complete and mail the enclosed proxy card in the enclosed postage prepaid envelope to Computershare. Your proxy will be voted in accordance with your instructions. If you sign and return the enclosed proxy but do not specify how you want your shares voted, they will be voted FOR each proposal and according to the best judgment of the proxy holder upon any other business that may properly be brought before the Meeting and at all adjournments and postponements thereof.

        In Person at the Meeting.    If you attend the Meeting, you may deliver your completed proxy card in person or you may vote by completing a ballot, which will be available at the Meeting.

Beneficial Owner: Shares Registered in the Name of Broker or Bank

        If you are a beneficial owner of ordinary shares registered in the name of your broker, bank, or other agent, you should have received a proxy card and voting instructions with these proxy materials from that organization rather than from Alkermes; if you have not, please contact your broker, bank or other agent. Simply complete and mail the proxy card, in accordance with the instructions you receive, to ensure that your vote is counted. Alternatively, you may vote by telephone or over the Internet as instructed by your broker or bank. To vote in person at the Meeting, you must obtain a valid proxy from your broker, bank, or other agent. Follow the instructions from your broker or bank included with these proxy materials, or contact your broker or bank to request a proxy form.

How many votes do I have?

        On each matter to be voted upon, you have one vote for each ordinary share you owned as of the Record Date.

What if I return a proxy card or otherwise vote but do not make specific choices?

        If you return a signed and dated proxy card without making any voting selections, your shares will be voted FOR the election of Geraldine A. Henwood and Floyd E. Bloom as Class 1 directors of the Company; FOR the approval of the amendment to the Alkermes plc 2011 Stock option and Incentive Plan; FOR the advisory vote approving the compensation of our named executive officers; FOR approval of the one-year option as the frequency of the advisory vote on executive compensation; FOR authorization to hold our 2013 Annual General Meeting of Shareholders at a location outside of

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Ireland; FOR appointment of PricewaterhouseCoopers as our independent auditor and authorization for the Audit and Risk Committee of the Board to set auditor remuneration. If any other matter is properly presented at the Meeting, your proxy holder (one of the individuals named on your proxy card) will vote your shares using his or her best judgment.

Who is paying for this proxy solicitation?

        We will pay for the entire cost of soliciting proxies. In addition to these mailed proxy materials, our directors, employees and third party proxy solicitors may also solicit proxies in person, by telephone, or by other means of communication. Directors and employees will not be paid any additional compensation for soliciting proxies. We may also reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one set of proxy materials?

        If you receive more than one set of proxy materials, your ordinary shares are registered in more than one name or are registered in different accounts. Please complete, sign and return each proxy card to ensure that all of your shares are voted.

What is the quorum requirement?

        A quorum of shareholders is necessary to hold a valid Meeting. A quorum will be present if at least one or more shareholders holding not less than a majority of the issued and outstanding shares entitled to vote are present at the Meeting or represented by proxy. On the Record Date, there were 130,703,377 ordinary shares issued and outstanding and entitled to vote. Thus, the holders of 65,351,690 ordinary shares must be present in person or represented by proxy at the Meeting to have a quorum.

        Your shares will be counted towards the quorum only if you submit a valid proxy (or one is submitted on your behalf by your broker, bank or other nominee) or if you vote in person at the Meeting. Abstentions and broker non-votes will be counted towards the quorum requirement. If there is no quorum, within one hour of the time appointed for the Meeting, the Meeting shall stand adjourned to August 8, 2012 at 12:30 p.m. local time at the offices of the Company located at Connaught House, 1 Burlington Road, Dublin 4, Ireland, or such other time or place as the Board may decide.

What vote is required to approve each proposal and how are votes counted?

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How will voting on any other business be conducted?

        The Board knows of no other matters that will be presented for consideration at the Meeting. If any other matters are properly brought before the Meeting, the persons named as your proxy in the accompanying proxy are entitled to vote on those matters in accordance with their best judgment.

How are votes counted?

        Votes will be counted by the inspector of election appointed for the Meeting. Abstentions will be counted as present for purposes of determining the presence of a quorum for purposes of the proposals, but will not be counted as votes cast. Broker non-votes will be counted as present for purposes of determining the presence of a quorum for purposes of the proposals, but will not be voted. Since the approval of all of the proposals is based on the votes properly cast at the Annual General Meeting of Shareholders, abstentions and broker non-votes will not have any effect on the outcome of voting on these proposals.

What are "broker non-votes"?

        Broker non-votes occur when a nominee, such as a broker or bank, holding shares for a beneficial owner does not vote on a particular proposal because the nominee does not have discretionary voting power with respect to that proposal and has not received instructions with respect to that proposal from the beneficial owner. If you do not give instructions to your broker, your broker can vote your shares with respect to "discretionary" items, but not with respect to "non-discretionary" items. Discretionary items are proposals considered routine under the rules of Nasdaq on which your broker may vote shares held in street name in the absence of your voting instructions. We believe that proposal 6 (appointment of PricewaterhouseCoopers as our independent auditor and authorization for the Audit and Risk Committee of the Board to set auditor remuneration) will be considered routine, or discretionary. However, we note that proposals 1 (election of directors), 2 (approval of an amendment to the 2011 Stock Option and Incentive Plan), 3 (the non-binding advisory vote on executive

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compensation), 4 (the non-binding advisory vote on the frequency of the advisory vote on executive compensation) and 5 (authorization to hold the 2013 Annual General Meeting of Shareholders of the Company at a location outside of Ireland) are considered non-routine, non-discretionary items for such purposes. Accordingly, if you own ordinary shares through a nominee, such as a broker or bank, please be sure to instruct your nominee how to vote to ensure that your vote is counted.

Can I change my vote after submitting my proxy?

        Yes. You may revoke your proxy at any time before it is exercised at the Meeting by taking any of the following actions:

        Please note that if your ordinary shares are held of record by a broker or other nominee, you must contact the broker or other nominee to revoke your proxy. If you wish to vote at the Meeting, you must bring to the Meeting a copy of your brokerage account statement or a letter from such broker or other nominee confirming your beneficial ownership of the shares as of the Record Date.

How can I find out the results of the voting at the Meeting?

        Preliminary voting results will be announced at the Meeting. Final voting results will be published in a current report on Form 8-K that we expect to file within four business days of the Meeting. If final voting results are not available to us in time to file a current report on Form 8-K within four business days after the Meeting, we intend to file a current report on Form 8-K to publish preliminary results and, within four business days after the final results are known to us, to file an additional current report on Form 8-K to publish the final results. You will be able to find a copy of this Form 8-K on the Internet through the electronic data system of the U.S. Securities and Exchange Commission ("SEC") called EDGAR at www.sec.gov or through the "Investors" section of our website, www.alkermes.com.

When are shareholder proposals due for next year's Annual General Meeting?

        In accordance with the rules established by the SEC, as well as under the provisions of our Articles of Association, any shareholder proposal submitted pursuant to Rule 14a-8 under the Exchange Act intended for inclusion in the Proxy Statement for next year's Annual General Meeting must be received by us no earlier than January 21, 2013 and no later than March 22, 2013. Such proposals should be sent to our Secretary at Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland. To be included in the Proxy Statement, the proposal must comply with the requirements as to form and substance established by the SEC and our Articles of Association and must be a proper subject for shareholder action under Irish law.

What proxy materials are available on the internet?

        The Notice of the Annual General Meeting, proxy statement, and our Irish Statutory Accounts and Annual Report for the fiscal year ended March 31, 2012 are available at www.edocumentview.com/alks.

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 PROPOSAL 1

ELECTION OF DIRECTORS

(Ordinary resolution)

        Our Board, upon the recommendation of the Nominating and Corporate Governance Committee, has nominated Floyd E. Bloom and Geraldine A. Henwood for election as Class 1 directors to serve a three-year term expiring at the Company's Annual General Meeting of Shareholders in 2015 and until their respective successors are elected and shall qualify, unless they resign or are removed. As described in detail below, our nominees have considerable professional and business expertise. The recommendation of our Board is based on its carefully considered judgment that the experience, qualifications, attributes and skills of our nominees qualify them to serve on our Board.

        The persons named in the accompanying proxy intend to vote for the election of Floyd E. Bloom and Geraldine A. Henwood as Class 1 directors to serve a three-year term expiring at the Company's Annual General Meeting of Shareholders in 2015 and until their respective successors are elected and shall qualify, unless authority to vote for one or more of such nominees is specifically withheld in the proxy. The Board is informed that both of the nominees are willing to serve as directors, but if either of them should decline to serve or become unavailable for election at the Annual General Meeting of Shareholders, an event which the Board does not anticipate, the persons named in the proxy will vote for such nominee or nominees as may be designated by the Board, unless the Board reduces the number of directors accordingly.

        The nominees for Class 1 directors receiving a majority of the votes cast by shareholders entitled to vote thereon will be elected to serve on the Board. Abstentions will be counted as present for purposes of determining the presence of a quorum for purposes of this proposal, but will not be counted as votes cast. Broker non-votes (shares held by a broker or nominee as to which the broker or nominee does not have the authority to vote on a particular matter) will be counted as present for purposes of determining the presence of a quorum for purposes of this proposal but will not be voted. Accordingly, while abstentions and broker non-votes will count towards establishing a quorum, neither abstentions nor broker non-votes will affect the outcome of the vote on this proposal.

        If, at any annual general meeting of shareholders, the number of directors is reduced below the minimum prescribed by the articles of association due to the failure of any director nominee to receive a majority of the votes cast then, in those circumstances, the nominee or nominees who receive the highest number of votes in favor of election will be elected in order to maintain such prescribed minimum number of directors. Each director will remain a director (subject to the provisions of the Companies Acts and our Articles) only until the conclusion of the next annual general meeting of shareholders unless he or she is reelected.

        The Board unanimously recommends that you vote FOR the election of Floyd E. Bloom and Geraldine A. Henwood to our Board.

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 DIRECTORS AND EXECUTIVE OFFICERS

Our Board Structure

        Our Board consists of three classes of directors with each director serving a staggered three-year term as follows:

Class 1 Directors
Term Expires at this
Annual General Meeting
of Shareholders 		  Class 2 Directors
Term Expires at 2013
Annual General Meeting
of Shareholders 		  Class 3 Directors
Term Expires at 2014
Annual General Meeting
of Shareholders
Geraldine A. Henwood   David W. Anstice   Paul J. Mitchell
Floyd E. Bloom   Robert A. Breyer   Richard F. Pops*
    Wendy L. Dixon   Mark B. Skaletsky
*
Chairman of the Board

Directors and Executive Officers

        The following table sets forth our directors and executive officers, their ages and the position currently held by each such person as of June 15, 2012. The following biographical descriptions set forth information regarding each director and executive officer, including business experience and, for directors, the experiences, qualifications, attributes or skills that caused the Nominating and Corporate Governance Committee and the board of directors, or Board, to determine that the person should serve as our director. Information about the number of our ordinary shares beneficially owned by each director and executive officer, directly and indirectly, appears elsewhere in this proxy statement under the heading "Ownership of the Company's Ordinary Shares." Unless otherwise indicated, each of our executive officers is employed through our U.S. subsidiary, Alkermes, Inc.

Name
  Age   Position

Ms. Kathryn L. Biberstein

     53   Senior Vice President, General Counsel and Secretary, and Chief Compliance Officer

Mr. James L. Botkin

     63   Senior Vice President, Operations

Mr. Shane Cooke

     50   President

Dr. Elliot W. Ehrich

     53   Senior Vice President, Research and Development, and Chief Medical Officer

Mr. James M. Frates

     45   Senior Vice President and Chief Financial Officer

Mr. Michael J. Landine

     58   Senior Vice President, Corporate Development

Mr. Gordon G. Pugh

     54   Senior Vice President, Chief Operating Officer and Chief Risk Officer

Mr. Mark Stejbach

     49   Senior Vice President, Chief Commercial Officer

Mr. Richard F. Pops

     50   Director, Chairman of the Board and Chief Executive Officer

Mr. David W. Anstice(3)

     63   Director

Dr. Floyd E. Bloom(1)

     75   Director

Mr. Robert A. Breyer(2)

     68   Director

Dr. Wendy L. Dixon(2)

     56   Director

Ms. Geraldine A. Henwood(2*)

     59   Director

Mr. Paul J. Mitchell(1*)(3)

     59   Director

Mr. Mark B. Skaletsky(1)(3*)

     63   Director
(1)
Member, Audit and Risk Committee

(2)
Member, Nominating and Corporate Governance Committee

(3)
Member, Compensation Committee

*
Committee Chairperson

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Biographical Information

        Ms. Biberstein is our Senior Vice President, General Counsel and Secretary, and Chief Compliance Officer. Until September 16, 2011, she was Senior Vice President, Government Relations and Public Policy, General Counsel and Secretary and Chief Compliance Officer of Alkermes. From March 2003 to May 2007, Ms. Biberstein served as Vice President and General Counsel of Alkermes. She was Of Counsel at Crowell & Moring LLC from February 2002 to February 2003 and performed legal consulting services for various clients from March 2000 to February 2002. She was also employed by Serono S.A., a biotechnology company, as General Counsel from 1993 to March 2000, where she was a member of the Executive Committee.

        Mr. Botkin is our Senior Vice President, Operations. He is employed by Alkermes Gainesville LLC. Until September 16, 2011, Mr. Botkin was Senior Vice President, Head of Operations of EDT, having been appointed in June 2007. He was formerly Vice President and General Manager of Elan's operations in Gainesville, Georgia from October 2001 to June 2007, President of Sharp Corporation, a private pharmaceutical packaging company, from January 1996 to June 2001, as well as Vice President, United States Production Operations of Sandoz Pharmaceutical Corporation from January 1993 to December 1995. Mr. Botkin has over 40 years of experience in pharmaceutical industry operations. Mr. Botkin is a former Director of FirsTier Bank, Lincoln General Hospital and the Healthcare Compliance Packaging Council.

        Mr. Cooke is our President. He is employed by Alkermes Pharma Ireland Limited, an Irish subsidiary of the company. From May 2005 to September 16, 2011, Mr. Cooke served as a Director of Elan. From May 2007 to September 16, 2011, Mr. Cooke was Executive Vice President of Elan and Head of EDT and had been Chief Financial Officer of Elan from July 2001, when he joined Elan, until May 2011. Prior to joining Elan, Mr. Cooke was Chief Executive of Pembroke Capital Limited, an aviation leasing company, and prior to that held a number of senior positions in finance in the banking and aviation industries. He is a chartered accountant.

        Dr. Ehrich is our Senior Vice President, Research and Development, and Chief Medical Officer. Until September 16, 2011, Dr. Ehrich served Senior Vice President of Research and Development and Chief Medical Officer at Alkermes. From May 2007 to September 2011, Dr. Ehrich also led the Research and Development, Clinical Sciences and Drug Safety functions at Alkermes. Prior to assuming this position in May 2007, Dr. Ehrich served as Vice President, Science Development and Chief Medical Officer of Alkermes. Prior to joining Alkermes in 2000, Dr. Ehrich spent seven years at Merck & Co., Inc. ("Merck"), a publicly traded pharmaceutical company, overseeing the clinical development and registration of novel pharmaceuticals. Dr. Ehrich is a Fellow of the American College of Rheumatology and has had numerous publications in peer-reviewed journals. Dr. Ehrich worked as a research associate at the European Molecular Biology Laboratory in Heidelberg, Germany before attending medical school. Dr. Ehrich is also a member of the scientific advisory board for Aileron Therapeutics, a privately held biopharmaceutical company.

        Mr. Frates is our Senior Vice President and Chief Financial Officer. Until September 16, 2011, Mr. Frates was Senior Vice President, Chief Financial Officer and Treasurer of Alkermes. From June 1998 to May 2007, Mr. Frates served as Vice President, Chief Financial Officer and Treasurer of Alkermes. From June 1996 to June 1998, he was employed at Robertson, Stephens & Company, most recently as a Vice President in Investment Banking. Prior to that time he was employed at Morgan Stanley & Co. Mr. Frates served on the Board of Directors of GPC Biotech AG, a biotechnology company, from June 2004 to 2009, and was a national director of the Association of Bioscience Financial Officers from 2004 to 2009. Mr. Frates is also a Trustee of St. Paul's School.

        Mr. Landine is our Senior Vice President, Corporate Development. Until September 16, 2011, Mr. Landine was Senior Vice President, Corporate Development of Alkermes. From March 1999 until May 2007, Mr. Landine served as Vice President, Corporate Development of Alkermes. From March

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1988 until June 1998, he was Chief Financial Officer and Treasurer of Alkermes. Mr. Landine is a member of the board of directors of Kopin Corporation, a publicly traded manufacturer of components for electronic products, and ECI Biotech, a privately held protein sensor company. He also served as a director of GTC Biotherapeutics, Inc., a publicly traded biotechnology company, from 2005 to 2010. Mr. Landine is a Certified Public Accountant.

        Mr. Pugh is our Senior Vice President, Chief Operating Officer and Chief Risk Officer. Until September 16, 2011, Mr. Pugh served as Senior Vice President, Chief Operating Officer and Chief Risk Officer of Alkermes. In that role, he was responsible for the overall leadership of the operations departments of Alkermes. Additionally, he oversaw site management in Waltham, Massachusetts, and Wilmington, Ohio. Prior to assuming the Senior Vice President and Chief Operating Officer positions in May 2007 and the Chief Risk Officer position in July 2010, Mr. Pugh served as Vice President of Operations at Alkermes. Mr. Pugh has over 30 years of operations and manufacturing experience. For the eight-year period prior to joining Alkermes, Mr. Pugh worked at Lonza Biologics, Inc., a publicly traded life sciences company, as the Vice President of manufacturing operations in the United States and Europe. Mr. Pugh has served on the board of directors of KC Bio LLC, a privately held company, since 2000.

        Mr. Stejbach is our Senior Vice President, Chief Commercial Officer. Prior to assuming this position, Mr. Stejbach served at Tengion, Inc. from 2008 to 2012, most recently as its Chief Commercial Officer. He previously held senior positions at Merck & Co. and Biogen Idec Inc. and has 25 years of experience in biotech and pharmaceutical marketing, sales, managed care, and finance. Mr. Stejbach served on the charitable board of the Commonwealth National Fund from 2003 through 2011 and has served on the Advisory Board of the Center for Value-Based Insurance Design since 2009.

        Mr. Pops is our Chairman of the Board of Directors and Chief Executive Officer. Until September 16, 2011, Mr. Pops was Chief Executive Officer, President and Chairman of the Board of Alkermes. Mr. Pops served as Chief Executive Officer of Alkermes from February 1991 to April 2007 and as Chief Executive Officer and President since September 2009. He was a director of Alkermes from February 1991 to September 2011 and was Chairman of the Board of Alkermes since April 2007. Mr. Pops serves on the board of directors of Neurocrine Biosciences, Inc., a publicly traded biopharmaceutical company, Acceleron Pharma, Inc. and Epizyme Inc., both of which are privately held biotechnology companies, Biotechnology Industry Organization, and PhRMA. He has previously served on the board of directors of two other publicly traded biopharmaceutical companies, Sirtris Pharmaceuticals from 2004 to 2008, and CombinatoRx, Incorporated from 2001 to 2009. Mr. Pops also served on the board of directors of Reliant Pharmaceuticals, a privately held pharmaceutical company purchased by GlaxoSmithKline in 2007, and on the advisory board of Polaris Venture Partners. He is also a member of the Harvard Medical School Board of Fellows. Mr. Pops' qualifications for our Board include his leadership experience, business judgment and industry knowledge. As a senior executive of Alkermes for almost 22 years, he provides in-depth knowledge of our company derived from leading our day to day operations. His ongoing involvement as a board member of Biotechnology Industry Organization and PhRMA brings to the organization extensive knowledge of the current state of the pharmaceutical industry.

        Mr. Anstice has served as a director of Alkermes plc since September 16, 2011. From October 2008 to September 16, 2011, he served on Alkermes' board of directors. From 2006 to 2008, he served as Executive Vice President of Merck, with responsibility for enterprise strategy and implementation. During two separate parts of this period he was acting President, Global Human Health and President of Merck's business in Japan. From 2003 to 2006, Mr. Anstice served as President of Merck, with responsibility for Merck's Asia Pacific businesses. In his 34 years with Merck, he held a variety of positions with their worldwide ventures, including President, U.S. Human Health; President Human Health, the Americas; President, U.S./Canada; and President, Human Health, Europe. Mr. Anstice is also Chairman and President of the board for the University of Sydney USA Foundation, a member of

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the board of the U.S. Studies Centre based at the University of Sydney, Australia and the Board of USA Foundation of the University of the Valley of Guatemala, a member of the U.S. Advisory Council for the American Australian Association in New York, a director of CSL Limited, a global specialty biopharmaceutical company, and an Adjunct Professor at the University of Sydney Business School. Mr. Anstice's lengthy service with Merck & Co., in combination with the breadth of his responsibilities while at Merck, provides us with experience in and knowledge about the pharmaceutical industry. Mr. Anstice's prior leadership positions in industry organizations, including as a board member of the Biotechnology Industry Organization for approximately ten years, augment his pharmaceutical management and organizational expertise and industry knowledge. Mr. Anstice also has expertise in the areas of strategic planning, risk management and corporate governance.

        Dr. Bloom has served as a director of Alkermes plc since September 16, 2011. Dr. Bloom is a founder of Alkermes, Inc. and from 1987 to September 16, 2011 served on Alkermes' board of directors. Dr. Bloom has been active in neuropharmacology for more than 35 years, holding positions at Yale University, the National Institute of Mental Health and The Salk Institute. From 1983 to February 2005, Dr. Bloom was the Chairman of the Neuropharmacology Department at The Scripps Research Institute and Professor Emeritus. Dr. Bloom served as Editor-in-Chief of Science from 1995 to May 2000. He is a member of the National Academy of Science, the Institute of Medicine, the Royal Swedish Academy of Science, Veteran's Administration—Gulf War Veterans Illness Research and the Washington University Board of Trustees. Dr. Bloom is a director of LZ Therapeutics, a privately held biopharmaceutical company. Dr. Bloom also serves on the Scientific Advisory Boards of aTyr Pharma, Riverest and AgeneBio, Inc., all privately held pharmaceutical companies. Dr. Bloom served as a member of the board of directors of Elan from 2007 to 2009 and serves as an advisor to its Science and Technology Committee. Dr. Bloom is a distinguished scientist and long-standing member of various scientific societies, including the National Academy of Sciences. His scientific knowledge makes him a resource to our research and development and commercial teams and a reference point for other directors. Dr. Bloom's service on other publicly traded company boards provides experience relevant to good corporate governance practices. As a founder of Alkermes, Inc., Dr. Bloom brings a historical perspective to the Board.

        Mr. Breyer has served as a director of Alkermes plc since September 16, 2011. From July 1994 to September 16, 2011, Mr. Breyer served on Alkermes' board of directors. He served as the President of Alkermes from July 1994 until his retirement in December 2001 and Chief Operating Officer from July 1994 to February 2001. Prior to that time, Mr. Breyer was an executive and held various positions in the global pharmaceutical and medical device industries, including in the United States, the Netherlands, Belgium and Italy. Mr. Breyer also served on the board of directors of Lentigen, Inc., a privately held, diversified biology company from 2007 to 2009. Mr. Breyer's experience as an executive in the pharmaceutical and medical device industries provides management and operational skills to our board of directors. Mr. Breyer has experience with managing the overall financial performance of pharmaceutical and medical device units and in pharmaceutical manufacturing and sales and marketing operations. As a former executive at Alkermes, Inc., Mr. Breyer also has first-hand knowledge of our technology, manufacturing operations, research and development and management team.

        Dr. Dixon has served as a director of Alkermes plc since September 16, 2011. From January 2011 to September 16, 2011, Dr. Dixon served on Alkermes' board of directors. She has extensive experience in the pharmaceutical and biotechnology industries, combining a technical background with experience in drug development, regulatory affairs and marketing. She directed the launches and growth of more than 20 pharmaceutical products. From 2001 to 2009 she was Chief Marketing Officer and President, Global Marketing for Bristol-Myers Squibb where she served on the Executive Committee. From 1996 to 2001 she was Senior Vice President, Marketing at Merck and prior to that she held executive management positions at West Pharmaceuticals, Osteotech, and Centocor and various positions at SmithKline and French (now GlaxoSmithKline) in marketing, regulatory affairs, project management

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and as a biochemist. Dr. Dixon is on the board of directors of Furiex Pharmaceuticals, Orexigen Therapeutics, Ardea Biosciences and Incyte Corporation, all publicly traded biotechnology or pharmaceutical companies, and was formerly on the board of Dentsply International. She is also a Senior Advisor to The Monitor Group, a worldwide consulting firm. Dr. Dixon brings a depth of experience in the marketing of pharmaceutical products across a broad variety of disease states and on a global basis to our board. Dr. Dixon has a strong technical background and direct experience in product development and regulatory affairs, and has successfully built and grown commercial organizations in the United States and Europe, each of which provide valuable insight to our board regarding the development and commercialization of pharmaceutical products. Dr. Dixon's additional qualifications include her deep industry knowledge and her reputation as a strategic thinker with a focus on execution, as well as the ability to provide direction regarding improvements to the interface between research and development and marketing.

        Ms. Henwood has served as a director of Alkermes plc since September 16, 2011. From April 2003 to September 16, 2011, Ms. Henwood served on Alkermes' board of directors. She is currently the Chief Executive Officer/President and director of both Recro Pharma, a privately held specialty pharmaceutical company, and interim chief executive officer and board member of Garnet BioTherapeutics, Inc., a privately held clinical stage cell therapy company, and is a consultant with Malvern Consulting Group and SCP Partners. She is the co-founder of Auxilium Pharmaceuticals, Inc. and served as its President, Chief Executive Officer and director from 1999 to 2006. Prior to founding Auxilium, Ms. Henwood founded, in 1985, a contract research organization (CRO), IBAH, Inc. Prior to founding IBAH, Ms. Henwood was employed by SmithKline Beecham in various capacities including senior medical and regulatory positions. Ms. Henwood is a member of the board of directors of MAP Pharmaceuticals, Inc., a publicly traded pharmaceutical company and LZ Therapeutics, a privately held biopharmaceutical company, and previously served as a director of ImmunoScience, Inc., a privately held vaccine development company. She is also a trustee of LaSalle Academy and Neumann University. Ms. Henwood brings expertise in clinical development and regulatory approval processes to our Board. Ms. Henwood's experience at large and small pharmaceutical and biotechnology companies provides insight into drug development, both as conducted by us or in partnership with large pharmaceutical companies. Ms. Henwood's additional qualifications include her industry knowledge and the management and operational experience she acquired as the Chief Executive Officer of several pharmaceutical and biotechnology companies. Her service on various life science boards brings relevant corporate governance experience to our Board.

        Mr. Mitchell has served as a director of Alkermes plc since September 16, 2011. From April 2003 to September 16, 2011, Mr. Mitchell served on Alkermes' board of directors. He served as the Chief Financial Officer and Treasurer of Kenet, Inc. from April 2002 until January 2009. Prior to joining Kenet, Mr. Mitchell was the Chief Financial Officer and Treasurer of Kopin Corporation from April 1985 through September 1998. From September 1998 through June 2001, Mr. Mitchell served in a consulting role at Kopin as Director of Strategic Planning. Prior to joining Kopin, Mr. Mitchell worked for the international accounting firm of Touche Ross & Co. from 1975 to 1984. Mr. Mitchell is also President of Mitchell Financial Group and a member of the board of directors of several private companies. Mr. Mitchell is a Certified Public Accountant. Mr. Mitchell's background as the Chief Financial Officer of several companies, including a publicly traded company, and as a certified public accountant provides expertise to our Board in the areas of financial reporting, treasury, financing issues, executive compensation and compliance with securities obligations. His business judgment is relied upon by our Board when contemplating a variety of organizational and strategic issues.

        Mr. Skaletsky has served as a director and as the Lead Independent Director of Alkermes plc since September 16, 2011. From June 2004 to September 16, 2011, Mr. Skaletsky was a director of Alkermes and, since March 2010, had served as its Lead Independent Director. He is currently the Chief Executive Officer and President of Fenway Pharmaceuticals. From 2001 to 2007, Mr. Skaletsky

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was the Chairman, Chief Executive Officer and President of Trine Pharmaceuticals, Inc. Prior to that, Mr. Skaletsky was the Chairman and Chief Executive Officer of The Althexis Company from 2000 to 2001 and President and Chief Executive Officer of GelTex Pharmaceuticals, Inc. from 1993 to 2000, which was acquired by Genzyme in December 2000. Mr. Skaletsky held the position of Chairman and Chief Executive Officer of Enzytech, Inc., from 1988 to 1993, and he was President and Chief Operating Officer of Biogen, Inc., from 1981 to 1988. Mr. Skaletsky was among the founders of the Industrial Biotechnology Association, a predecessor to BIO, and is a former chairman of BIO. He serves on the board of directors of ImmunoGen, Inc. and Targacept, Inc. He served on the board of directors of AMAG Pharmaceuticals from 2005 to 2009. In addition, Mr. Skaletsky is a member of the Board of Trustees of Bentley University. Mr. Skaletsky's qualifications to serve on our Board include his broad industry knowledge as well as the leadership and financial expertise he acquired as an executive officer of several pharmaceutical and biotechnology companies. As the past and present Chief Executive Officer of several biotechnology companies, as well as director of several other life science companies, he brings to our board knowledge and expertise on corporate governance, executive compensation, corporate alliances and financial management of publicly traded companies.

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 CORPORATE GOVERNANCE AND BOARD MATTERS

Board Composition

        Our board of directors is comprised of eight members. Our board of directors has determined that each director serving on our board of directors, with the exception of Richard F. Pops, is an independent director as defined by the Nasdaq rules. The composition and functioning of our board of directors and each of our committees complies with all applicable requirements of Nasdaq and the rules and regulations of the Securities and Exchange Commission. There are no family relationships among any of our directors or executive officers.

        In accordance with our articles of association, our board of directors is divided into three classes with staggered three-year terms. At each Annual General Meeting of Shareholders, the successors to directors whose terms then expire will be elected to serve three-year terms. Our directors are divided among the three classes as follows:

        If the number of directors is changed, any increase or decrease shall be apportioned among the classes so as to maintain the number of directors in each class as nearly equal as possible. The division of our board of directors into three classes with staggered three-year terms may delay or prevent a change of our management or a change in control.

Independence of Members of the Board of Directors

        The Company defines an "independent" director in accordance with the applicable provisions of the Exchange Act, the rules promulgated thereunder and the applicable rules of Nasdaq. Because it is not possible to anticipate or explicitly provide for all potential situations that may affect independence, the Board periodically reviews each director's status as an independent director and whether any independent director has any other relationship with the Company that, in the judgment of the Board, would interfere with the director's exercise of independent judgment in carrying out such director's responsibilities as a director. The Board makes a determination as to whether each director is "independent" under the applicable provisions of the Exchange Act, the rules promulgated thereunder and the applicable rules of Nasdaq at two points in time during the year—after the Annual General Meeting of Shareholders and in conjunction with the preparation and filing of the Company's proxy statement. In fiscal year 2012, this independence assessment was also conducted after the close of the Business Combination. To assist in making its determination, the Board solicits information from each of the Company's directors regarding whether such director, or any family member of his immediate family, had a direct or indirect material interest in any transactions involving the Company, was involved in a debt relationship with the Company or received personal benefits outside the scope of such person's normal compensation.

        The Board has determined that each of David W. Anstice, Floyd E. Bloom, Robert A. Breyer, Wendy L. Dixon, Geraldine A. Henwood, Paul J. Mitchell, and Mark B. Skaletsky are independent within the meaning of the Company's director independence standards and the director independence standards of the Exchange Act and Nasdaq. Furthermore, the Board has determined that each member of each committee of the Board of Directors is independent within the meaning of the director independence standards of the Company, the Exchange Act and Nasdaq.

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Executive Sessions of Independent Directors

        The Board's policy is to hold meetings of the independent directors following each regularly scheduled in-person Board meeting. Independent director sessions do not include any employee directors of the Company. The Board has adopted a Charter of the Lead Independent Director which requires that members of the Board elect a non-management director to serve in a lead capacity if the Chairman of the Board and Chief Executive Officer of the Company are the same person (such person called the "Lead Independent Director"). Mr. Skaletsky has served as our Lead Independent Director since March 2010. The Board annually elects an independent director to serve as the Lead Independent Director.

Board Leadership Structure

        The Board appointed Mr. Pops as Chairman of our Board and as our Chief Executive Officer. In determining that Mr. Pops serve in this combined role, the Board considered Mr. Pops' ability to provide consistent and continuous leadership to both our Board and our Company at a time of changing Company priorities, his ability to coordinate the strategic objectives of both management and the Board, his extensive knowledge of our operations and the industry and markets in which we compete and his ability to promote communication and synchronize activities between our Board and our senior management.

        To facilitate effective independent oversight, the Board adopted a Lead Independent Director role, in which, as previously noted, Mr. Skaletsky currently serves. The Board believes that this structure provides an efficient and effective leadership model for the Company and we believe that this Board leadership structure is the most appropriate structure for the Company as of the date of this proxy statement. The duties of the Lead Independent Director include:

        A current copy of our Charter of the Lead Independent Director is available on the Corporate Governance page of the Investors section of the Company's website, available at http://investor.alkermes.com.

        In addition, the Board has three standing committees, each of which is comprised solely of independent directors and led by an independent chair. These committees are discussed in detail below and under the heading "Board Committees."

Policies Governing Director Nominations

Director Qualifications and Consideration of Diversity

        The Nominating and Corporate Governance Committee is responsible for reviewing with the Board, from time to time, the appropriate qualities, skills and characteristics desired of Board members in the context of the current make-up of the Board. This assessment includes consideration of the

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following minimum qualifications that the Nominating and Corporate Governance Committee believes must be met by all directors:

        Although we do not have a formal diversity policy, we and the Nominating and Corporate Governance Committee endeavor to have a Board representing diverse viewpoints with broad experience in areas important to the operation of our Company such as business, science, medicine, finance/accounting, and education. In this context, the Nominating and Corporate Governance Committee, in addition to the minimum qualifications set forth above, also considers a variety of attributes in selecting nominees to the Board, such as:

        These factors and others are considered useful by the Board, and are reviewed in the context of an assessment of the perceived needs of the Board at a particular point in time.

        Board members are expected to prepare for, attend, and participate in all Board meetings, meetings of Board committees on which they serve and the Company's Annual General Meeting of Shareholders. In addition, directors should stay abreast of the Company's business and markets. The General Counsel and the Chief Financial Officer will be responsible for assuring the orientation of new directors, and for periodically providing materials or briefing sessions for all directors on subjects that would assist them in discharging their duties. Periodically, the Company will provide opportunities for directors to visit Company facilities in order to provide greater understanding of the Company's business and operations. The Board performs an annual self-evaluation. The Board, in coordination with each Board committee, performs an annual performance evaluation of each such committee. The Board, following review by the Nominating and Corporate Governance Committee, determines whether other educational measures are appropriate as part of the annual Board evaluation.

        Each Board member is expected to ensure that other existing and planned future commitments do not materially interfere with the member's service as a director. Board members should not hold more than six directorships (including such member's seat on the Company's Board), excluding for this purpose, not-for-profit organizations, trade organizations and related organizations, unless otherwise agreed to by the Nominating and Corporate Governance Committee. These other commitments will be considered by the Nominating and Corporate Governance Committee and the Board when reviewing Board candidates. Directors are expected to report changes in their primary business or professional association, including retirement, to the Chairman of the Board and the chair of the Nominating and Corporate Governance Committee. The Nominating and Corporate Governance Committee, in consultation with the Chairman of the Board, will consider any effects these changes may have on the effectiveness of the director's contribution to the work of the Board.

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Process for Identifying and Evaluating Director Nominees

        The Board is responsible for selecting its own members to stand for election. The Board delegates the selection and nomination process to the Nominating and Corporate Governance Committee, with the expectation that other members of the Board and management will be requested to take part in the process as appropriate.

        Once candidates have been identified, the Nominating and Corporate Governance Committee confirms that the candidates meet all of the minimum qualifications for director nominees established by the Nominating and Corporate Governance Committee. Based on the results of the evaluation process, the Nominating and Corporate Governance Committee recommends candidates for the Board's approval as director nominees for election to the Board. The Nominating and Corporate Governance Committee also recommends candidates for the Board's appointment to the committees of the Board.

Procedure for Recommendation of Director Nominees by Shareholders

        The Nominating and Corporate Governance Committee will consider director candidates who are recommended by shareholders of the Company. Shareholders, in submitting recommendations to the Nominating and Corporate Governance Committee for director candidates, shall follow the following procedures:

        Such recommendation for nomination must be in writing and include the following:

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        The Secretary of the Company will promptly forward any such nominations to the Nominating and Corporate Governance Committee. Once the Nominating and Corporate Governance Committee receives the nomination of a candidate, the candidate will be evaluated and a recommendation with respect to such candidate will be delivered to the Board. Nominations not made in accordance with the foregoing policy shall be disregarded by the Nominating and Corporate Governance Committee and votes cast for such nominee shall not be counted.

Composition and Responsibilities of the Board of Directors

        The Company's business, property and affairs are managed under the direction of the Board. Members of the Board are kept informed of the Company's business through discussions with the Chief Executive Officer and other officers of the Company, by reviewing materials provided to them, by visiting the Company's offices and by participating in meetings of the Board and its committees and the Annual General Meeting of Shareholders.

Size of the Board

        The Board of Directors currently consists of eight members. The Board periodically reviews the appropriate size of the Board and, in accordance with the Company's Articles of Association, this number may be adjusted from time to time by the Board.

Board Compensation

        It is the general policy of the Board that Board compensation should be a mix of cash and equity based compensation. Full-time employee directors will not be paid for Board membership in addition to their regular employee compensation. Independent directors may not receive consulting, advisory or other compensatory fees from the Company if the receipt of such fees would result in disqualifying the director as an "independent" director in accordance with the applicable provisions of the Exchange Act, the rules promulgated thereunder and the applicable rules of Nasdaq. To the extent practicable or required by applicable rule or regulation, independent directors who are affiliated with the Company's service providers or partners or collaborators will undertake to ensure that their compensation from such providers or partners or collaborators does not include amounts connected to payments by the Company. The Compensation Committee periodically reviews director compensation.

Board's Role in Risk Oversight

        Assessing and managing risk is the responsibility of our management and our Board oversees and reviews various aspects of the Company's risk management efforts. The Board executes its oversight responsibility for Company risk management directly and through its Board committees, as set forth below.

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        In performing their risk oversight functions, each Board Committee has full access to management, as well as the ability to engage outside advisors.

Succession Plan

        The chair of our Compensation Committee and members of our Nominating and Corporate Governance Committee review and discuss succession planning with our Chief Executive Officer. On an annual basis, the chair of our Compensation Committee and Chief Executive Officer review succession planning with the Board of Directors.

Scheduling and Selection of Agenda Items for Board Meetings

        In-person Board meetings are scheduled in advance at least four times a year. Furthermore, additional Board meetings may be called upon appropriate notice at any time to address specific needs of the Company. Each director may propose the inclusion of items on the agenda, request the presence of or a report by any member of the Company's management, or at any Board meeting raise subjects that are not on the agenda for that meeting. The Lead Independent Director approves the Board agenda in advance of the meeting. The Board may also take action from time to time by unanimous written consent.

        The meetings of the Board are typically held at the Company's headquarters in Dublin, Ireland, but occasionally meetings may be held at other locations at the discretion of the Board.

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Board Committees

        The Company currently has three standing committees: Audit and Risk, Compensation, and the Nominating and Corporate Governance Committees. There will, from time to time, be occasions on which the Board may form a new committee or disband a current committee depending upon the circumstances. The Audit and Risk, Compensation and Nominating and Corporate Governance Committees are each composed entirely of independent directors.

        Each Board committee has a written charter, approved by the Board, which describes the committee's general authority and responsibilities. A current copy of each charter is available on the Corporate Governance page of the Investors section of the Company's website, available at http://investor.alkermes.com. Each Board committee undertakes an annual review of its charter and works with the Board to make such revisions as are considered appropriate.

        Each Board committee has the authority to engage outside experts, advisors and counsel to the extent it considers appropriate to assist the Board committee in its work.

Assignment of Committee Members

        The Board is responsible for the appointment of committee members. The Nominating and Corporate Governance Committee recommends candidates to the Board for appointment to the Board committees.

Frequency and Length of Committee Meetings and Committee Agenda

        The chair of each Board committee, in consultation with the Chairman of the Board and appropriate members of management, will determine the frequency and length of the committee meetings and develop the committee's agenda. The agendas and meeting minutes of the Board committees will be shared with the full Board, and other Board members are welcome to attend Board committee meetings, except that non-independent directors are not permitted to attend the executive sessions of any Board committee.

        Each Board committee regularly reports to the Board concerning such committee's activities.

Policies Governing Security Holder Communications with the Board of Directors

        The Board provides to every security holder the ability to communicate with the Board, as a whole, and with individual directors on the Board through an established process for security holder communication (as that term is defined by the rules of the Securities and Exchange Commission) as follows:

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        The Company will forward any such security holder communication to the Chairman of the Board, as a representative of the Board, and/or to the director to whom the communication is addressed on a periodic basis. The Company will forward such communication by certified mail to an address specified by each director and the Chairman of the Board for such purposes or by secure electronic transmission.

Policy Governing Director Attendance at Annual General Meetings of Shareholders

        The Board adopted a policy that all directors and all nominees for election as directors attend the Company's Annual General Meeting of Shareholders in person. The 2012 Annual General Meeting of Shareholders will be the first annual general meeting of Alkermes plc.

Code of Ethics

        The Company has adopted a "code of ethics" (as defined by the regulations promulgated under the Securities Act of 1933, as amended, and the Exchange Act) that applies to all of the Company's directors and employees, including principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. The Company's Code of Business Conduct and Ethics also meets the requirements of a "code of conduct" (as defined by the rules of Nasdaq) and is applicable to all of the Company's officers, directors and employees. A current copy of the Code of Business Conduct and Ethics is available on the Corporate Governance page of the Investors section of the Company's website, available at http://investor.alkermes.com. We intend to disclose any amendments to the code, or any waivers of its requirements, on our website. A copy of the Code of Business Conduct and Ethics may also be obtained, free of charge, from the Company upon request directed to: Alkermes plc, Attention: Investor Relations, Connaught House, 1 Burlington Road, Dublin 4, Ireland.

        Members of the Board of Directors shall act at all times in accordance with the requirements of the Company's Code of Business Conduct and Ethics, which shall be applicable to each director in connection with his or her activities relating to the Company. This obligation shall at all times include, without limitation, adherence to the Company's policies with respect to conflicts of interest, confidentiality, protection of the Company's assets, ethical conduct in business dealings and respect for and compliance with applicable law. Any waiver of the requirements of the Code of Business Conduct and Ethics with respect to any individual director or any executive officer shall be reported to, and be subject to the approval of, the Board of Directors.

        For more corporate governance information, you are invited to access the Corporate Governance page of the Investors section of the Company's website, available at: http://investor.alkermes.com.

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 THE BOARD OF DIRECTORS AND ITS COMMITTEES

        Our Board held eight meetings during the last fiscal year and otherwise acted by unanimous consent. All of the Company's directors attended at least 75% of the aggregate of all meetings held during the prior full fiscal year of the Board and of all committees of which the director was a member. The standing committees of the Board are the Audit and Risk Committee, the Nominating and Corporate Governance Committee and the Compensation Committee.

Audit and Risk Committee

        The Audit and Risk Committee consists of Paul J. Mitchell, Mark B. Skaletsky and Floyd E. Bloom, each of whom is independent as defined by Rule 5605(a)(2) and as required under Rule 5605(c)(2) of the Nasdaq's listing standards, as well as under the applicable requirements of the Exchange Act. Mr. Mitchell serves as chair of the Audit and Risk Committee. In compliance with the Sarbanes-Oxley Act of 2002, the entire Board determined, based on all available facts and circumstances, that Mr. Mitchell and Mr. Skaletsky are both "audit committee financial experts" as defined by the SEC. The Audit and Risk Committee met five times during the last fiscal year.

        The Audit and Risk Committee operates under a written charter adopted by the board of directors, a current copy of which can be found on the Corporate Governance tab of the Investors section of our website, available at: http://investor.alkermes.com. Under the terms of its current charter, the Audit and Risk Committee is responsible for (1) appointing, compensating and retaining our independent auditors, (2) overseeing the work performed by any independent auditors, (3) assisting the board of directors in fulfilling its responsibilities by: (i) reviewing the financial reports we provide to the SEC, our shareholders or to the general public, (ii) reviewing our internal financial and accounting controls and (iii) reviewing all related party transactions, (4) recommending, establishing and monitoring procedures designed to improve the quality and reliability of the disclosure of our financial condition and results of operations, (5) assessing and providing oversight to management relating to the identification and evaluation of major strategic, operational, regulatory, compliance and external risks inherent to our business and (6) establishing procedures designed to facilitate: (i) the receipt, retention and treatment of complaints relating to accounting, internal accounting controls or auditing matters and (ii) the receipt of confidential, anonymous submissions by employees of concerns regarding questionable accounting or auditing matters. The committee will engage advisors as necessary, distribute relevant funding provided by the Company, and serve as the Qualified Legal Compliance Committee (the "QLCC") in accordance with Section 307 of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated by the Securities and Exchange Commission thereunder. Additionally, the Audit and Risk Committee is responsible for approving, in advance, any and all audit and non-audit services to be performed by PricewaterhouseCoopers. All services provided by PricewaterhouseCoopers during fiscal year 2012 were pre-approved by the Audit and Risk Committee.

Nominating and Corporate Governance Committee

        Since September 16, 2011, Geraldine A. Henwood, Robert A. Breyer and Wendy L. Dixon, each of whom is independent as defined in Rule 5605(a)(2) of the Nasdaq listing standards, have served as members of our Nominating and Corporate Governance Committee. Ms. Henwood serves as chair of the Nominating and Corporate Governance Committee. From March 31, 2011 until September 16, 2011, the effective date of the Business Combination, Alexander Rich and Floyd E. Bloom, who were also deemed independent as defined in Rule 5605(a)(2) of the Nasdaq listing standards, served as members of the Nominating and Corporate Governance Committee along with Ms. Henwood. During the last fiscal year, the Nominating and Corporate Governance Committee met three times.

        The Nominating and Corporate Governance Committee operates under a written charter adopted by the board of directors, a current copy of which can be found on the Corporate Governance tab of

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the Investors section of our website, available at: http://investor.alkermes.com. Under the terms of its current charter, the Nominating and Corporate Governance Committee is responsible for (1) identifying individuals qualified to become members of the board and recommending that the board select the director nominees for election, (2) periodically reviewing our Code of Business Conduct and Ethics applicable to all directors, officers and employees and (3) monitoring compliance with the Code of Business Conduct and Ethics.

Compensation Committee

        The Compensation Committee currently consists of Paul J. Mitchell, David W. Anstice and Mark B. Skaletsky, each of whom is independent as defined in Rule 5605(a)(2) of the Nasdaq listing standards. Mr. Skaletsky serves as chair of the Compensation Committee. The Compensation Committee met thirteen times during fiscal year 2012.

        The Compensation Committee operates under a written charter adopted by the board of directors, a current copy of which can be found on the Corporate Governance tab of the Investors section of our website, available at: http://investor.alkermes.com. Under the terms of its current charter, the Compensation Committee is responsible for (1) discharging the Board's responsibilities relating to the compensation of our executives, (2) administering our incentive compensation and equity plans, (3) producing an annual report on executive compensation for inclusion in our proxy statement in accordance with applicable rules and regulations, and (4) reviewing and discussing with our management our executive compensation disclosure (including our disclosure under "Executive Compensation—Compensation Discussion and Analysis") included in reports and registration statements filed with the SEC. The primary objective of the Compensation Committee is to develop and implement compensation policies and plans that are appropriate for us and which provide incentives that further our long-term strategic plan and are consistent with our culture and the overall goal of enhancing our performance.

        The Compensation Committee has established procedures for the grant of options to eligible new employees. The Limited Compensation Sub-Committee, consisting of Mr. Skaletsky, acted by unanimous written consent during fiscal year 2012. The Limited Compensation Sub-Committee has the authority to make individual grants of stock options, up to the limit of its authority, to employees of the Company who are not subject to the reporting requirements of the Exchange Act and who are below the level of Vice President of the Company. The Limited Compensation Sub-Committee has generally approved new hire employee stock option grants of up to 15,000 shares per individual grant to such eligible employees.

        The Limited Compensation Sub-Committee will grant options to eligible new hires, within the limits of its authority, on the first Wednesday following the first Monday of each month (or the first business day thereafter if such day is a holiday) (the "New Hire Grant Date") for all eligible new hires beginning their employment the prior month. New hire grants that exceed the authority of the Limited Compensation Sub-Committee will be granted on the New Hire Grant Date or, if not possible, as soon as practicable thereafter, by the Compensation Committee as a whole.

Compensation Committee Interlocks and Insider Participation

        For fiscal year ending March 31, 2012, the following directors served on the Compensation Committee: Mark B. Skaletsky (Chair), Paul J. Mitchell and David W. Anstice.

        During the last fiscal year, none of our executive officers served as: (i) a member of the committee (or other committee of the board performing equivalent functions or, in the absence of any such committee, the entire board) of another entity, one of whose executive officers served on our Board committee; (ii) a director of another entity, one of whose executive officers served on our Board committee; or (iii) a member of the committee (or other committee of the board performing equivalent functions or, in the absence of any such committee, the entire board) of another entity, one of whose executive officers served as our director.

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 PROPOSAL 2

APPROVAL OF AMENDMENT TO
ALKERMES PLC 2011 STOCK OPTION AND INCENTIVE PLAN
TO INCREASE SHARES AUTHORIZED FOR ISSUANCE

(Ordinary resolution)

Overview

        In connection with the Business Combination, the Alkermes, Inc. Amended and Restated 2008 Stock Option and Incentive Plan was converted into and adopted as a plan of the Company entitled the Alkermes plc Amended and Restated 2008 Stock Option and Incentive Plan (the "Restated 2008 Plan").

        The Alkermes plc 2011 Stock Option and Incentive Plan was adopted by our Board on September 16, 2011, with subsequent amendments adopted by our Board on October 5, 2011 and October 31, 2011 (as amended, the "2011 Plan" and, together with the Restated 2008 Plan, the "Equity Plans"). The 2011 Plan was approved by our shareholders on December 8, 2011.

        Our Board is requesting shareholder approval of an amendment to the 2011 Plan to increase the number of ordinary shares authorized for issuance under the 2011 Plan by 4,200,000 ordinary shares (subject to adjustment for stock splits, stock dividends and similar events), for an aggregate of 12,550,000 ordinary shares available for issuance under the 2011 Plan, as amended in accordance with this proposal 2.

        The 2011 Plan, as amended in accordance with this proposal 2, is attached as Appendix A to this proxy statement and is incorporated herein by reference.

        As of the Record Date, approximately 5,338,120 ordinary shares remained available for future issuance under our Equity Plans, excluding those ordinary shares reserved for issuance upon exercise of outstanding options or vesting of outstanding restricted stock units. While some additional shares may become available under our Equity Plans such as through employee terminations, this number is not expected to be material.

        As of the Record Date, an aggregate of 19,428,377 ordinary shares are issuable upon exercise of outstanding options with a weighted average exercise price of $14.02 and a weighted average remaining term of 6.13 years; and 2,532,208 ordinary shares are subject to unvested restricted stock unit awards. As of the Record Date, we have a total of 130,703,377 ordinary shares outstanding.

Why do we believe our shareholders should approve an amendment to our 2011 Plan to increase the number of shares authorized for issuance thereunder?

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        The following table shows our historical dilution and burn rate percentages.

 
   For the fiscal year ended March 31,  
 
   2012   2011   2010  

Full Dilution(1)

     18.14 %   20.34 %   21.59 %

Adjusted Burn Rate(2)

     4.85 %   4.00 %   5.25 %

Unadjusted Burn Rate(3)

     4.08 %   3.11 %   4.16 %
(1)
Full dilution is calculated as (shares available for grant + shares subject to outstanding equity incentive awards)/(common stock outstanding + shares available for grant + share subject to outstanding equity incentive awards).

(2)
Adjusted Burn Rate is calculated as (shares subject to options granted + shares subject to other equity incentive awards granted, adjusted to reflect our fungible share ratio)/weighted average common shares outstanding.

(3)
Unadjusted Burn Rate is calculated as (shares subject to options granted + shares subject to other equity incentive awards granted, not adjusted to reflect our fungible share ratio)/weighted average common shares outstanding.

Outstanding Stock Option Awards

        The following table provides supplementary information with respect to stock options outstanding as of June 15, 2012. The exercisable options listed below have a weighted average exercise price less than the closing price of our ordinary shares on Nasdaq on March 30, 2012.

Year Granted
  Options
Outstanding 		  Options
Exercisable 		  Weighted Average
Exercise Price 		  Weighted Average
Contractual Term 		 

FY13*

     2,227,500     —   $ 16.55     9.94  

FY12

     3,685,600     440,773   $ 16.39     9.15  

FY11

     1,999,400     1,056,150   $ 12.17     7.98  

FY10

     2,308,136     1,469,886   $ 8.89     7.14  

FY09

     1,376,525     1,285,025   $ 12.08     6.08  

FY08

     1,022,500     1,022,500   $ 15.58     5.11  

FY07

     1,338,025     1,338,025   $ 16.89     4.11  

FY06

     1,297,710     1,297,710   $ 18.40     3.32  

FY05

     2,032,764     2,032,764   $ 14.01     2.35  

FY04

     1,468,243     1,468,243   $ 12.42     1.27  

FY03

     671,974     671,974   $ 6.78     0.39  

Total

     19,428,377     12,083,050              
*
Reflects option awards granted through June 15, 2012. This includes annual equity awards made to employees on May 18, 2012.

Important Aspects of our 2011 Plan Designed to Protect our Shareholders' Interests

        The 2011 Plan contains certain provisions that are designed to protect our shareholders' interests and reflect corporate governance best practices including those set forth below.

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Recommendation

        The text of the resolution in respect of Proposal 2 is as follows:

        The Board unanimously recommends that you vote FOR approval of the amendment to the 2011 Plan to increase the number of ordinary shares authorized for issuance thereunder.

Principal Features of the 2011 Plan

        The material features of the 2011 Plan are as set forth below.

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        Based solely on the closing price of our ordinary shares as reported on Nasdaq on the Record Date, the aggregate market value of the 12,550,000 shares, representing the maximum number of ordinary shares to be issued under the 2011 Plan, as amended in accordance this proposal 2, is US$196,784,000. Shares tendered or held back upon exercise of an option or settlement of an award to cover the exercise price or tax withholding are not available for future issuance under the 2011 Plan. The shares issued by us under the 2011 Plan will be authorized but unissued shares.

        To ensure that certain awards granted under the 2011 Plan to a "Covered Employee" (as defined in the Code) qualify as "performance-based compensation" under Section 162(m) of the Code, the 2011 Plan provides that the Administrator may require that the vesting or grant of such awards be conditioned on the satisfaction of performance criteria that may include any or all of the following: (1) earnings before interest, taxes, depreciation and amortization, (2) net income (loss) (either before or after interest, taxes, depreciation and/or amortization), (3) changes in the market price of our ordinary shares, (4) economic value-added, (5) initiation or completion of clinical trials, (6) results of clinical trials, (7) drug development or commercialization milestones, (8) collaboration milestones, (9) operational measures including production capacity and capability, (10) hiring and retention of key managers, (11) expense management, (12) capital raising transactions, (13) sales or revenue, (14) acquisitions or strategic transactions, (15) operating income (loss), (16) cash flow (including, but not limited to, operating cash flow and free cash flow), (17) return on capital, assets, equity, or investment, (18) shareholder returns, (19) gross or net profit levels, (20) operating margins, (21) earnings (loss) per ordinary share and (22) sales or market shares, any of which may be measured either in absolute terms or as compared to any incremental increase or as compared to results of a peer group. The Administrator will select, within 90 days following the commencement of a performance cycle, the particular performance criteria for such award and the performance goals with respect to each performance criterion. Each such award will specify the amount payable, or the formula for determining the amount payable, upon achievement of the various applicable performance targets. Subject to adjustments for stock splits and similar events, the maximum award granted to any one individual that is intended to qualify as "performance-based compensation" under Section 162(m) of the Code will not exceed 4,000,000 ordinary shares for any performance cycle. If a performance-based award is payable in cash to any executive, it cannot exceed US$25 million for any performance cycle.

Summary of the 2011 Plan

        The following description of certain features of the 2011 Plan, as amended in accordance with this proposal 2, is intended to be a summary only. The summary is qualified in its entirety by the full text of the 2011 Plan, as amended in accordance with this proposal 2, attached hereto as Appendix A.

        Plan Administration.    The Administrator has full power to select, from among the individuals eligible for awards, the individuals to whom awards will be granted, to make any combination of awards to participants, and to determine the specific terms and conditions of each award, subject to the provisions of the 2011 Plan. The Administrator may delegate to a subcommittee comprised of one or more members of the Board all or part of the Administrator's authority and duties with respect to the granting of Options to employees who are not subject to the reporting and other provisions of Section 16 of the Exchange Act. Any such delegation by the Administrator shall include a limitation as to the amount of Options that may be granted during the period of the delegation and shall contain guidelines as to the determination of the exercise price and the vesting criteria.

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        Eligibility and Limitations on Grants.    Persons eligible to participate in the 2011 Plan will be those officers, employees, non-employee directors and other key persons (including consultants and prospective employees) of the Company and its subsidiaries as selected from time to time by the Administrator. The intention in making awards to eligible persons under the 2011 Plan will be to align the compensation of these individuals over a multi-year period directly with the interests of our shareholders and serve as a tool in the recruiting and retention of these individuals.

        The maximum award of stock options granted to any one individual will not exceed 4,000,000 ordinary shares (subject to adjustment for stock splits and similar events) for any calendar year period. The maximum number of ordinary shares that can be awarded in the form of incentive stock options under the 2011 Plan, as amended, will not exceed 12,550,000 (subject to adjustment for stock splits and similar events).

        Stock Options granted to employees and key persons.    The 2011 Plan permits the granting of (1) stock options intended to qualify as incentive stock options under Section 422 of the Code and (2) stock options that do not so qualify. Options granted under the 2011 Plan will be non-qualified options if they fail to qualify as incentive options or exceed the annual limit on incentive stock options. Non-qualified options may be granted to any persons eligible to receive incentive options and to non-employee directors and key persons. The option exercise price of each option will be determined by the Administrator but may not be less than 100% of the fair market value of our ordinary shares on the date of grant.

        The term of each option will be fixed by the Administrator and may not exceed ten years from the date of grant. The Administrator will determine at what time or times each option may be exercised. Options may be made exercisable in installments and the exercisability of options may be accelerated by the Administrator. Options may be exercised in whole or in part with written or electronic notice to the Company's delegate. Upon exercise of non-qualified stock options, unless otherwise determined by the Administrator, the purchase price must be paid through a net reduction in the number of ordinary shares issuable upon such exercise, based on the fair market value of our ordinary shares on the date of exercise. Upon exercise of incentive stock options and those non-qualified options for which the Administrator elects not to utilize the above payment method, the option exercise price may be paid in full either in cash, by certified or bank check or other instrument acceptable to the Administrator or by delivery (or attestation to the ownership) of ordinary shares that are beneficially owned by the optionee based on the fair market value of our ordinary shares on the date of exercise or, subject to applicable law, by delivery to the Company of an exercise notice together with irrevocable instructions to a broker to promptly deliver cash or a check payable to the Company for the purchase price.

        To qualify as incentive options, options must meet additional federal tax requirements, including a US$100,000 limit on the value of our ordinary shares subject to incentive options that first become exercisable by a participant in any one calendar year.

        Stock Options granted to non-employee directors.    The 2011 Plan provides that (a) upon becoming a member of the Board, each non-employee director who is not then a consultant to us shall be granted on such day a non-qualified stock option to acquire 35,000 ordinary shares, which shall vest ratably over the three calendar years following the date of grant, plus an additional stock option to acquire a number of our ordinary shares equal to the product of 25,000 multiplied by a fraction, the numerator of which equals the number of months remaining until the next annual meeting of shareholders of the Company and the denominator of which equals 12, which shall vest on the first anniversary of the date of grant, and (b) each non-employee director who is serving as a director of the Company on each annual meeting of shareholders, beginning with the 2012 Annual General Meeting of Shareholders, shall automatically be granted on such day a non-qualified stock option to acquire 25,000 of our ordinary shares, which shall vest on the first anniversary of the date of grant; provided, however, that no grant shall be made to an individual who ceases to be a member of the Board on such day. The Administrator may grant additional non-qualified stock options to our non-employee directors and such

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grants may vary among individual non-employee directors. The option exercise price of each option will be determined by the Administrator but may not be less than 100% of the fair market value of our ordinary shares on the date of grant.

        The term of each option may not exceed ten years from the date of grant. Options may be exercised only by notice to the Company or the Company's delegate specifying the number of ordinary shares to be purchased. Upon exercise of options, the option exercise price will be paid in the same manner as described above under "Stock Options granted to employees and key persons."

        Grants of stock options to our non-employee directors will initially consist of options in respect of ordinary shares reserved and available for issuance pursuant to our Restated 2008 Plan. If and when no ordinary shares remain available for issuance under our Restated 2008 Plan, then such non-employee director grants will consist of options in respect of ordinary shares reserved and available for issuance under our 2011 Plan and will be as follows:

        Restricted Stock Unit Awards.    The Administrator may award stock units as restricted stock unit awards to participants. Restricted stock unit awards are ultimately payable in the form of ordinary shares and may be subject to such conditions and restrictions as the Administrator may determine. These conditions and restrictions may include the achievement of certain performance goals and/or continued employment with the Company through a specified vesting period. However, in the event these awards granted to employees have a performance-based goal, the restriction period will be at least one year, and in the event these awards granted to employees have a time-based restriction, the restriction period will be at least three years, but vesting can occur incrementally over the three-year period. The Administrator may waive the foregoing restriction in the case of a grantee's death, disability or retirement or upon a sale event (as defined in the 2011 Plan). To the extent a Restricted Stock Unit Award is subject to Section 409A of the Code, it may contain such additional terms and conditions as the Administrator shall determine in order for such Award to comply with the requirements of Section 409A.

        The Administrator, in its sole discretion, may permit a grantee to elect to receive a portion of future cash compensation otherwise due to such grantee in the form of a Restricted Stock Unit Award. Any such election shall be made in writing and shall be delivered to the Company no later than the date specified by the Administrator and in accordance with Section 409A and such other rules and procedures established by the Administrator. Any such future cash compensation that the grantee elects to defer shall be converted to a fixed number of phantom stock units (which may be fully vested) based on the fair market value of our ordinary shares on the date the compensation would otherwise have been paid to the grantee if such payment had not been deferred.

        Restricted Stock.    The Administrator may award ordinary shares to participants subject to such conditions and restrictions as the Administrator may determine. These conditions and restrictions may include the achievement of certain performance goals and/or continued employment with us through a specified restricted period. However, in the event these awards granted to employees have a performance-based restriction, the restriction period will be at least one year, and in the event these awards granted to employees have a time-based restriction, the restriction will be at least three years, but vesting can occur incrementally over the three-year period. The Administrator may waive the foregoing restriction in the case of a grantee's death, disability or retirement or upon a sale event (as defined in the 2011 Plan).

        Cash-based Awards.    Each cash-based award shall specify a cash-denominated payment amount, formula or payment ranges as determined by the Administrator. Payment, if any, with respect to a cash-based award may be made in cash or in ordinary shares, as the Administrator determines. Except as may otherwise be provided by the Administrator, a grantee's right in all cash-based awards that have not vested shall automatically terminate upon the grantee's termination of employment (or cessation of service relationship) with the Company and its subsidiaries for any reason (including if a subsidiary ceases to be a subsidiary of the Company).

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        Performance Share Awards.    The Administrator may grant performance share awards independent of, or in connection with, the granting of other awards under the 2011 Plan. The Administrator, in its sole discretion, determines whether and to whom performance share awards will be granted, the performance goals subject to the award, the period during which performance is to be measured, which may not be less than one year, and such other conditions as the Administrator shall determine. Upon the attainment of the performance goal, the grantee is entitled to receive ordinary shares.

        Tax Withholding.    Participants in the 2011 Plan are responsible for the payment of any federal, national, state or local taxes that we are required by law to withhold upon any option exercise or vesting of other awards. The Company has the right to deduct any such taxes from any payment otherwise due to grantee, including the right to reduce the number of ordinary shares otherwise required to be issued to a grantee in an amount that, on the date of issuance, would have a fair market value equal to all such taxes required to be withheld by the Company.

        Change in Control Provisions.    Under the 2011 Plan, in the case of and subject to the consummation of a sale event (as defined in the 2011 Plan), except as the Administrator may otherwise specify with respect to a particular award in the relevant award documentation, all stock options that are not exercisable immediately prior to the effective time of the sale event shall become fully exercisable as of the effective time of the sale event, all other awards with time-based vesting, conditions or restrictions shall become fully vested and nonforfeitable as of the effective time of the sale event and all awards with conditions and restrictions relating to the attainment of performance goals may become vested and nonforfeitable in connection with a sale event in the Administrator's discretion. In addition, in the event of a sale event in which the Company's shareholders will receive cash consideration, the Company may make or provide for a cash payment to participants holding stock options equal to the difference between the per share cash consideration and the exercise price of such options.

        Amendments and Termination.    Our Board may at any time amend or discontinue the 2011 Plan and the Administrator may at any time amend or cancel any outstanding award for the purpose of satisfying changes in the law or for any other lawful purpose. However, no such action may adversely affect any rights under any outstanding award without the holder's consent. Any amendments that materially change the terms of the 2011 Plan, including any amendments that increase the number of ordinary shares reserved for issuance under the 2011 Plan, expand the types of awards available, materially expand the eligibility to participate in, or materially extend the term of, the 2011 Plan, or materially change the method of determining the fair market value of our ordinary shares, will be subject to approval by our shareholders. Amendments shall also be subject to approval by our shareholders if and to the extent determined by the Administrator to be required by the Code to preserve the qualified status of incentive options or to ensure that compensation earned under the 2011 Plan qualifies as performance-based compensation under Section 162(m) of the Code. In addition, except in connection with a reorganization or other similar change in the capital stock of the Company or a merger or other transaction, without prior shareholder approval the Administrator may not reduce the exercise price of an outstanding stock option or effect re-pricing of an outstanding stock option through cancellation or re-grants.

Effective Date of 2011 Plan

        The 2011 Plan became effective on December 8, 2011 upon approval by our shareholders. Awards of incentive options may be granted under the 2011 Plan until ten years after Board approval. No awards may be granted under the 2011 Plan after the date that is ten years from the date of shareholder approval.

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New Plan Benefits

        Except as set forth below for our non-employee directors, the benefits or amounts that may be received by, or allocated to, the Company's Chief Executive Officer, Chief Financial Officer, and the three other named executive officers, all executives as a group, non-executive directors as a group, and non-executive officer employees as a group are granted on a discretionary basis and, as such, are not determinable as awards under the 2011 Plan.

        Grants of stock options to our non-employee directors will initially consist of options in respect of ordinary shares reserved and available for issuance pursuant to our Restated 2008 Plan. If and when no ordinary shares remain available for issuance under our Restated 2008 Plan, then such non-employee director grants will consist of options in respect of ordinary shares reserved and available for issuance under our 2011 Plan.

U.S. Federal Income Tax Consequences

        The following is a summary of the principal U.S. federal income tax consequences of certain transactions under the 2011 Plan. It does not describe all U.S. federal tax consequences under the 2011 Plan, nor does it describe state or local tax consequences.

        Incentive Options.    No taxable income is generally realized by the optionee upon the grant or exercise of an incentive option. If ordinary shares issued to an optionee pursuant to the exercise of an incentive option are sold or transferred after two years from the date of grant and after one year from the date of exercise, then (1) upon sale of such shares, any amount realized in excess of the option price (the amount paid for the shares) will be taxed to the optionee as a long-term capital gain, and any loss sustained will be a long-term capital loss, and (2) we will not be entitled to any deduction for federal income tax purposes. The exercise of an incentive option will give rise to an item of tax preference that may result in alternative minimum tax liability for the optionee.

        An incentive option will not be eligible for the tax treatment described above if it is exercised more than three months following termination of employment (or one year in the case of termination of employment by reason of disability). In the case of termination of employment by reason of death, the three-month rule does not apply. If ordinary shares acquired upon the exercise of an incentive option are disposed of prior to the expiration of the two-year and one-year holding periods described above, generally (1) the optionee will realize ordinary income in the year of disposition in an amount equal to the excess (if any) of the fair market value of the ordinary shares at exercise (or, if less, the amount realized on a sale of such shares) over the option price thereof, and (2) we will be entitled to deduct such amount. Special rules will apply where all or a portion of the exercise price of the incentive option is paid by tendering shares.

        Non-Qualified Options.    No taxable income is generally realized by the optionee upon the grant of a non-qualified option. Generally (1) at exercise, ordinary income is realized by the optionee in an amount equal to the difference between the option price and the fair market value of the shares on the date of exercise, and we receive a tax deduction for the same amount, and (2) at disposition, appreciation or depreciation after the date of exercise is treated as either short-term or long-term capital gain or loss depending on how long the shares have been held. Special rules will apply where all or a portion of the exercise price of the non-qualified option is paid by tendering shares. Upon exercise, the optionee will also be subject to Social Security taxes on the excess of the fair market value over the exercise price of the option.

Parachute Payments

        The vesting of any portion of an option or other award that is accelerated due to the occurrence of a change in control may cause a portion of the payments with respect to such accelerated awards to

32

be treated as "parachute payments" as defined in the Code. Any such parachute payments may be non-deductible to us, in whole or in part, and may subject the recipient to a non-deductible 20% federal excise tax on all or a portion of such payment (in addition to other taxes ordinarily payable).

Limitation on the Company's Deductions

        As a result of Section 162(m) of the Code, our deduction for certain awards under the 2011 Plan may be limited to the extent that the Chief Executive Officer or other executive officer (other than our Chief Financial Officer) whose compensation is required to be reported in the summary compensation table receives compensation in excess of US$1 million a year (other than performance-based compensation that otherwise meets the requirements of Section 162(m) of the Code). The 2011 Plan is structured to allow certain grants to qualify as performance-based compensation.

        A copy of the 2011 Plan, as amended in accordance with this proposal 2, is attached as Appendix A.

33


 PROPOSAL 3

ADVISORY VOTE ON EXECUTIVE COMPENSATION

(Ordinary resolution)

        Our Compensation Discussion and Analysis, which appears later in this proxy statement, describes our executive compensation program and the compensation decisions that the Compensation Committee made with respect to the compensation of our named executive officers (listed in the Summary Compensation Table) for fiscal year 2012. The vote is not intended to address any specific item of compensation, but rather the overall compensation of our named executive officers and the philosophy, policies and practices described in this proxy statement. As required pursuant to Section 14A of the Exchange Act, our Board is asking that shareholders cast a non-binding, advisory vote FOR the following resolution:

        "RESOLVED, that the Company's shareholders approve, on an advisory basis, the compensation paid to the Company's named executive officers, as disclosed in this proxy statement pursuant to Item 402 of Regulation S-K, including the Compensation Discussion and Analysis, and related compensation tables and narrative discussion."

        Our Board is asking that shareholders support this proposal. Although the vote you are being asked to cast is advisory, and therefore non-binding, we value the views of our shareholders, and the Compensation Committee will consider the outcome of the vote when making future compensation decisions for our named executive officers.

        The Board unanimously recommends that you vote FOR the advisory vote on executive compensation.

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 PROPOSAL 4

ADVISORY VOTE ON FREQUENCY OF
ADVISORY VOTE ON EXECUTIVE COMPENSATION

        Proposal 3 above requests that you cast an advisory vote for the compensation disclosed in this proxy statement that we paid to our named executive officers for fiscal year 2012. That advisory vote is referred to as a "say-on-pay" vote. In this Proposal 4, as required pursuant to Section 14A of the Exchange Act, our Board is asking that shareholders cast a non-binding, advisory vote on how frequently we should have say-on-pay votes in the future. You can vote to hold say-on-pay votes every one, two or three years, or you can abstain from voting.

        Our Board believes that say-on-pay votes should be held annually to give shareholders the opportunity to provide regular input on our executive compensation programs and increase our Board's accountability for its compensation decisions and therefore recommends that shareholders vote for the one year option. This vote, like the say-on-pay vote itself, is non-binding. If a choice other than one year receives the most votes, our Board of Directors will take the voting results into consideration in determining how frequently we will present you with a say-on-pay vote.

        The Board recommends that you vote FOR the one-year option as the frequency of the advisory vote on executive compensation.

35


 PROPOSAL 5

AUTHORIZATION TO HOLD THE 2013 ANNUAL GENERAL MEETING OF SHAREHOLDERS OF THE COMPANY AT A LOCATION OUTSIDE OF IRELAND

(Ordinary resolution)

        Under Section 140 of the Companies Act, 1963 and in accordance with article 75 of our Articles of Association, the shareholders of the Company may authorize the holding of any Annual General Meeting of shareholders at a location outside of Ireland. The Board may determine to hold the Annual General Meeting of shareholders for the fiscal year ending March 31, 2013 (the "2013 Annual General Meeting") outside of Ireland, and is therefore asking our shareholders to authorize holding the 2013 Annual General Meeting of Shareholders at a location outside of Ireland.

        The text of the resolution in respect of Proposal 4 is as follows:

        "RESOLVED, that the Annual General Meeting of Shareholders for the fiscal year ending March 31, 2013 may be held at such place outside Ireland as may be determined by the Directors."

        The Board unanimously recommends that you vote FOR the authorization to hold the 2013 Annual General Meeting of Shareholders of Alkermes plc at a location outside of Ireland.

36


 PROPOSAL 6

APPOINTMENT OF INDEPENDENT AUDITORS AND AUTHORIZATION
OF AUDIT AND RISK COMMITTEE TO SET AUDITORS' REMUNERATION

(Ordinary resolution)

        PricewaterhouseCoopers ("PwC") served as our independent auditors for the fiscal year ended March 31, 2012. The Audit and Risk Committee of the Board has retained PwC to serve as independent auditor for the fiscal year ending March 31, 2013. The Audit and Risk Committee reviewed and discussed the performance of PwC as the Company's independent auditor for fiscal year ending March 31, 2012. Although we are not required to submit the appointment of PwC for shareholder approval, as a matter of good corporate governance, the Board, upon the recommendation of the Audit and Risk Committee, has determined to submit its selection for approval by shareholders and to ask that shareholders authorize the Audit and Risk Committee to set the auditor's remuneration. If the selection of PwC is approved, the Audit and Risk Committee, in its discretion, may still select a different independent registered public accounting firm at any time during the year if it determines that such a change would be in the best interests of the Company and its shareholders.

        A representative of PwC is expected to be present at the Annual General Meeting and will be given the opportunity to make a statement, if he or she so desires, and to respond to appropriate questions.

        The Board unanimously recommends that you vote FOR the appointment of PricewaterhouseCoopers as the Company's independent auditor for the fiscal year ending March 31, 2013 and the authorization of the Audit and Risk Committee of the Board to set the auditor's remuneration.

37


 REPORT OF THE AUDIT AND RISK COMMITTEE

        No portion of this audit committee report shall be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, through any general statement incorporating by reference in its entirety the proxy statement in which this report appears, except to the extent that the Company specifically incorporates this report or a portion of it by reference. In addition, this report shall not be deemed filed under either the Securities Act or the Exchange Act.

        As more fully described in its charter, the Audit and Risk Committee oversees Alkermes' financial reporting process on behalf of the Board of Directors. Management has day-to-day responsibility for the Company's financial reporting process, including assuring that the Company develops and maintains adequate financial controls and procedures and monitoring and assessing compliance with those controls and procedures, including internal control over financial reporting. Alkermes' independent auditors are responsible for auditing the annual financial statements prepared by management, expressing an opinion as to whether those financial statements fairly present the financial position, results of operations and cash flows of the Company in conformity with generally accepted accounting principles and discussing with the Audit and Risk Committee any issues they believe should be raised. The independent auditors are also responsible to the Audit and Risk Committee and the Board for testing the integrity of the financial accounting and reporting control systems, for issuing a report on the Company's internal control over financial reporting and for such other matters as the Audit and Risk Committee and Board determine. In addition, the independent auditors perform audit-related and permissible non-audit services for the Company.

        In the performance of its oversight function, the Audit and Risk Committee reviewed and discussed with management and the independent auditors the audited consolidated financial statements of the Company, as of and for the fiscal year ended March 31, 2012, contained in Alkermes plc's Annual Report on Form 10-K. The Audit and Risk Committee discussed with PwC, Alkermes plc's independent auditors, the overall scope and plans for their audit. The Audit and Risk Committee met with PwC, with and without management present, to discuss the results of its examination, judgments as to the quality, not just the acceptability, of the Company's accounting principles, the reasonableness of significant estimates and judgments, critical accounting policies and accounting estimates resulting from the application of these policies, the substance and clarity of disclosures in the financial statements, and the Company's disclosure control process and internal control over financial reporting.

        The Audit and Risk Committee also discussed with PwC the matters required to be discussed by Statement on Auditing Standards No. 61, as amended (AICPA, Professional Standards, Vol. 1, AU section 380), as adopted by the PCAOB in Rule 3200T (Communications with Audit Committees), as currently in effect. In addition, the Audit and Risk Committee discussed with PwC the independence of PwC from management and Alkermes, and received the written disclosures and the letter from PwC to confirm its independence as required by applicable requirements of the PCAOB.

        The Audit and Risk Committee also reviewed and discussed with management its assessment and report on the effectiveness of the Company's internal control over financial reporting as of March 31, 2012, which it made in response to the requirements set forth in Section 404 of the Sarbanes-Oxley Act and related regulations. The Audit and Risk Committee also reviewed and discussed with PwC the Report of Independent Registered Public Accounting Firm included in the Company's Annual Report on Form 10-K related to its audit of the consolidated financial statements and the effectiveness of internal control over financial reporting.

        The Audit and Risk Committee monitors the activity and performance of PwC. All services to be provided by PwC are pre-approved by the Audit and Risk Committee. The Audit and Risk Committee's evaluation of PwC included, among other things, consideration as to whether PwC's provision of permissible non-audit services to the Company is compatible with maintaining its independence.

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        In reliance on these reviews and discussions, the Audit and Risk Committee recommended to the Board of Directors that the audited consolidated financial statements be included in Alkermes plc's Annual Report on Form 10-K for the fiscal year ended March 31, 2012 for filing with the SEC, and the Board of Directors approved such inclusion.

Respectfully submitted by the Audit and Risk Committee,

Paul J. Mitchell, Chair
Floyd E. Bloom
Mark B. Skaletsky

        For more information about our Audit and Risk Committee and its charter, you are invited to access the Corporate Governance page of the Investors section of the Company's website, available at: http://investor.alkermes.com.

39


 AUDIT FEES

Aggregate fees for fiscal year 2012 and fiscal year 2011

        During the years ended March 31, 2012 and 2011, PwC provided various audit, audit-related and tax services to us. The Audit and Risk Committee understands the need for PwC to maintain objectivity and independence in its audit of our financial statements and our internal control over financial reporting. To minimize relationships that could appear to impair the objectivity of PwC, our Audit and Risk Committee has adopted policies and procedures which require it to pre-approve all audit and non-audit services performed by PwC. All of the services of PwC for 2012 and 2011 described below were pre-approved by the Audit and Risk Committee.

        The aggregate fees of PwC for the years ended March 31, 2012 and 2011 are as follows:

 
   2012   2011  

Audit fees:

              

Audit and review of financial statements(1)

   $ 1,514,654   $ 579,112  

Audit-related fees(2)

     598,592     66,000  

Tax fees(3)

     1,167,362     245,824  

All other fees(4)

     8,020     1,500  
           

Total

   $ 3,288,628   $ 892,436  
           
(1)
In the year ended March 31, 2012, consists of fees for services related to the audit of our annual consolidated financial statements, statutory audits, and the review of our quarterly consolidated financial statements, including the review of our internal controls over financial reporting as well as procedures related to our S-4 and S-1 registration filings. In the year ended March 31, 2011, consists of fees for services related to the audit of our annual consolidated financial statements and the review of our quarterly consolidated financial statements, including the review of our internal controls over financial reporting.

(2)
In the year ended March 31, 2012, consists of fees for due diligence procedures performed in connection with the acquisition of EDT and a royalty audit of one of our collaboration agreements. In the year ended March 31, 2011, consists of fees for audit procedures performed in connection with one of our collaboration agreements.

(3)
In the years ended March 31, 2012 and 2011, consists of fees for tax advisory services, primarily related to the acquisition of EDT, other than those related to the audit of our annual consolidated financial statements and review of our quarterly consolidated financial statements.

(4)
In the year ended March 31, 2012, consists of fees for remuneration surveys performed for our Irish entity and payment for access to the PWC on-line accounting research database. In the year ended March 31, 2011, consists of fees for access to the PWC on-line accounting research database.

        Total fees paid to PWC Ireland in respect of the audit of the group accounts were $0.5 million during the year ended March 31, 2012. In addition, PWC Ireland received $0.6 million for tax advisory services during the year ended March 31, 2012 and less than $0.1 million in all other fees.

40


 OWNERSHIP OF THE COMPANY'S ORDINARY SHARES

        The following table and notes provide information about the beneficial ownership of our ordinary shares as of the Record Date by:

        According to Securities and Exchange Commission rules, the Company has included in the column "Number of Issued Ordinary Shares" all shares over which the person has sole or shared voting or investment power, and the Company has included in the column "Number of Ordinary Shares Issuable" all shares that the person has the right to acquire within 60 days after June 15, 2012 through the exercise of any stock option, vesting of any stock award or other right. All shares that a person has a right to acquire within 60 days of June 15, 2012 are deemed outstanding for the purpose of computing the percentage beneficially owned by the person, but are not deemed outstanding for the purpose of computing the percentage beneficially owned by any other person.

        Unless otherwise indicated, each person has the sole power (except to the extent authority is shared by spouses under applicable law) to invest and vote the shares listed opposite the person's name. The Company's inclusion of shares in this table as beneficially owned is not an admission of beneficial ownership of those shares by the person listed in the table. The business address of each director and that of Shane Cooke and James M. Frates is Connaught House, 1 Burlington Road, Dublin 4, Ireland. The business address of James L. Botkin is 1300 Gould Drive, Gainesville, Georgia 30504. The business address of the other executive officers is 852 Winter Street, Waltham, MA 02451.

Ownership by Directors and Executive Officers

Directors and Executive Officers
  Number of Issued
Ordinary Shares 		  Number of
Ordinary Shares
Issuable(1) 		  Total   Percent(2)  

David W. Anstice

     10,000     80,000     90,000     *  

Floyd E. Bloom

     120,375     180,000     300,375     *  

Robert A. Breyer

     58,106     150,400     208,506     *  

Wendy L. Dixon

     —     35,000     35,000     *  

Geraldine A. Henwood

     —     140,000     140,000     *  

Paul J. Mitchell

     8,000     188,000     196,000     *  

Richard F. Pops

     348,173     2,813,750     3,161,923     2.42 %

Mark B. Skaletsky

     5,000     159,000     164,000     *  

Shane Cooke

     —     —     —     —  

Elliot W. Ehrich

     24,466     491,900     516,366     *  

James M. Frates

     90,092     748,212     838,304     *  

Gordon G. Pugh

     31,774     459,050     490,824     *  

All directors and executive officers as a group (16 individuals in total)

     843,956     6,451,312     7,295,268     5.58 %
*
Represents less than one percent (1%) of our outstanding ordinary shares.

41

(1)
Shares that can be acquired through stock options exercisable and restricted stock unit awards vesting by August 14, 2012, which is 60 days from the Record Date.

(2)
Applicable percentage of ownership as of the Record Date is based upon 130,703,377 ordinary shares outstanding.

Ownership By Principal Shareholders

        The following table and notes provides information about the beneficial ownership of our ordinary shares as of the Record Date, or as of the date otherwise set forth below, by each shareholder known to us to be the beneficial owner of more than 5% of our ordinary shares.

        Beneficial ownership is determined under the rules of the SEC and generally includes voting or investment power over securities. Except in cases where community property laws apply or as indicated in the footnotes to this table, it is believed that each shareholder identified in the table possesses sole voting and investment power over all of our ordinary shares shown as beneficially owned by that shareholder. Percentage of beneficial ownership is based on Schedule 13D and Schedule 13G filings made with the SEC as of June 15, 2012. Percentage of beneficial ownership is based on 130,703,377 of our ordinary shares outstanding as of the Record Date.

Name and Address of Beneficial Owner
  Number of
Ordinary Shares
Beneficially Owned 		  Percent  

Shareholders Owning 5% or more:

              

Elan Corporation, plc(1)

     7,750,000     5.9 %

Treasury Building
Lower Grand Canal Street
Dublin 2
Ireland

              

T. Rowe Price Associates, Inc.(2)

     15,528,790     11.9 %

100 E. Pratt Street
Baltimore, MD 21202

              

FMR LLC(3)

     16,960,050     13.0 %

82 Devonshire Street
Boston, MA 02109

              

Wellington Management Company, LLP(4)

     17,069,952     13.1 %

75 State Street
Boston, MA 02109

              
(1)
Based solely on a Schedule 13D/A dated March 14, 2012, Elan and the Elan Shareholder (together, the Elan Shareholder and Elan, the "Elan Reporting Parties") may be deemed to beneficially own 7,750,000 ordinary shares. The number of ordinary shares as to which each of the Elan Reporting Parties shares the power to vote or direct the vote is 7,750,000. The number of ordinary shares as to which each of the Elan Reporting Parties shares the power to dispose or direct the disposition of is 7,750,000. The number of ordinary shares as to which each of the Elan Reporting Parties has the sole power to vote or direct the vote, or dispose or direct the disposition is zero. Elan is a neuroscience-based biotechnology company focused on discovering and developing advanced therapies in neurodegenerative and autoimmune diseases. The Elan Shareholder is an indirect wholly owned subsidiary of Elan.


The shares were originally acquired pursuant to the Business Combination, effective September 16, 2011. The Elan Reporting Parties together acquired common beneficial ownership over the ordinary shares and hold such shares pursuant to the Shareholder's Agreement (the "Shareholder's

42


Pursuant to an Underwriting Agreement (the "Underwriting Agreement"), dated as of March 8, 2012, by and among the Elan Shareholder, the Company and the several underwriters party thereto, on March 13, 2012, the Elan Shareholder sold 24,150,000 Shares in a marketed underwritten registered offering (the "Registered Offering") (including 3,150,000 Shares sold pursuant to the full exercise of an option to purchase such amount of Shares granted to the underwriters pursuant to the Underwriting Agreement) at a price per share of $15.79875, which represents a price to the public of $16.50 per share less the underwriting discount. The Shares were sold in the Registered Offering pursuant to a shelf registration statement on Form S-1 filed by the Company with the SEC in connection with the resale of the Shares by the Elan Shareholder, which the SEC declared effective on March 2, 2012. Under the terms of the Underwriting Agreement, the Elan Shareholder has agreed that, subject to certain exceptions, for a period of 90 days from the date of the Underwriting Agreement, the Elan Shareholder and its affiliates will not, without the prior written consent of the managing underwriters, dispose of or hedge any shares or any securities convertible into or exchangeable for the Ordinary Shares. The managing underwriters in their sole discretion may release any of the securities subject to these lock-up agreements at any time without notice. Notwithstanding the foregoing, if (i) during the last 17 days of the 90-day restricted period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or (ii) prior to the expiration of the 90-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 90-day restricted period, the restrictions described above shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.


Under the terms of the Underwriting Agreement, the Elan Shareholder agreed to indemnify the underwriters against certain liabilities, including certain liabilities under the Securities Act of 1933, as amended, or to contribute to payments the underwriters may be required to make because of any of those liabilities.

Under the terms of the Shareholder's Agreement, the Elan Shareholder is subject to certain restrictions on its ability to transfer the Shares without the Company's consent. Two Waiver and Consent Letters (the "Waiver and Consent Letters") to the Shareholder's Agreement were executed by the Parties on March 7, 2012 and March 8, 2012, pursuant to which the Company (i) agreed to waive the limitations that would prohibit both a transfer of the Shares prior to the six (6) month anniversary of the Closing Date (as defined in the Shareholder's Agreement), and following such date, the transfer of more than 40.75% of the Shares in the Registered Offering and (ii) agreed and consented to the sale of the 24,150,000 Shares by the Elan Shareholder in the Registered Offering.


Under the terms of the Shareholder's Agreement, Elan is subject to a standstill provision until September 16, 2021. The standstill provision generally prevents Elan from acquiring any more of our ordinary shares and from taking a number of actions that might result in Elan exerting influence or control over us. The standstill provisions will terminate early on certain events, including a decision by us to publicly seek, recommend or engage in a transaction that would result in our change of control.


Under the Shareholder's Agreement, the Elan Shareholder has agreed to vote on all matters in accordance with the recommendation of our board of directors until at least September 16, 2012.

43


Under the Shareholder's Agreement, Elan has certain customary registration rights, including demand (including shelf) and piggyback registration rights with respect to transfers of our ordinary shares. The registration rights terminate July 13, 2012 or sooner in certain circumstances.

(2)
Based solely on a Schedule 13G filed April 10, 2012, T. Rowe Price Associates, Inc., in its capacity as investment adviser, may be deemed to beneficially own 15,528,790 ordinary shares of Alkermes. T. Rowe Price Associates, Inc. has sole voting power over 3,294,420 ordinary shares of Alkermes and has sole dispositive power over 15,528,790 ordinary shares of Alkermes. The number of ordinary shares as to which T. Rowe Price Associates, Inc. has shared power to vote or direct the vote, or dispose or direct the disposition is zero.

(3)
Based solely on a Schedule 13G/A dated February 14, 2011, FMR LLC, a parent holding company, has sole voting power over 5,970 ordinary shares of Alkermes and sole investment power over 16,960,050 ordinary shares of Alkermes. Of the shares reported as beneficially owned by FMR LLC:

•
Fidelity Management & Research Company ("Fidelity"), a wholly owned subsidiary of FMR LLC and an investment adviser registered under Section 203 of the Investment Advisers Act of 1940, is the beneficial owner of 16,958,380 ordinary shares of Alkermes as a result of acting as investment adviser to various investment companies registered under Section 8 of the Investment Company Act of 1940.

•
The ownership of one investment company, Fidelity Growth Company Fund, amounted to 12,207,261 ordinary shares of Alkermes. Edward C. Johnson 3d and FMR LLC, through its control of Fidelity, and the funds each has sole power to dispose of the 16,958,380 ordinary shares owned by the Funds.

•
Members of the family of Edward C. Johnson 3d, Chairman of FMR LLC, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders' voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders' voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC. Neither FMR LLC nor Edward C. Johnson 3d, Chairman of FMR LLC, has the sole power to vote or direct the voting of the shares owned directly by the Fidelity Funds, which power resides with the Funds' Boards of Trustees. Fidelity carries out the voting of the shares under written guidelines established by the Funds' Boards of Trustees.

•
Pyramis Global Advisors Trust Company ("PGATC"), an indirect wholly-owned subsidiary of FMR LLC and a bank as defined in Section 3(a)(6) of the Exchange Act, is the beneficial owner of 1,670 ordinary shares of Alkermes as a result of its serving as investment manager of institutional accounts owning such shares. Edward C. Johnson 3d and FMR LLC, through its control of Pyramis Global Advisors Trust Company, each has sole dispositive power over 1,670 ordinary shares and sole power to vote or to direct the voting of 1,670 ordinary shares of Alkermes owned by the institutional accounts managed by PGATC as reported above.

(4)
Based solely on a Schedule 13G/A filed February 14, 2012, Wellington Management Company, LLP ("Wellington Management"), in its capacity as investment adviser, may be deemed to beneficially own 17,069,952 ordinary shares of Alkermes which are held of record by clients of Wellington Management. Wellington Management shares voting power over 11,954,121 ordinary shares of Alkermes and shares investment power over 17,069,952 ordinary shares of Alkermes. The number of ordinary shares as to which Wellington Management has the sole power to vote or direct the vote, or dispose or direct the disposition is zero.

44


 SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

        Section 16(a) of the Exchange Act requires the Company's directors and executive officers, and persons who beneficially own more than ten percent of our ordinary shares, to file with the Securities and Exchange Commission initial reports of ownership and reports of changes in ownership of our ordinary shares.

        Executive officers, directors and greater than ten percent shareholders are required by Securities and Exchange Commission regulations to furnish the Company with copies of all Section 16(a) forms they file. To the Company's knowledge, based solely on review of the copies of such reports furnished to the Company for the fiscal year ended March 31, 2012, all reports were timely filed.

45


 REPORT OF THE COMPENSATION COMMITTEE

        No portion of this compensation committee report shall be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, through any general statement incorporating by reference in its entirety the proxy statement in which this report appears, except to the extent that the Company specifically incorporates this report or a portion of it by reference. In addition, this report shall not be deemed filed under either the Securities Act or the Exchange Act.

        The Compensation Committee of the Board of Directors, which is comprised solely of independent directors within the meaning of applicable rules of Nasdaq, outside directors within the meaning of Section 162 of the Internal Revenue Code of 1986, as amended, and non-employee directors within the meaning of Rule 16b-3 under the Exchange Act, has reviewed and discussed with management the Compensation Discussion and Analysis section of this proxy statement for the fiscal year ended March 31, 2012. In reliance on the reviews and discussions referred to above, the Compensation Committee has approved the Compensation Discussion and Analysis and recommended it to the Board of Directors, and the Board of Directors has approved the Compensation Discussion and Analysis for inclusion in this proxy statement.

Respectfully submitted by the Compensation Committee,

Mark B. Skaletsky (Chair)
Paul J. Mitchell
David W. Anstice

For more information about our Compensation Committee and its charter, you are invited to access the Corporate Governance page of the Investors section of the Company's website, available at: http://investor.alkermes.com.

46


 EXECUTIVE COMPENSATION
COMPENSATION DISCUSSION AND ANALYSIS

        This section discusses our executive compensation policies and arrangements as they relate to the following individuals to whom we refer as our named executive officers for the fiscal year ended March 31, 2012:

        On September 16, 2011, upon the closing of the Business Combination: (i) Mark B. Skaletsky, David W. Anstice and Paul J. Mitchell, all of whom comprised the Compensation Committee of Alkermes, Inc. immediately prior to the Business Combination, were appointed to serve as the members of the Compensation Committee of Alkermes plc; and (ii) Richard F. Pops and James M. Frates who, immediately prior to the Business Combination, served as the principal executive officer and principal financial officer, respectively, of Alkermes, Inc. were appointed to serve as the principal executive officer and principal financial officer, respectively, of Alkermes plc. In addition, with the exception of our President, Shane Cooke, our other named executive officers were the named executive officers of Alkermes, Inc. immediately prior to the Business Combination. Accordingly, for purposes of this Executive Compensation—Compensation Discussion and Analysis, the presentation of full fiscal year information will consist of information with respect to Alkermes plc for the period September 17, 2011 through March 31, 2012 and information with respect to Alkermes, Inc., the predecessor company to Alkermes plc from a U.S. GAAP financial reporting perspective, for the period April 1, 2011 through September 16, 2011. We believe this will provide the most relevant disclosure pertaining to the compensation practices of Alkermes plc. The following discussion should be read together with the compensation tables and related disclosures set forth below.

Introduction and Corporate Governance

        Our Compensation Committee, or the Committee, reviews, oversees and administers our executive compensation programs. The Committee's complete roles and responsibilities are set forth in the written charter adopted by the Board, which is available on the Corporate Governance page of the Investors section of our website, available at: http://investor.alkermes.com. The Board selected the following individuals to serve on the Committee for our 2012 fiscal year: Mark B. Skaletsky (Chair), Paul J. Mitchell and David W. Anstice.

Executive Compensation Philosophy and Objectives

        Our executive compensation program is designed to attract, retain and motivate experienced and well-qualified executive officers who will promote our research and product development, manufacturing, commercialization and operational efforts. We structure our executive officer compensation packages based on level of job responsibility, internal and external peer comparisons, individual performance, principles of internal fairness and our overall Company performance. The Committee bases its executive compensation programs on the same objectives that guide us in establishing all our compensation programs, which are:

47

Compensation Program Elements

        The compensation program for executive officers consists of the following elements:

        The Committee utilizes these elements of compensation to structure compensation packages for executive officers that can reward both short and long-term performance of the individual and our Company and foster executive retention.

Base Salary

        Base salaries are used to provide a fixed amount of compensation for the executive's regular work. The Committee establishes base salaries that are competitive with comparable companies for each position and level of responsibility to the extent such comparable companies and positions exist. The salaries of the executive officers are reviewed on an annual basis, at the time of the mid-fiscal year performance review established by us. In determining increases, if any, to base salary, the Committee may consider factors such as the individual's performance, level of pay compared to comparable companies for each position and level of responsibility, experience in the position of the individual, cost of living indices, the magnitude of other annual salary increases at our Company, and general progress towards achieving the corporate objectives. Any base salary increase for an executive officer must be established by the Committee.

Cash Performance Pay

        Cash performance pay motivates executive officers to achieve both short-term operational and longer term strategic goals that are aligned with, and supportive of, our long-term Company value. Cash performance pay is awarded by the Committee after the fiscal year-end based on an evaluation of our Company performance and each individual's contribution to this performance during such fiscal year. Performance objectives are established and evaluated by the Committee as outlined below.

        In March 2011, the Committee approved the Alkermes, Inc. Fiscal 2012 Reporting Officer Performance Pay Plan ("Alkermes, Inc. 2012 Performance Plan") and established target performance pay ranges and target performance pay that may be earned for the period April 1, 2011 to March 31, 2012 by our executive officers, including all of our named executive officers. The plan contained the following fiscal year 2012 corporate objectives for our executives:(i) manage relationships with key business partners, (ii) successfully launch VIVITROL® (naltrexone for extended-release injectable suspension) into the opioid indication, (iii) execute on the expanded development of our late stage product portfolio, (iv) rapidly advance our emerging proprietary pipeline, (v) efficiently supply clinical

48

and commercial products, (vi) achieve financial performance against guidance and (vii) respond to changing business conditions. On May 17, 2011, the Committee added the following as the eighth corporate objective for fiscal year 2012: (viii) complete the acquisition of Elan Drug Technologies and develop and begin execution of an integration plan.

        In March 2011, the Committee set the range of the fiscal year 2012 cash performance pay award under the Alkermes, Inc. 2012 Performance Plan for Mr. Pops at between 0% and 150% of base salary, with a target performance pay award of 75% of base salary, and the range of fiscal year 2012 cash performance pay awards under the Plan for participants other than Richard F. Pops at between 0% and 100% of base salary, with a target cash performance pay award of 50% of base salary. The Committee established such performance pay targets and performance pay ranges based generally on comparable market data.

        In July 2011, in anticipation of the close of the Business Combination and the transformation of the Company into a larger, global pharmaceutical company, the Committee commenced an evaluation of its compensation consultant. On July 29, 2011, the Committee engaged Radford, an AON Hewitt Company ("Radford"), as its independent compensation consultant.

        On September 9, 2011, in order to have an operative reporting officer performance pay plan in effect upon completion of the Business Combination, the Committee recommended that the nominee board of Alkermes plc adopt the Fiscal 2012 Alkermes plc Affiliated Company Reporting Officer Performance Pay Plan (the "2012 Performance Plan"), which incorporated the terms of the existing Alkermes, Inc. 2012 Performance Plan and the terms described below. The nominee board of Alkermes plc adopted such plan immediately prior to the consummation of the Business Combination. The 2012 Performance Plan contained the existing fiscal year 2012 corporate objectives.

        On September 9, 2012, the Committee determined that, subsequent to the completion of the Business Combination, the performance pay for fiscal year 2012 for the Alkermes, Inc. executive officers that continue as Alkermes plc executive officers should be determined under the parameters already established by the Committee and those EDT executives who were appointed as executive officers of Alkermes plc, including Mr. Cooke, would be eligible to receive a performance pay award based on a fifteen month performance period from January 1, 2011 to March 31, 2012. This fifteen month performance pay period was designed to comply with applicable Irish law requirements, to provide former EDT executives with amounts accrued for services rendered while employees of Elan, and to facilitate the transition from a calendar year performance period used by EDT to the Company's fiscal year performance period (April 1 to March 31). The fifteen month performance pay award consisted of (i) an amount equal to the performance pay such executive would have been entitled to receive under the calendar year 2011 performance pay plan in which he participated while employed by Elan, prorated for the period January 1, 2011 to the date of the close of the Business Combination, which amount was credited to the working capital account of EDT by Elan in connection with the Business Combination, and (ii) an amount equal to the performance pay determined by the Committee for the period from September 16, 2011, the closing date of the Business Combination, to March 31, 2012. The Committee set the range of fiscal year 2012 cash performance pay for Mr. Cooke under the Alkermes plc 2012 Performance Plan at between 0% and 150% of base salary, with a target performance pay award of 75% of base salary, with such performance pay prorated for the period during fiscal year 2012 in which Mr. Cooke was an employee of the Company.

        On October 5, 2011, the Committee modified the performance pay range and target performance pay for Richard F. Pops under the 2012 Performance Plan to a performance pay range of between 0% and 200% of base salary and a target performance pay of 100% of base salary. The Committee modified the performance pay range and target performance pay for Mr. Pops based on comparable market data that had recently been updated by Radford and upon the recommendation of Radford, in

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order to position Mr. Pops' compensation above the 50th percentile and closer to the 75th percentile of the Company's post-merger peer group.

        Cash performance pay under our 2012 Performance Plan is awarded after the close of the fiscal year based upon the Committee's review of the performance of our Company against our fiscal year corporate objectives, and the individual performance of each executive officer against such corporate objectives. Individual performance of the participants is determined by the Committee in its sole discretion.

Equity Incentives—Stock Options, Restricted Stock Awards and Restricted Stock Unit Awards

        In September 2011, in connection with the Business Combination, the Alkermes, Inc. Amended and Restated 2008 Stock Option and Incentive Plan, which was initially approved by shareholders in October 2008, was restated and adopted as the Alkermes plc Amended and Restated 2008 Stock Option and Incentive Plan. On December 8, 2011, our shareholders approved the Alkermes plc 2011 Stock Option and Incentive Plan.

        The award of stock options (both incentive and non-qualified options), restricted stock unit awards, restricted stock awards, cash-based awards and performance share awards is permitted under the Equity Plans. All of our equity grants are made pursuant to the Equity Plans. As used herein, the term "restricted stock award," unless otherwise specified, will include restricted stock unit awards and restricted stock awards.

        Grants of stock options and restricted stock awards under our Equity Plans are designed to promote long-term retention and stock ownership, and align the interests of executives with those of shareholders, providing our executives with the opportunity to share in the future value they are responsible for creating. Generally, stock options and non-performance-based restricted stock awards vest in equal annual installments over a four-year period. The Committee may, in its discretion, award equity with a different vesting schedule; however, under the Equity Plans, restricted stock awards granted to employees that have a performance-based goal are required to have a restriction period of at least one year, and those with a time-based restriction are required to have at least a three-year restriction period, although vesting can occur incrementally over such three-year period. We had two retirement provisions open to all employees, only one of which (detailed immediately below) contained eligibility criteria that certain of our executive officers have met. If any employee whose age plus years of service equals at least 55 and who has at least 12 years of service with our Company retires, then those stock options granted under our 2008 Plan before May 17, 2010, and under our 1998 Equity Incentive Plan and Amended and Restated 1999 Stock Option Plan (i) after December 9, 2004 and before May 17, 2010 or (ii) before December 9, 2004 with an exercise price less than US$13.69, shall vest and become exercisable in full for a prescribed period of time after retirement, not to exceed the full term of the grant. As of March 31, 2012, Mr. Pops and Mr. Frates were the only named executive officers who met the retirement eligibility criteria reflected in these stock option grants; however, Mr. Pops was not entitled to the benefit of this retirement provision for stock options granted to him for performance during fiscal years 2008, 2009, 2010, 2011 and 2012; this retirement provision did not apply to grants made on or after May 17, 2010. If the retirement criteria have not been met, vested exercisable stock options remain exercisable for up to three months from the recipient's date of termination from service and unvested stock options are forfeited, unless otherwise specifically determined by the Committee. Currently, there are no special retirement provisions associated with restricted stock awards.

        The number of shares underlying options and restricted stock awards granted to each executive officer is generally determined by the Committee based on: the performance of the executives and their contributions to overall performance of our Company; information with regard to stock option grants and restricted stock awards at comparable companies, and generally within the biotechnology industry,

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based upon data provided by the independent compensation consultant (as discussed below); the dollar value of equity awards, as determined using the Black-Scholes option pricing model; consideration of previous equity awards made to such person; and personal knowledge of the Committee members regarding executive stock options and restricted stock awards at comparable companies. Consideration is also given to the impact of stock option and restricted stock awards on our results of operations.

        The Committee selectively utilizes a combination of stock options and restricted stock awards to focus on senior executives and those other key employees, as identified by our Chief Executive Officer in consultation with our human resources department, who are more likely to be motivated by such equity compensation. The Committee believes that using restricted stock awards, in addition to stock option awards, would be more effective in rewarding and retaining key employees and motivating executives to increase shareholder value. In this context, the Committee balances the mix of stock options and restricted stock awards such that senior executives receive a greater proportion of stock options than restricted stock awards, vice presidents receive a more balanced mixture of the two, and we more aggressively utilize restricted stock awards for other of our key employees.

        The Committee set the range of equity compensation for fiscal year 2012 for Richard F. Pops at 0 to 600,000 share units, with each full value award issued under our 2008 Plan and our 2011 Plan, such as the grant of a unit of restricted stock, counted as 2 share units for each ordinary share and 1.8 share units for each ordinary share, respectively, actually subject to the award, and each grant of a stock option issued under our Equity Plans counted as an award of one share unit for each ordinary share actually subject to the award.

Compensation Determinations

Factors Considered in Determining Compensation

        The Committee may consider a number of factors to assist it in determining compensation for our executive officers.

Company Performance

        As discussed previously, the Committee adopted eight corporate objectives for our Company for fiscal year 2012 to measure the performance of our Company and its senior executives during the fiscal year ended March 31, 2012: (i) manage relationships with key business partners, (ii) successfully launch VIVITROL® (naltrexone for extended-release injectable suspension) into the opioid indication, (iii) execute on the expanded development of our late stage product portfolio, (iv) rapidly advance our emerging proprietary pipeline, (v) efficiently supply clinical and commercial products, (vi) achieve financial performance against guidance, (vii) complete the acquisition of Elan Drug Technologies and develop and begin execution of an integration plan, and (viii) respond to changing business conditions.

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Corporate Objectives
  Accomplishments
Manage relationships with key business partners   We collaborated with our partner, Amylin Pharmaceuticals, Inc. ("Amylin") to respond to a Complete Response Letter ("CRL") from the U.S. Food and Drug Administration ("FDA") for BYDUREON™ and to ensure that the requirements set forth in the CRL were addressed in the reply to the CRL. The FDA subsequently approved BYDUREON for commercial sale in the U.S. in January 2012. Next generation enhancements for BYDUREON, including new once weekly and once monthly product candidates, are being developed.

 
 
We continued our close collaboration with Ortho-McNeil-Janssen Pharmaceuticals, Inc. and Janssen Pharmaceutica International, a division of Cilag International AG ("Janssen") regarding RISPERDAL CONSTA development, manufacture and intellectual property protection, which expanded to include INVEGA®SUSTENNA® following the Business Combination with EDT.

 
 
We coordinated with multiple new partner companies following the Business Combination with EDT, including Acorda Pharmaceuticals, Inc. ("Acorda") and Zogenix, Inc. ("Zogenix"), to effectively integrate those programs into our business.

 
 
We worked with Zogenix to prepare a New Drug Application for ZOHYDRO™ for submission to the FDA; the submission triggered a milestone payment to the Company of $1 million.

Successfully launch VIVITROL into the opioid indication
 
We successfully grew net sales of VIVITROL from $28.9 million for fiscal 2011 to $41.2 million for fiscal 2012 and met our sales guidance for the product, posting a year-over-year gain of 42%.

 
 
We presented positive phase 3 VIVITROL data that supported approval of the product for the prevention of relapse to opioid dependence, following opioid detoxification, at the American Society of Addiction Medicine Conference.

 
 
The positive phase 3 study of VIVITROL for the treatment of opioid dependence was published in the top-tier, peer-reviewed journal, The Lancet.

 
 
Data demonstrating the pharmacoeconomic value of VIVITROL were published in a leading healthcare policy journal, The American Journal of Managed Care.

 
 
We initiated an open-label pilot study of VIVITROL to evaluate its impact on re-arrest and re-incarceration of criminal offenders with a history of opioid dependence.

 
 
We initiated an open-label registry study of VIVITROL to evaluate its efficacy and safety in a real-world setting of opioid dependent patients.

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Corporate Objectives
  Accomplishments
    Our partner, Cilag GmbH International, a subsidiary of Johnson & Johnson, received approval for VIVITROL in Russia for the prevention of relapse to opioid dependence, following opioid detoxification. We received a milestone payment of $3 million related to this approval.

Execute on the expanded
development of our late-stage
product portfolio and

Rapidly advance our emerging proprietary pipeline
 
ALKS 9070

We successfully completed a phase 1b study of ALKS 9070, a proprietary molecule that is designed to provide patients with once-monthly dosing of a medication that, once in the body, converts into aripiprazole, a molecule that is commercially available under the name ABILIFY®.
After a successful End-of-Phase 2 meeting with the FDA, we advanced ALKS 9070 directly into a phase 3 clinical study of approximately 690 patients with schizophrenia.

 
 
ALKS 5461

 
 
We initiated and completed a successful phase 1/2 clinical study of ALKS 5461, which is the combination of ALKS 33 and buprenorphine and is designed to be a non-addictive opioid modulator for the treatment of major depressive disorder (MDD) in patients who had inadequate response to standard treatment.

 
 
Based on the positive results seen in the phase 1/2 study, we accelerated the initiation of a phase 2 study of ALKS 5461 in patients with MDD and inadequate response to standard treatment.

 
 
In partnership with the National Institute on Drug Abuse, we initiated a phase 1/2 clinical study of ALKS 5461 for the treatment of cocaine dependence.

 
 
Early Stage Pipeline

 
 
We organized a focused discovery capability with expertise in opioid receptor biology and chemistry, medicinal chemistry and biologics, and generated data to move various proprietary drug candidates forward.

Efficiently supply clinical and
commercial products
 
We effectively operated three GMP manufacturing sites in two countries producing over 20 products.

 
 
We shipped approximately 8.4 million vials of RISPERDAL® CONSTA®.

 
 
We shipped approximately 57,000 vials of VIVITROL for the U.S. market and met Cilag GmbH International's demand for VIVITROL for the Russian market.

 
 
We shipped approximately 11.3 million tablets of AMPYRA®/FAMPYRA® since completion of the merger with EDT.

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Corporate Objectives
  Accomplishments
    We shipped approximately 288 million doses of our non-core, legacy commercial products to our collaborative partners since the completion of the merger with EDT.

Achieve financial performance against
guidance
 
We provided total revenue guidance of $350 million to $380 million. In February 2012, we increased our expectations for total revenue to $370 million to $400 million. Fiscal 2012 revenues were more than $390 million, an increase of approximately 109% year-over-year, reflecting the financially transformative nature of the merger with EDT.

 
 
In November 2011, we provided Adjusted EBITDA guidance of $45 million to $55 million. In February 2012, we increased our expectations for Adjusted EBITDA to $65 million to $75 million. We reported Adjusted EBITDA for fiscal 2012 of more than $70 million.

 
 
In November 2011, we provided operating expense guidance totaling a range of $410 million to $445 million. Operating expenses for fiscal 2012 were $478.3 million, which included a one-time, non-cash charge of $45.8 million related to the write-off of in-process research and development (IPR&D) intangible assets.

 
 
We provided net sales guidance for VIVITROL of $40 million to $50 million for fiscal 2012. Net sales for VIVITROL were $41.2 million for fiscal 2012, representing a 42% increase year-over-year.

Complete the acquisition of Elan
Drug Technologies and develop and
begin execution of an integration plan
 
We initiated comprehensive integration planning activities following the announcement of our entry into a definitive merger agreement relating to the EDT acquisition in May 2011.

 
 
On September 8, 2011, we held a special shareholder meeting and vote on the merger between Alkermes, Inc. and EDT during which 99.9% of the votes cast were in favor of the merger.

 
 
On September 16, 2011, we announced the completion of the merger and began full execution of the integration plan.

 
 
On December 8, 2012, our shareholders overwhelmingly approved the Alkermes plc 2011 Stock Option and Incentive Plan.

Respond to changing business conditions
 
In May 2011, we entered into a Business Combination Agreement and Plan of Merger with Elan to acquire EDT.
We secured $450 million in term loans to finance the transaction.

 
 
On September 16, 2011 Alkermes, Inc. and EDT merged to form Alkermes plc.

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Corporate Objectives
  Accomplishments
    In March 2012, we initiated and completed an underwritten public offering of 24,150,000 ordinary shares held by a subsidiary of Elan at a price to the public of $16.50 per share. This offering represented more than 75% of the shares held by the Elan subsidiary.

        The Committee does not apply a formula or assign these performance objectives relative weights. Rather, it makes a subjective determination after considering such measures individually and in the aggregate.

Individual Performance

        In establishing compensation levels, the Committee also evaluates each executive's individual performance using certain subjective criteria, including an evaluation of each executive's managerial ability and contribution to achievement of the corporate objectives and to overall corporate performance. In making its evaluations, the Committee consults on an informal basis with other members of the Board. In establishing compensation for executive officers other than Mr. Pops, the Committee reviewed in detail the recommendations of Mr. Pops. With respect to Mr. Pops, the Committee met at the end of the fiscal year to evaluate his performance against the corporate objectives of our Company.

Use of Compensation Consultant for Benchmarking

        Another factor considered by the Committee in determining executive compensation is the high demand for well-qualified personnel. Given such demand, the Committee strives to maintain compensation levels which are competitive with the compensation of other executives in the industry. To that end, the Committee, through our Human Resource Department's Director of Compensation and Benefits, retained the services of Pearl Meyer and Partners ("PMP") through July 28, 2011 and Radford as of July 29, 2011. PMP and Radford are recognized, independent executive compensation consulting firms. The Committee transitioned to Radford because of its expertise in international compensation matters. The Committee engaged PMP and Radford to review market data and various incentive programs and to provide assistance in establishing our cash and equity based compensation targets and awards based, in large part, upon a peer group identification and assessment that it was retained to conduct. PMP and Radford took direction from, and provided reports to, our Director of Compensation and Benefits, who acted on behalf of and at the direction of the Committee. PMP and Radford did not provide us with any services other than the services requested by the Committee.

        In setting the performance pay targets and performance pay ranges for the executives prior to the beginning of the fiscal year, the companies that PMP determined comprised our pharmaceutical peer group at that time consisted of: Alnylam Pharmaceuticals, Inc.; AMAG Pharmaceuticals, Inc.; Amylin Pharmaceuticals, Inc.; Auxilium Pharmaceuticals, Inc.; BioMarin Pharmaceutical Inc.; Cubist Pharmaceuticals, Inc.; Enzon Pharmaceuticals, Inc.; Isis Pharmaceuticals, Inc.; The Medicines Company; Nektar Therapeutics; United Therapeutics Corporation; Vertex Pharmaceuticals Incorporated; and ViroPharma Incorporated. These thirteen publicly traded, United States-headquartered companies competed in similar product, service and labor markets as us and had generally similar revenues to us, in each case prior to the Business Combination.

        PMP also reviewed, and provided to the Committee, data from a survey group of companies, which reflected a broader group of biopharmaceutical/biotechnology companies employing the appropriate revenue, industry and executive role perspectives, and industry composite data, reflecting the average of the industry peer group data and the survey group data, which was calculated for

55

executive compensation comparison purposes. Data for the survey group is collected from survey sources containing data on companies of similar size and in the same industry as us.

        Given the change in size and revenues of the Company following the completion of the Business Combination, Radford conducted a peer group analysis for the Company in September 2011. The companies that Radford determined comprised our pharmaceutical peer group at that time consisted of: Alexion Pharmaceuticals, Inc.; Amylin Pharmaceuticals, Inc.; Auxilium Pharmaceuticals, Inc.; BioMarin Pharmaceutical Inc.; Cubist Pharmaceuticals, Inc.; Dendreon Corporation; Elan Corporation, plc; Endo Pharmaceuticals Holdings Inc.; Human Genome Sciences, Inc.; Incyte Corporation; Jazz Pharmaceuticals plc; Onyx Pharmaceuticals Inc.; Regeneron Pharmaceuticals Inc; Salix Pharmaceuticals Ltd.; The Medicines Company; United Therapeutics Corporation; Vertex Pharmaceuticals Incorporated; and ViroPharma Incorporated. These eighteen publicly traded companies compete in similar product, service and labor markets as us and have generally similar revenues, in each case subsequent to the Business Combination.

        Radford also reviewed, and provided to the Committee, data from a survey group of companies, which reflected a broader group of biopharmaceutical/biotechnology companies employing the appropriate revenue, industry and executive role perspectives. Data is collected from survey sources, including the 2011 Radford Global Life Sciences Survey, containing data on companies of similar size and in the same industry as us. Radford applies a proprietary methodology to the peer group data, survey data and related proxy data to construct a benchmark for compensation comparison purposes.

        The peer group analyses enable the Committee to compare our executive compensation program as a whole and also the pay of individual executives if the jobs are sufficiently similar to make the comparison meaningful. The Committee seeks to ensure that our executive compensation program is competitive, meaning generally between the 50th and the 75th percentile of our peers in terms of value when we achieve targeted performance levels; however, as mentioned elsewhere in our compensation discussion and analysis, the comparative data provided by the Committee's compensation consultant is only one of many factors that the Committee takes into consideration in determining executive and individual compensation programs. The Committee, in its sole authority, has the right to hire or terminate outside compensation consultants.

Executive Officer Compensation Determination

Base Salary

        In October 2011, coinciding with our mid-fiscal year performance review, the Committee reviewed base salaries for all of our executive officers, other than Mr. Cooke whose base salary was determined in connection with the completion of the Business Combination when he became an executive officer of the Company. In determining base salary adjustments for such executive officers for fiscal year 2012, the Committee considered a number of factors, such as cost of living indices, market data for comparable companies, general progress towards achieving the fiscal year corporate objectives and, for those executive officers other than Mr. Pops, the recommendations of Mr. Pops. Based on this review, the Committee increased the base salary of Messrs. Pugh and Frates by approximately 3.5% to $430,000 and $438,500, respectively, and Dr. Ehrich by approximately 4.5% to $430,000.

        Radford noted that Mr. Pops' target performance pay was below the 50th percentile of our peer group. Based on the recommendation of Radford, the Committee increased Mr. Pops' base salary to $800,000, an increase of approximately 12.8%.

        At the time of the Business Combination, the Committee had determined that Mr. Cooke's base salary upon joining the Company would be €444,500, the same as the base salary he had been receiving at Elan prior to the Business Combination. Mr. Cooke's salary was not adjusted as part of the mid-fiscal year performance review, since he had only recently commenced employment with Alkermes.

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Cash Performance Pay

        In April 2012, the Committee reviewed our performance against the fiscal year corporate objectives, the performance of Mr. Pops against such corporate objectives, and the target cash performance pay and cash performance pay range set by the Committee for each executive officer. The Committee determined that the cash performance pay for Mr. Pops for fiscal year 2012 should be equal to US$1.2 million, which is equal to approximately 150% of his base salary. The cash performance pay for Mr. Pops was determined based on the Committee's assessment of his performance against the corporate objectives, including the integral role he played in completing the Business Combination, registering and selling a substantial portion of Elan's equity ownership in the Company, leading the Company's successful integration of EDT, advancing our proprietary pipeline, facilitating FDA approval for BYDUREON, meeting our financial objectives and leading the Company through a transformative period during which the Company had positive one and three year share price appreciation. In setting Mr. Pops' cash performance pay, the Committee also discussed data from Radford regarding cash performance pay for chief executive officers of our peer group companies.

        Also, in April 2012, Mr. Pops presented to the Committee a performance evaluation of each of the other named executive officers and his recommendations for cash performance pay amounts based on such evaluation. Based upon the achievement of our corporate objectives, the challenges faced by each individual named executive officer in achieving those objectives, the individual performance recommendations of Mr. Pops, the target cash performance pay and cash performance pay ranges set by the Committee, and the contribution of each such executive officer towards the successful completion of the Business Combination and subsequent integration activities, specifically noting, in the case of Dr. Ehrich and Mr. Pugh, the valuable role played by each in the development and advancement of the Company's pipeline, the Committee determined and awarded cash performance pay for fiscal year 2012 in an amount equal to, for Messrs. Frates and Pugh and Dr. Ehrich, approximately 67% , 72% and 75%, respectively, of their current base salaries.

        For Mr. Cooke, the Committee determined and awarded performance pay equal to the Euro equivalent of $787,500, which is comprised of (i) €310,674, an amount equal to the performance pay Mr. Cooke was entitled to receive under the calendar year 2011 performance pay plan in which he participated while employed by Elan, which consisted of his target performance pay of 100% of base salary, prorated for the period January 1, 2011 to September 16, 2011 (and which amount was credited to the working capital account of EDT by Elan prior to the completion of the Business Combination); and (ii) an amount equal to approximately 112.5% of his base salary at the Company, prorated to account for the portion of our fiscal year during which Mr. Cooke was employed by the Company.

        All such amounts for our named executive officers are set forth in the Summary Compensation Table below.

Equity Incentives—Stock Options and Restricted Stock Awards

        In May 2012, after the close of fiscal year 2012, the Committee awarded equity grants for fiscal year 2012 performance. In determining the grant of equity to Mr. Pops, the Committee took into consideration comparable peer group data provided by Radford, the dollar value of equity awards, as determined using the Black-Scholes option pricing model, historic awards, the overall equity position of Mr. Pops, the performance of our Company against corporate objectives, and the performance of Mr. Pops against the corporate objectives. The Committee also considered the potential beneficial impact on shareholder return offered by the long-term incentive nature of time-vesting equity grants.

        Based upon these factors, the Committee awarded Mr. Pops a stock option grant of 450,000 ordinary shares and a restricted stock unit award of 32,500ordinary shares. These stock options and restricted stock unit awards vest in four equal annual installments commencing on the one-year

57

anniversary of the grant date, subject to early vesting in certain instances described below in "—Potential Payments upon Termination or Change in Control."

        The following table sets forth equity incentive awards earned by Mr. Pops based on his performance and the performance of our Company during fiscal years 2012 and 2011.

 
   For Fiscal Year 2012 Performance
(April 1, 2011—March 31, 2012) 		  For Fiscal Year 2011 Performance
(April 1, 2010—March 31, 2011)
Richard F. Pops   Stock option grant of 450,000 ordinary shares, granted on May 21, 2012   Stock option grant of 400,000 shares, granted on May 20, 2011

 
 
Restricted stock unit award for 32,500 ordinary shares, granted on May 21, 2012
 
Restricted stock unit award for 32,500 shares, granted on May 20, 2011

        In May 2012, after the close of fiscal year 2012, the Committee awarded equity grants to all other executive officers for performance during such fiscal year. The Committee considered the comparable peer group data provided by Radford, the dollar value of equity awards as determined using the Black-Scholes option pricing model, historic awards, the performance of our Company against corporate objectives, the overall equity position of each of the executives and the recommendations of Mr. Pops based on his assessment of each individual's performance against corporate objectives. Based upon these factors, the Committee awarded the following equity grants to each of Messrs. Frates, Pugh and Cooke, and Dr. Ehrich: a stock option grant of 100,000, 110,000, 160,000 and 120,500 ordinary shares, respectively, and a restricted stock unit award of 15,000, 16,500, 22,500 and 18,000 ordinary shares, respectively. Each of these stock option grants and restricted stock unit awards vests in four equal annual installments commencing on the one-year anniversary of the grant date, subject to early vesting in certain instances such as death or permanent disability and other instances as described below in "—Potential Payments upon Termination or Change in Control."

Stock Ownership Guidelines

        Our Board members and executive officers (consisting of those who are required to file reports under Section 16(a) of the Exchange Act) are subject to stock ownership guidelines. The guidelines are designed to align the interests of our Board members and executive officers with those of our shareholders by ensuring that our Board members and executive officers have a meaningful financial stake in our long-term success. The guidelines establish minimum ownership levels by position (set forth below), with such values determined based on the value of our ordinary shares owned by such persons as of certain annual measurement dates specified in guidelines. Our stock ownership guidelines, which were approved by the Committee and the Alkermes Board in September 2011, continue the minimum ownership levels that the Committee and Board of Directors of Alkermes, Inc. adopted in March 2009. The first measurement date to determine compliance with the ownership levels specified in the prior Alkermes, Inc. guidelines for the Chief Executive Officer (Mr. Pops) was April 1, 2010. Subsequent to the Business Combination, the first measurement date to determine compliance with the ownership levels specified in the guidelines for our Chief Executive Officer is April 1, 2012 and for all other current members of our Board and current executive officers who were employed by Alkermes, Inc. as of April 1, 2010 is April 1, 2015. For Shane Cooke, who became an executive officer after April 1, 2010, and for all future Board members and executive officers these stock ownership

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guidelines will become effective beginning on the April 1 that is five full years after their appointment as a Board member or executive officer.

Position
  Value of Shares Owned
Chief Executive Officer   3.0 times base salary as of April 1, 2012
5.0 times base salary as of April 1, 2015

Board Members
 
US$100,000

Other Executive Officers
 
1.0 times base salary

        All shares directly or beneficially owned by the director or executive officer, including the value of vested stock options (where the market price of our ordinary shares as of the measurement date exceeds the strike price of such option), are included for purposes of determining the value of shares owned under our stock ownership guidelines. Mr. Pops satisfied the ownership levels specified in the guidelines, for Alkermes, Inc., as of April 1, 2010 and April 1, 2011 and, for Alkermes plc, as of April 1, 2012.

Perquisites

        Our President receives a car allowance. The Committee periodically reviews perquisites to assure that they are appropriate in light of our total compensation program and market practice.

Retirement Benefits

        The terms of our 401(k) Savings Plan ("401k Plan") provide for broad-based participation by our executive officers and employees resident in the United States. Under the 401k Plan, all of our employees are eligible to receive matching contributions from us. Our matching contribution for the 401k Plan for fiscal year 2012 was as follows: dollar for dollar on the first 1% of each participant's eligible compensation and US$0.50 on the dollar on the next 5% of each participant's eligible compensation, for a total match of 3.5% of such participant's eligible compensation, subject to applicable federal limits.

        Mr. Cooke, who is resident in Ireland, participates in a private pension plan to which we have agreed to contribute, on an annual basis, an amount equal to 24.45% of his basic payroll salary, paid quarterly.

Other Benefits

        Executive officers are eligible to participate in our employee benefit plans on the same terms as all other employees. These plans include medical, dental and life insurance. We may also provide relocation expense reimbursement, which is negotiated on an individual basis with executive officers. In addition, executive officers are eligible to receive severance benefits in connection with a termination or a change in control as set forth in each of their employment contracts and described more fully below.

Post Termination Compensation and Benefits

        We have a program in place under which our executive officers receive severance benefits if they are terminated without cause or if they terminate their employment for "good reason" (e.g., a material diminution in his or her responsibilities, authority, powers, functions, duties or compensation or a material change in the geographic location at which he or she must perform his or her employment), and thereafter sign a general release of claims. Additionally, named executive officers receive severance benefits if, for a period of time following a corporate transaction or a change in control, they are terminated without cause or they terminate for "good reason." The terms of these arrangements and the amounts payable under them are described in more detail below under "—Potential Payments Upon

59

Termination or Change in Control." We provide these arrangements because we believe that some severance arrangements are necessary in a competitive market for talent to attract and retain high quality executives. In addition, the change in control benefit allows the executives to maintain their focus on our business during a period when they otherwise might be distracted.

        In connection with the Business Combination and Mr. Cooke's transfer of employment from Elan to the Company, Elan and Mr. Cooke agreed on September 16, 2011 that, if his employment with the Company is terminated otherwise than for disciplinary reasons, and the date of expiry of notice of his termination of employment is not later than August 15, 2012, Elan will make up the shortfall, if any, between the severance amount payable to him by the Company, and the amount that he would have received under the existing Elan severance plan had his employment continued and been terminated by Elan.

Tax Deductibility of Compensation

        In general, under Section 162(m) of the Code, we cannot deduct, for federal income tax purposes, compensation in excess of US$1,000,000 paid to our named executive officers. This deduction limitation does not apply, however, to certain "performance-based compensation" within the meaning of Section 162(m) of the Code and the regulations promulgated thereunder.

        Management regularly reviews the provisions of our plans and programs, monitors legal developments and works with the Committee to preserve Section 162(m) tax deductibility of compensation payments. Changes to preserve tax-deductibility are adopted to the extent reasonably practicable, consistent with our compensation policies and as determined to be in our best interests and the best interests of our shareholders.

60

Summary Compensation Table for the 2012, 2011 and 2010 Fiscal Years

        The following table presents and summarizes the compensation paid to, or earned by, our named executive officers for the fiscal year ended March 31, 2012, 2011 and 2010.

Name and Principal Position
  Year   Salary
($) 		  Bonus
($) 		  Stock
Awards
($) 		  Option
Awards
($) 		  Non-Equity
Incentive
Plan
Compensation
($) 		  Change in
Pension Value
and
Nonqualified
Deferred
Compensation
Earnings
($) 		  All Other
Compensation
($) 		  Total ($)  
(a)
   (b)
   (c)(2)
   (d)(3)
   (e)(4)
   (f)(5)
   (g)(6)
   (h)
   (i)(7)
   (j)
  

Richard F. Pops

     FY 12     774,954     —     588,413     3,748,915     1,200,000     —     8,575     6,320,857  

Chairman and Chief Executive

     FY 11     694,488     —     381,550     1,920,547     900,000     —     8,575     3,905,160  

Officer(1)

     FY 10     669,012     —     2,516,250     3,483,330     500,000     —     8,575     7,177,167  

James M. Frates

    
FY 12		    
446,196		    
—		    
271,575		    
938,081		    
295,000		    
—		    
8,613		    
1,959,465		  

Senior Vice President and

     FY 11     414,787     —     204,276     712,080     275,000     —     8,713     1,614,856  

Chief Financial Officer

     FY 10     401,943     —     302,925     534,021     204,639     —     8,575     1,452,103  

Shane Cooke, President(1)

    
FY 12		    
319,085		    
—		    
730,000		    
2,534,000		    
378,622		    
—		    
504,000		    
4,465,707		  

Elliot W. Ehrich

    
FY 12		    
435,093		    
—		    
271,575		    
938,081		    
322,500		    
—		    
8,575		    
1,975,824		  

Senior Vice President, Research

     FY 11     402,817     7,326     196,058     684,306     300,000     —     8,575     1,599,082  

and Development and Chief

     FY 10     390,328     —     256,875     485,907     198,726     —     8,575     1,340,411  

Medical Officer

                                                        

Gordon G. Pugh

    
FY 12		    
437,493		    
—		    
271,575		    
938,081		    
310,000		    
—		    
8,575		    
1,965,724		  

Senior Vice President, Chief

     FY 11     406,646     —     153,794     538,935     300,000     —     8,575     1,407,950  

Operating Officer and Chief

     FY 10     394,045     —     210,825     437,793     200,619     —     8,575     1,251,857  

Risk Officer

                                                        

Notes to Summary Compensation Table

(1)
During the fiscal year ended March 31, 2010, Mr. Pops was appointed Chairman, President and Chief Executive Officer of Alkermes, Inc. On September 16, 2011 (the effective date of the Business Combination), Mr. Pops was appointed Chairman and Chief Executive Officer of the Company and Mr. Cooke was appointed President of the Company.

(2)
The following salary amounts were earned as employees of Alkermes, Inc. from April 1, 2011 through September 16, 2011 (the effective date of the Business Combination): Mr. Pops, $354,650; Mr. Frates, $211,800; Mr. Pugh, $207,650; and Dr. Ehrich, $205,700. Represents salary earned by Mr. Cooke in the amount of €239,536 from September 17, 2011 through March 31, 2012.

(3)
Column (d) for Dr. Ehrich includes a cash bonus of $7,326, earned in October 2010, in connection with the preparation for and participation in the Psychopharmacologic Drugs Advisory Committee for VIVITROL® (naltrexone for extended-release injectable suspension) for the treatment of opioid dependence. This amount was paid to Dr. Ehrich during the year ended March 31, 2011.

(4)
The amounts in column (e) reflect the aggregate grant date fair value of stock awards granted during the fiscal years ended March 31, 2012, 2011 and 2010, respectively, in accordance with U.S. GAAP. The weighted average grant date fair value of stock awards granted during the fiscal years ended March 31, 2012, 2011 and 2010, respectively, are included in footnote 14 "Share-Based Compensation" to our consolidated financial statements for the fiscal year ended March 31, 2012 included in our Annual Report on Form 10-K filed with the SEC on May 18, 2012. The reported fair value for performance-based restricted stock unit awards granted to Mr. Pops for the fiscal year ended March 31, 2010 is the same at both the probable and maximum levels of outcome.

(5)
The amounts in column (f) reflect the aggregate grant date fair value of option awards granted during the fiscal years ended March 31, 2012, 2011 and 2010, respectively, in accordance with U.S. GAAP. Assumptions used in the calculation of the fair value of option awards granted by us in the fiscal years ended March 31, 2012, 2011 and 2010, respectively, are included in footnote 2 "Summary of Significant Accounting Policies" to our consolidated financial statements for the fiscal year ended March 31, 2012 included in our Annual Report on Form 10-K filed with the SEC on May 18, 2012.

(6)
The amounts in column (g) reflect the cash awards paid to the named executive officers for services performed in the fiscal years ended March 31, 2012, 2011 and 2010, pursuant to the 2012 Performance Plan, Alkermes Fiscal Year 2011 Reporting

61

(7)
With the exception of Mr. Frates and Mr. Cooke, the amounts in column (i) reflect our match on contributions made by the named executive officers to our 401k plan. Column (i) for Mr. Frates also includes amounts paid under our wellness incentive plan for the years ended March 31, 2012 and 2011. Column (i) for Mr. Cooke includes (a) €310,674 (equivalent to $408,878) earned by Mr. Cooke as an employee of Elan from January 1, 2011 through September 16, 2011, which amount was credited to the working capital account of EDT by Elan prior to the completion of the Business Combination and paid to Mr. Cooke by the Company; (b) €12,933 (equivalent to $17,228) paid by the Company towards his car allowance from September 17, 2011 until March 31, 2012; and (c) €58,475 (equivalent to $77,894) contributed by the Company to a private pension plan in which Mr. Cooke participates. Mr. Cooke was compensated in Euro. For the purposes of this disclosure, we have converted the Euro payments to U.S. Dollars based on the prevailing exchange rate during the time period over which the payments were made.

Grants of Plan-Based Awards—for Fiscal Year Ended March 31, 2012

        The following table presents information on all grants of plan-based awards made in fiscal year 2012 to our named executive officers:

 
    
    
    
    
    
    
    
    
   All Other
Option
Awards:
Number
of
Securities
Options
(#) 		   
    
  
 
    
   Estimated Future Payouts Under Non-Equity Incentive Plan Awards   Estimated Future Payouts Under Equity Incentive Plan Awards   All Other
Stock
Awards:
Number
of Shares
or Units
(#) 		   
   Grant Date
Fair Value
of Stock
and
Option
Awards
($) 		 
 
    
   Exercise or
Base Price
of Option
Awards
($/Sh) 		 
Name
  Grant Date   Threshold
($) 		  Target
($) 		  Maximum
($) 		  Threshold
(#) 		  Target
(#) 		  Maximum
(#) 		 
(a)
   (b)*
   (c)(1)
   (d)(1)
   (e)(1)
   (f)
   (g)
   (h)
   (i)(3)
   (j)(4)
   (k)
   (l)(5)
  

Richard F. Pops

     5/20/2011     —     —     —     —     —     —     32,500     —     —     588,413  

    5/20/2011     —     —     —     —     —     —     —     400,000     18.105     3,748,915  

    N/A     0     800,000     1,600,000     —     —     —     —     —     —     —  

    N/A     —     —     —     0 (2)   —     600,000 (2)   —     —     —     —  

James M. Frates

    
5/20/2011		    
—		    
—		    
—		    
—		    
—		    
—		    
15,000		    
—		    
—		    
271,575		  

    5/20/2011     —     —     —     —     —     —     —     100,000     18.105     938,081  

    N/A     0     219,250     438,500     —     —     —     —     —     —     —  

Shane Cooke

    
10/5/2011		    
—		    
—		    
—		    
—		    
—		    
—		    
50,000		    
—		    
—		    
730,000		  

    10/5/2011     —     —     —     —     —     —     —     350,000     14.60     2,534,000  

    N/A     0     444,656     889,311     —     —     —     —     —     —     —  

Elliot W. Ehrich

    
5/20/2011		    
—		    
—		    
—		    
—		    
—		    
—		    
15,000		    
—		    
—		    
271,575		  

    5/20/2011     —     —     —     —     —     —     —     100,000     18.105     938,081  

    N/A     0     215,000     430,000     —     —     —     —     —     —     —  

Gordon G. Pugh

    
5/20/2011		    
—		    
—		    
—		    
—		    
—		    
—		    
15,000		    
—		    
—		    
271,575		  

    5/20/2011     —     —     —     —     —     —     —     100,000     18.105     938,081  

    N/A     0     215,000     430,000     —     —     —     —     —     —     —  

Notes to Grants of Plan-Based Awards Table

*
In fiscal year 2013, we awarded stock options and restricted stock awards for fiscal year 2012 performance (in May 2012 after the close of the 2012 fiscal year) to Messrs. Pops, Frates, Cooke and Pugh, and to Dr. Ehrich. As such, all of the stock options and the restricted stock awards reflected in this Grants of Plan-Based Awards table granted on May 20, 2011 were for performance by these grantees in the fiscal year ended March 31, 2011. A stock option and restricted stock award for Mr. Cooke was made in October 2011 as a "new hire" grant under his employment agreement with Alkermes. This Grants of Plan-Based Awards table does not include those stock options and restricted stock awards which were granted on May 21, 2012 for performance by grantees in the fiscal year ended March 31, 2012. Such equity grants were as follows: Mr. Pops, 450,000 stock options and 32,500 restricted stock awards; and Messrs. Frates, Cooke, Pugh, and Dr. Ehrich, 100,000, 160,000, 110,000 and 120,500 stock options and 15,000, 22,500, 16,500 and 18,000 restricted stock awards, respectively. The May 21, 2012 stock option grants were each made at an exercise price of $16.55.

(1)
Represents the target cash performance pay range under the 2012 Performance Plan for performance pay awards that may be earned by named executive officers during the performance period April 1, 2011 to March 31, 2012. The target cash performance pay range for Mr. Pops is 0 to 200% of base salary and for Mr. Cooke is 0% to 150% of base salary, with a target cash performance pay of 100% and 75% of base salary in effect at the time of award, respectively. Mr. Cooke's

62

(2)
Represents the target range of the equity award that may be earned by Mr. Pops for performance during the performance period April 1, 2011 to March 31, 2012. The target range for equity compensation awarded for performance during the fiscal year is 0 to 600,000 share units (with each share underlying a stock option counting as a single share unit and each share underlying a stock award counting as either 2 share units or 1.8 share units, depending upon whether such award was granted under our Restated 2008 Plan or 2011 Plan, respectively). See "Executive Compensation—Executive Compensation and Related Information—Compensation Discussion and Analysis—Equity Incentives—Stock Options and Restricted Stock Awards" for a detailed discussion of the equity awards earned by Mr. Pops for performance during fiscal year 2012.

(3)
Represents stock awards granted under the 2008 Plan which vest in four equal annual installments commencing on the first anniversary of the grant date. All stock awards were granted under the 2008 Plan and no dividend equivalents are paid on unvested restricted stock awards.

(4)
Represents stock options granted under the 2008 Plan which vest in four equal annual installments commencing on the first anniversary of the grant date. Certain of the stock options qualify as incentive stock options under Section 422 of the IRS Code.

(5)
Represents the estimated grant date fair value of stock options and restricted stock awards granted to the named executive officers during the fiscal year ended March 31, 2012, calculated using valuation techniques compliant with U.S. GAAP. Assumptions used in the calculation of the fair value of option awards granted by us during the fiscal year ended March 31, 2012, are included in footnote 2 "Summary of Significant Accounting Policies" to our consolidated financial statements for the fiscal year ended March 31, 2012 included in our Annual Report on Form 10-K filed with the SEC on May 18, 2012. There can be no assurance that the stock options will be exercised (in which case no value will be realized by the optionee) or the value realized upon exercise will equal the grant date fair value.

63

Outstanding Equity Awards at 2012 Fiscal Year-End

        The following table presents the equity awards we have made to each of the named executive officers that were outstanding as of March 31, 2012:

 
   Option Awards   Stock Awards  
Name
  Number of
Securities
Underlying
Unexercised
Options (#)
Exercisable 		  Number of
Securities
Underlying
Unexercised
Options (#)
Unexercisable 		  Equity
Incentive
Plan
Awards:
Number of
Securities
Underlying
Unexercised
Unearned
Options (#) 		  Option
Exercise
Price
($) 		  Option
Expiration
Date 		  Number of
Shares or
Units of
Stock
That Have
Not Vested
(#) 		  Market
Value of
Shares or
Units of
Stock That
Have Not
Vested
($) 		  Equity
Incentive
Plan
Awards:
Number of
Unearned
Shares,
Units or
Other
Rights
That Have
Not Vested
(#) 		  Equity
Incentive
Plan
Awards:
Market or
Payout
Value of
Unearned
Shares,
Units or
Other
Rights
That Have
Not Vested
($) 		 
(a)
   (b)(1)
   (c)
   (d)
   (e)
   (f)(2)
   (g)
   (h)(9)
   (i)
   (j)
  

Richard F. Pops

     —     —     —     —     —     4,750 (3)   88,113     —     —  

    —     —     —     —     —     250,000 (5)   4,637,500     —     —  

    —     —     —     —     —     24,375 (6)   452,156     —     —  

    —     —     —     —     —     32,500 (7)   602,875     —     —  

    100,000     —     —     4.77     7/18/2012     —     —     —     —  

    315,000     —     —     7.36     12/12/2012     —     —     —     —  

    166,250     —     —     9.97     4/25/2013     —     —     —     —  

    149,625     —     —     14.57     10/17/2013     —     —     —     —  

    184,125     —     —     12.16     12/10/2013     —     —     —     —  

    150,000     —     —     12.30     7/12/2014     —     —     —     —  

    350,000     —     —     14.90     12/17/2014     —     —     —     —  

    187,500     —     —     18.60     12/9/2015     —     —     —     —  

    93,750     —     —     20.79     5/2/2016     —     —     —     —  

    120,000     —     —     14.38     12/12/2016     —     —     —     —  

    100,000     —     —     15.95     6/1/2017     —     —     —     —  

    50,000     —     —     14.13     11/5/2017     —     —     —     —  

    127,500     42,500     —     12.29     5/27/2018     —     —     —     —  

    110,000     110,000           8.55     5/26/2019     —     —     —     —  

    250,000     250,000     —     9.21     11/18/2019     —     —     —     —  

    81,250     243,750     —     11.74     5/17/2020     —     —     —     —  

    —     400,000     —     18.105     5/20/2021     —     —     —     —  

James M. Frates

     —     —     —     —     —     1,625 (3)   30,144     —     —  

    —     —     —     —     —     4,250 (4)   78,838     —     —  

    —     —     —     —     —     12,500 (5)   231,875     —     —  

    —     —     —     —     —     13,050 (6)   242,078     —     —  

    —     —     —     —     —     15,000 (7)   278,250     —     —  

    12,296     —     —     4.77     7/18/2012     —     —     —     —  

    60,000     —     —     7.36     12/12/2012     —     —     —     —  

    35,000     —     —     9.97     4/25/2013     —     —     —     —  

    31,500     —     —     14.57     10/17/2013     —     —     —     —  

    83,500     —     —     12.16     12/10/2013     —     —     —     —  

    45,000     —     —     12.30     7/12/2014     —     —     —     —  

    105,000     —     —     14.90     12/17/2014     —     —     —     —  

    56,250     —     —     18.60     12/9/2015     —     —     —     —  

    28,125     —     —     20.79     5/2/2016     —     —     —     —  

    40,000     —     —     14.38     12/12/2016     —     —     —     —  

    30,000     —     —     15.95     6/1/2017     —     —     —     —  

    15,000     —     —     14.13     11/5/2017     —     —     —     —  

    37,500     12,500 (10)   —     12.29     5/27/2018     —     —     —     —  

    32,500     32,500 (10)   —     8.55     5/26/2019     —     —     —     —  

    25,000     25,000     —     9.21     11/18/2019     —     —     —     —  

    30,125     90,375     —     11.74     5/17/2020     —     —     —     —  

    —     100,000     —     18.105     5/20/2021     —     —     —     —  

64

 
   Option Awards   Stock Awards  
Name
  Number of
Securities
Underlying
Unexercised
Options (#)
Exercisable 		  Number of
Securities
Underlying
Unexercised
Options (#)
Unexercisable 		  Equity
Incentive
Plan
Awards:
Number of
Securities
Underlying
Unexercised
Unearned
Options (#) 		  Option
Exercise
Price
($) 		  Option
Expiration
Date 		  Number of
Shares or
Units of
Stock
That Have
Not Vested
(#) 		  Market
Value of
Shares or
Units of
Stock That
Have Not
Vested
($) 		  Equity
Incentive
Plan
Awards:
Number of
Unearned
Shares,
Units or
Other
Rights
That Have
Not Vested
(#) 		  Equity
Incentive
Plan
Awards:
Market or
Payout
Value of
Unearned
Shares,
Units or
Other
Rights
That Have
Not Vested
($) 		 
(a)
   (b)(1)
   (c)
   (d)
   (e)
   (f)(2)
   (g)
   (h)(9)
   (i)
   (j)
  

Shane Cooke

     —     —     —     —     —     50,000 (8)   927,500     —     —  

    —     350,000     —     14.60     10/5/2021     —     —     —     —  

Elliot W. Ehrich

     —     —     —     —     —     1,500 (3)   27,825     —     —  

    —     —     —     —     —     4,250 (4)   78,838     —     —  

    —     —     —     —     —     10,000 (5)   185,500     —     —  

    —     —     —     —     —     12,525 (6)   232,339     —     —  

    —     —     —     —     —     15,000 (7)   278,250     —     —  

    27,000     —     —     14.57     10/17/2013     —     —     —     —  

    44,500     —     —     12.16     12/10/2013     —     —     —     —  

    30,000     —     —     12.30     7/12/2014     —     —     —     —  

    71,500     —     —     14.90     12/17/2014     —     —     —     —  

    38,000     —     —     18.60     12/9/2015     —     —     —     —  

    18,750     —     —     20.79     5/2/2016     —     —     —     —  

    20,500     —     —     14.38     12/12/2016     —     —     —     —  

    30,000     —     —     15.95     6/1/2017     —     —     —     —  

    15,000     —     —     14.13     11/5/2017     —     —     —     —  

    33,750     11,250     —     12.29     5/27/2018     —     —     —     —  

    32,500     32,500     —     8.55     5/26/2019     —     —     —     —  

    20,000     20,000     —     9.21     11/18/2019     —     —     —     —  

    28,950     86,850     —     11.74     5/17/2020     —     —     —     —  

    —     100,000     —     18.105     5/20/2021     —     —     —     —  

Gordon G. Pugh

     —     —     —     —     —     1,500 (3)   27,825     —     —  

    —     —     —     —     —     4,250 (4)   78,838     —     —  

    —     —     —     —     —     7,500 (5)   139,125     —     —  

    —     —     —     —     —     9,825 (6)   182,254     —     —  

    —     —     —     —     —     15,000 (7)   278,250     —     —  

    3,850     —     —     9.97     4/25/2013     —     —     —     —  

    30,000     —     —     14.57     10/17/2013     —     —     —     —  

    54,600     —     —     12.16     12/10/2013     —     —     —     —  

    30,000     —     —     12.30     7/12/2014     —     —     —     —  

    70,000     —     —     14.90     12/17/2014     —     —     —     —  

    37,500     —     —     18.60     12/9/2015     —     —     —     —  

    18,750     —     —     20.79     5/2/2016     —     —     —     —  

    20,000     —     —     14.38     12/12/2016     —     —     —     —  

    30,000     —     —     15.95     6/1/2017     —     —     —     —  

    15,000     —     —     14.13     11/5/2017     —     —     —     —  

    33,750     11,250     —     12.29     5/27/2018     —     —     —     —  

    2,500     32,500     —     8.55     5/26/2019     —     —     —     —  

    15,000     15,000     —     9.21     11/18/2019     —     —     —     —  

    22,800     68,400     —     11.74     5/17/2020     —     —     —     —  

    —     100,000     —     18.105     5/20/2021     —     —     —     —  

Notes to Outstanding Equity Awards at 2012 Fiscal Year-end Table

(1)
Grant date of all stock options is ten years prior to the option expiration date (Column (f)). All stock options vest ratably in 25% increments on the first four anniversaries of the grant date.

(2)
Stock options expire ten years from the grant date.

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(3)
Restricted stock awards granted on May 27, 2008 under the 2002 Restricted Stock Award Plan. The restricted stock awards vest in equal amounts on the first, second, third and fourth anniversaries of the grant date and are issued on the vesting date. No dividend equivalents are paid on restricted stock awards. In the event the individual's employment or any other relationship with us is terminated for any reason, unvested restricted stock awards are forfeited on the date of termination.

(4)
Restricted stock awards granted on May 26, 2009 under the 2008 Plan. The restricted stock awards vest in equal amounts on the first, second, third and fourth anniversaries of the grant date and are issued on the vesting date. No dividend equivalents are paid on restricted stock awards. In the event the individual's employment or any other relationship with us is terminated for any reason, restricted stock awards are forfeited on the date of termination.

(5)
Restricted stock awards granted on November 18, 2009 under the 2008 Plan. With the exception of Mr. Pops, the restricted stock awards vest in equal amounts on the first, second, third and fourth anniversaries of the grant date and are issued on the vesting date. The restricted stock awards granted to Mr. Pops vest 50% on the third anniversary of the grant date and 50% on the fourth anniversary of the grant date. No dividend equivalents are paid on restricted stock awards. In the event the individual's employment or any other relationship with us is terminated for any reason, restricted stock awards are forfeited on the date of termination.

(6)
Restricted stock awards granted on May 17, 2010 under the 2008 Plan. The restricted stock awards vest in equal amounts on the first, second, third and fourth anniversaries of the grant date and are issued on the vesting date. No dividend equivalents are paid on restricted stock awards. In the event the individual's employment or any other relationship with us is terminated for any reason, restricted stock awards are forfeited on the date of termination.

(7)
Restricted stock awards granted on May 20, 2011 under the 2008 Plan. The restricted stock awards vest in equal amounts on the first, second, third and fourth anniversaries of the grant date and are issued on the vesting date. No dividend equivalents are paid on restricted stock awards. In the event the individual's employment or any other relationship with us is terminated for any reason, restricted stock awards are forfeited on the date of termination.

(8)
Restricted stock awards granted on October 5, 2011 under the 2008 Plan. The restricted stock awards vest in equal amounts on the first, second, third and fourth anniversaries of the grant date and are issued on the vesting date. No dividend equivalents are paid on restricted stock awards. In the event the individual's employment or any other relationship with us is terminated for any reason, restricted stock awards are forfeited on the date of termination.

(9)
Market value is based on the closing price of our ordinary shares on March 30, 2012 (the last day of trading for the fiscal year ended March 31, 2012) as reported by Nasdaq, which was $18.55.

(10)
Subject to vesting upon retirement in accordance with the following retirement provision: If any employee, including a named executive officer, retires after having met certain of our retirement eligibility criteria, then those stock options granted under our 2008 Plan before May 17, 2010 and under the 1998 Equity Incentive Plan and amended and restated 1999 Stock Option Plan (i) before May 17, 2010 but after December 9, 2004 or (ii) before December 9, 2004 with an exercise price less than $13.69, shall vest and become exercisable in full for a period of five years after retirement, not to exceed the full term of the grant.

Option Exercises and Stock Vested—for Fiscal Year Ended March 31, 2012

        The following table presents information regarding option exercising and vesting of restricted stock awards for each named executive officer during the year ended March 31, 2012:

Name
  Number of
Shares
Acquired on
Exercise (#) 		  Value
Realized on
Exercise ($) 		  Number of
Shares
Acquired on
Vesting (#) 		  Value
Realized on
Vesting ($) 		 
(a)
   (b)
   (c)
   (d)
   (e)
  

Richard F. Pops

     60,000     753,142     55,625     1,041,809  

James M. Frates

     27,704     336,346     21,725     379,325  

Shane Cooke

     —     —     —     —  

Elliot W. Ehrich

     —     —     14,800     250,838  

Gordon G. Pugh

     69,550     697,862     17,650     313,407  

Pension Benefits—for Fiscal Year Ended March 31, 2012

        None of our named executive officers participate in or have account balances in qualified or non-qualified defined benefit plans sponsored by us.

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Nonqualified Deferred Compensation—for Fiscal Year Ended March 31, 2012

        None of our named executive officers participate in or have account balances in qualified or non-qualified defined benefit plans maintained by us.

Potential Payments upon Termination or Change in Control

        If, during the term of the executive officer's employment agreement with us, we terminate such executive officer's employment without cause or such executive officer terminates his employment for "good reason" (e.g., a material diminution in his responsibilities, authority, powers, functions, duties or compensation or a material change in the geographic location at which he or she must perform his employment) and such executive officer thereafter signs a general release of claims, we will provide severance, as follows: to Mr. Pops, over a twenty-four month period, we will pay an amount equal to two times the sum of (i) his current base salary, plus (ii) the average of his annual cash incentive compensation received for the two immediately preceding fiscal years, and will provide for continued participation in our health benefit plans during such twenty-four month period; to Mr. Cooke, over an eighteen month period, we will pay an amount equal to one and one-half times the sum of (i) his current base salary, plus (ii) the average of his annual cash incentive compensation received for the two immediately preceding fiscal years; and to Messrs. Frates and Pugh and Dr. Ehrich, over a twelve month period, we will pay an amount equal to the sum of (i) his current base salary plus (ii) the average of his annual cash incentive compensation received for the two immediately preceding fiscal years, and will provide for continued participation in our health benefit plans during such twelve month period.

        Under the employment agreements with our executive officers, in the event of a change in control, each executive officer would be entitled to continue his employment with us for a period of two years following the change in control. If, during this two-year period, we terminate such executive officer without cause or if such executive officer terminates his employment for "good reason," we shall pay such executive officer a pro rata bonus (based upon the average of the annual bonus for the prior two years) for the year in which the termination occurs. Additionally, he or she will receive a lump sum payment equal to: for Mr. Pops, two times; and for Messrs. Frates, Cooke and Pugh and Dr. Ehrich, one and one-half times, the sum of his then base salary (or the base salary in effect at the time of the change in control, if higher) plus an amount equal to the average of his annual cash incentive compensation received for the two immediately preceding fiscal years. Messrs. Pops, Pugh, Frates and Dr. Ehrich will also be entitled to continued participation in our health benefit plans: for Mr. Pops, for a period of two years following the date of termination, and for Messrs. Frates and Pugh and Dr. Ehrich, for a period of eighteen months following the date of termination. These change in control payments are expressly in lieu of, and supersede, those severance payments and benefits otherwise payable if we terminate such executive officer without cause or if such executive officer terminates his employment for good reason, provided that such termination occurs within two years after the occurrence of the first event constituting a change in control and that such first event occurs during the period of employment of the executive officer. Messrs. Pops, Pugh, Frates and Dr. Ehrich are also entitled to a "gross-up payment" equal to the excise tax imposed upon the severance payments made in the event of a change in control, if any payment or benefit to the executive, whether pursuant to the employment agreement or otherwise, is considered an "excess parachute payment" and subject to an excise tax under the Code. We no longer provide such "gross-up payments" to newly hired employees. As such, Mr. Cooke is not entitled to a "gross-up payment" in the event of a change in control.

        Upon a change in control of our Company, all outstanding stock options issued under our amended and restated 1999 Stock Option Plan and all outstanding stock options and restricted stock unit awards with time-based vesting issued under our Equity Plans become exercisable. Restricted stock awards issued under our 2002 Restricted Stock Award Plan, all awards with conditions and restrictions relating to the attainment of performance goals issued under our Equity Plans, and all other

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outstanding stock options may become vested and nonforfeitable in connection with a change in control in the Committee's discretion. The consummation of the Business Combination on September 16, 2011 was not deemed a change of control for these purposes.

        Except as set forth below, if any employee, including a named executive officer, retires after having met certain of our retirement eligibility criteria, then those stock options granted under our 2008 Plan before May 17, 2010, and under our 1998 Equity Incentive Plan and amended and restated 1999 Stock Option Plan (i) before May 17, 2010 but after December 9, 2004 or (ii) before December 9, 2004 with an exercise price less than US$13.69, shall vest and become exercisable in full for a prescribed period of time after retirement, not to exceed the full term of the grant. As of March 31, 2012, Messrs. Pops and Frates were the only named executive officers who met the retirement eligibility criteria reflected in these stock option grants; however, as previously discussed, Mr. Pops is not entitled to the benefit of this retirement provision for stock options granted to him for performance during fiscal years 2008, 2009, 2010, 2011 and 2012. If the retirement criteria have not been met, vested exercisable stock options remain exercisable for up to three months from the recipient's date of termination from service and unvested stock options are forfeited. In addition, in the event an employee (including a named executive officer) is terminated by reason of death or permanent disability, his stock options shall vest and become exercisable in full for a period of one to three years following termination depending on the date of the stock option grant, not to exceed the full term of the grant.

        The named executive officers are entitled to certain benefits upon death or disability available to all our employees, as described below. Under our flexible benefits program, all of our eligible employees, including the named executive officers, have the ability to purchase long-term disability coverage that will pay up to 60% of base monthly salary, up to US$20,000 per month during disability. In addition, under our flexible benefits program, we provide life insurance coverage for all of our eligible employees, including the named executive officers, equal to two times base salary, with a maximum of US$500,000 in coverage paid by us. In the event of termination due to death or disability, stock options granted prior to November 2000 become exercisable for a one-year period, not to exceed the full term of the grant, and stock options granted after November 2000 become fully vested and exercisable for a three-year period, not to exceed the full term of the grant.

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Potential Post-Termination Payments

        The following table summarizes the potential payments to each named executive officer under various termination events. The table assumes that the event occurred on March 31, 2012, and the calculations use the closing price of our ordinary shares on March 30, 2012 (the last trading day of fiscal year 2012) as reported by Nasdaq, which was US$18.55 per share.

Name and Payment Elements
  Voluntary
Termination or
Retirement 		  Involuntary
Termination
Without Cause
or Voluntary
Termination for
Good Reason
Not Following a
Change in Control 		  Involuntary
Termination
Without Cause
or Voluntary
Termination for
Good Reason
Following a Change
in Control 		 

Richard F. Pops

                    

Cash Compensation:

                    

Severance

   $     $ 3,000,000   $ 3,700,000  

Equity Awards:

                    

Stock Options and awards(1)

     —     —     11,231,519  

Benefits:

                    

Health and Dental Insurance

     —     36,166     36,166  
               

Total

   $ —   $ 3,036,166   $ 14,967,685  
               

James M. Frates

                    

Cash Compensation:

                    

Severance

   $ —   $ 678,320   $ 1,257,299  

Equity Awards:

                    

Stock Options and awards(1)

     403,250     —     2,048,906  

Benefits:

                    

Health and Dental Insurance

     —     17,316     25,974  
               

Total

   $ 403,250   $ 695,636   $ 3,332,179  
               

Shane Cooke

                    

Cash Compensation:

                    

Severance (2)

   $ —   $ 1,535,642   $ 1,974,397  

Equity Awards:

                    

Stock Options and awards(1)

     —     —     2,310,000  

Benefits:

                    

Health and Dental Insurance

     —     —     —  
               

Total

   $ —   $ 1,535,642   $ 4,284,397  
               

Elliot W. Ehrich

                    

Cash Compensation:

                    

Severance

   $ —   $ 679,363   $ 1,268,408  

Equity Awards:

                    

Stock Options and awards(1)

     —     —     1,914,262  

Benefits:

                    

Health and Dental Insurance

     —     18,083     27,125  
               

Total

   $ —   $ 697,446   $ 3,209,795  
               

Gordon G. Pugh

                    

Cash Compensation:

                    

Severance

   $ —   $ 680,309   $ 1,270,774  

Equity Awards:

                    

Stock Options and awards(1)

     —     —     1,645,458  

Benefits:

                    

Health and Dental Insurance

     —     18,083     27,125  
               

Total

   $ —   $ 698,392   $ 2,943,357  
               

Notes to Post-Termination Payments Table

(1)
This amount represents the difference between the exercise price and the market closing price of our ordinary shares on March 30, 2012, which was $18.55 per share, for outstanding unvested stock options that had an exercise

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(2)
Mr. Cooke's severance amount, which is calculated based on his then current salary and bonus amounts, each of which is paid in Euro, has been converted to U.S. Dollar utilizing the average exchange rate for April 2012, which equaled $1.3161 for one Euro.

Risk Assessment of Compensation Policies and Practices

        The Compensation Committee, at the direction of the Board, reviewed our compensation policies and practices and concluded that these policies and practices are not structured to be reasonably likely to have a material adverse effect on the Company. Specifically, our compensation programs contain many features that mitigate the likelihood of inducing excessive risk-taking behavior. These features include:

70


 DIRECTOR COMPENSATION

        On September 16, 2011, upon the closing of the Business Combination: (i) Dr. Alexander Rich and Michael A. Wall resigned as directors of Alkermes, Inc.; and (ii) the board of directors of Alkermes plc was set at eight and each of Geraldine A. Henwood, Floyd E. Bloom, David W. Anstice, Robert A. Breyer, Wendy L. Dixon, Paul J. Mitchell, Richard F. Pops and Mark B. Skaletsky, all of whom were directors of Alkermes, Inc. immediately prior to Business Combination, were appointed as directors of Alkermes plc. Accordingly, the presentation of full fiscal year director compensation information consists of information with respect to Alkermes plc for the period September 17, 2011 through March 31, 2012 and information with respect to Alkermes, Inc., the predecessor company to Alkermes plc from a U.S. GAAP financial reporting perspective, for the period April 1, 2011 through September 16, 2011. We believe this will provide the most relevant disclosure pertaining to the compensation practices of Alkermes plc.

        David W. Anstice, Floyd E. Bloom, Robert A. Breyer, Geraldine A. Henwood, Paul J. Mitchell, Wendy L. Dixon and Mark B. Skaletsky served as non-employee directors for the fiscal year ended March 31, 2012. Alexander Rich served as a non-employee director, and Michael A. Wall as a director, until their resignation from the board of directors on September 16, 2011. During fiscal year 2012, Michael A. Wall also served as a part-time employee of our Company. We believe that we obtain services from Mr. Wall on terms no less favorable to us than those of an independent third party.

        Richard F. Pops became Chairman of the Board effective April 1, 2007 and was an employee during the fiscal year ended March 31, 2012. Mr. Pops does not receive equity or attendance fees for his service on the Board.

Annual retainers

        The Board adopted the following annual retainers, to be paid pro rata on a quarterly basis, for service on the Board and Board committees, and for participation in each telephonic Board meeting.

 
   Retainer Fee  
Service
  April 1, 2011 -
September 16,
2011 		  September 17,
2011 -
December 31,
2011 		  Effective as
of January 1,
2012 		 

Board Member

   $ 30,000   $ 45,000   $ 60,000  

Board Member Meeting Attendance

     2,500     3,500     3,500  

Board Member Telephonic Meeting Attendance

     1,250     —     —  

Audit and Risk Committee Chair

     22,000     25,000     25,000  

Audit and Risk Committee Member

     10,000     15,000     15,000  

Compensation Committee Chair

     15,000     20,000     20,000  

Compensation Committee Member

     7,500     10,000     10,000  

Nominating and Corporate Governance Committee Chair

     10,000     15,000     15,000  

Nominating and Corporate Governance Committee Member

     5,000     7,500     7,500  

        In addition, we reimburse our directors for travel and other necessary business expenses incurred in the performance of their services for us and extend coverage to them under our travel accident and directors' and officers' indemnity insurance policies.

Equity Compensation

        Each of our non-employee directors receive, on the date of our annual general meeting of shareholders, an option to purchase ordinary shares in the amount set forth in the table below. In addition, upon becoming a member of the Board, each new non-employee director automatically receives a one-time grant of options to purchase ordinary shares in an amount set forth in the table below. If a new non-employee director was elected other than at the annual meeting of shareholders,

71

the newly elected non-employee director also received a grant of options equal to the product of the annual director ordinary share grant multiplied by a fraction, the numerator of which equaled the number of months remaining until the next annual meeting of our shareholders and the denominator of which equaled 12. During our fiscal year 2012, as a newly formed company, we did not hold an annual general meeting of shareholders. As a result, on October 5, 2011, the Committee made the annual grant to directors which normally would have occurred automatically on the date of our annual general meeting of shareholders.

 
   Equity Compensation
Service
  April 1, 2011 -
September 16, 2011 		  September 17, 2011 -
March 31, 2012
Initial equity grant upon joining the Board   One-time grant of an option to purchase 20,000 shares of common stock, vesting in full six months after the date of grant   One-time grant of an option to purchase 35,000 ordinary shares, vesting ratably over the three calendar years following the date of grant

Annual equity grant for Board members
 
Option to purchase 20,000 shares of common stock, vesting in full six months after the date of grant
 
Option to purchase 25,000 ordinary shares, vesting in full on the one year anniversary of the date of grant

        Non-employee directors did not receive any options to purchase ordinary shares except for the yearly grant described above and the one-time grant of an option to purchase ordinary shares upon joining the Board.

Fiscal Year 2012 changes to Director Compensation

        On July 29, 2011, the Committee, in anticipation of the closing of the Business Combination, unanimously voted to retain Radford as the Committee's independent compensation consultant and authorized management to terminate the services of PMP. The Committee then engaged Radford to assist in reviewing the compensation of our non-employee directors, including providing the Committee with an updated report and benchmarking analysis of our non-employee director compensation relative to the peer companies of Alkermes.

        On September 9, 2011, Radford presented its analysis of the Alkermes, Inc. Board compensation, which included an assessment of market comparable ranges for board compensation for the Company, given its expected financial and operational composition after consummation of the EDT acquisition. After review and discussion of the Alkermes, Inc. Board compensation analysis and proposed new Alkermes Board compensation, the Committee recommended to the Alkermes, Inc. Board, and on September 12, 2011, the Alkermes, Inc. Board approved, the proposed new Board compensation recommended by Radford. The Board approved such revised compensation on September 16, 2011. In December 2011, Radford, in recognition of the increased time, travel and effort required of our directors after completion of the Business Combination, recommended a modification to the Board annual cash retainer. As a result, the Committee recommended, and the Board approved, an increase in the Board's annual cash retainer, effective January 1, 2012, from $45,000 to $60,000.

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Director Compensation Table—for Fiscal Year Ended March 31, 2012

        The following table presents and summarizes the compensation of our directors for the year ended March 31, 2012.

Name   Fees
Earned or
Paid in
Cash
($) 		  Stock
Awards
($) 		  Option
Awards
($) 		  Non-Equity
Incentive Plan
Compensation
($) 		  Change in
Pension
Value and
NQDC
Earnings
($) 		  All Other
Compensation
($) 		  Total
($) 		 
(a)
   (b)(2)
   (c)
   (d)(3)(4)
   (e)
   (f)
   (g)(5)
   (h)
  

David W. Anstice

     73,000     —     181,750     —     —     —     254,750  

Floyd E. Bloom

     72,250     —     181,750     —     —     —     254,000  

Robert A. Breyer

     66,750     —     181,750     —     —     —     248,500  

Wendy L. Dixon

     69,250     —     181,750     —     —     —     251,000  

Geraldine Henwood

     76,750     —     181,750     —     —     —     258,500  

Paul J. Mitchell

     96,500     —     181,750     —     —     —     278,250  

Alexander Rich (1)

     27,500     —     —     —     —     —     27,500  

Mark B. Skaletsky

     96,750     —     181,750     —     —     —     278,500  

Michael A. Wall* (1)

     25,000     —     —     —     —     39,723     64,723  

Notes to Director Compensation Table—For Fiscal Year Ended March 31, 2012

*
Part-time employee director.

(1)
Dr. Rich and Mr. Wall resigned from the board upon the consummation of the Business Combination on September 16, 2011.

(2)
Represents fees earned by our directors in the fiscal year ended March 31, 2012 for services as a director, including annual retainer fees, committee and/or committee chair fees and meeting fees. Amounts include the following fees paid to directors for their service on the Alkermes, Inc. Board and/or its Committees from April 1, 2011 through September 16, 2011: Mr. Anstice, $25,625; Dr. Bloom, $28,750; Mr. Breyer, $22,500; Dr. Dixon, $25,000; Ms. Henwood, $28,750; Mr. Mitchell, $31,125; Dr. Rich, $27,500; Mr. Skaletsky, $32,500; Mr. Wall, $25,000.

(3)
The amounts in column (d) reflect the aggregate grant date fair value recognized for financial statement reporting purposes, excluding estimates of forfeitures, if any, in accordance with U.S. GAAP for stock option awards granted in the fiscal year ended March 31, 2012. Each director received an option to purchase 25,000 ordinary shares, which had an estimated grant date fair value of $7.27 per share. The stock options granted to the non-employee directors were granted under the Restated 2008 Plan. Stock options granted under the Restated 2008 Plan are nonqualified stock options that vest one year from the grant date and expire upon the earlier of ten years from the grant date or three years after the optionee terminates their service relationship with us. Additionally, any unvested portion of the option grant shall vest upon the optionee's termination of their service relationship with us. We recognize the cost of the stock options granted to non-employee on a straight-line basis over the requisite service period of the stock options. There can be no assurance that the stock options will be exercised or the value realized upon exercise will equal the grant date fair value.

(4)
Assumptions used in the calculation of the fair value of option awards made by us for the stock options granted to directors on October 5, 2011 are as follows: option exercise price, $14.60; expected term, 6.95 years; volatility, 48%; interest rate, 1.45%; dividend yield, zero. Our directors hold the following aggregate number of outstanding stock options as of March 31, 2012: David W. Anstice, 105,000 shares; Floyd E. Bloom, 205,000 shares; Robert A. Breyer, 175,400 shares; Wendy L. Dixon, 60,000 shares; Geraldine A. Henwood, 165,000 shares; Paul J. Mitchell, 213,000 shares; and Mark B. Skaletsky, 184,000 shares.

(5)
Represents fees paid to Mr. Wall for his service as a part-time employee of Alkermes from April 1, 2011 through September 16, 2011, the date he resigned from the Board. We believe that Mr. Wall's part-time employee status is no less favorable to us than obtaining services from an independent third party.

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 CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS

Shareholder's Agreement with Elan

        In connection with the Business Combination, we paid Elan $500 million in cash and issued 31.9 million ordinary shares of Alkermes plc to the Elan Shareholder, a wholly owned subsidiary of Elan. In connection with this share issuance, we entered into a Shareholder's Agreement with Elan and the Elan Shareholder. Under the Shareholder's Agreement, Elan was subject to certain restrictions on its ability to transfer our ordinary shares without our consent. Elan could initially only transfer a portion of its holdings (up to 40.75% (approximately 13 million ordinary shares) of its holdings) in a marketed registered underwritten offering. At least 90 days after such offering, Elan could transfer a further portion of its holdings (up to an additional 31.5% (approximately 10 million ordinary shares) of its holdings) in another marketed registered underwritten offering.

        On March 13, 2012, the Elan Shareholder sold 24,150,000 Shares in a marketed underwritten registered offering (the "Registered Offering") (including 3,150,000 Shares sold pursuant to the full exercise of an option to purchase such amount of Shares granted to the underwriters pursuant to the Underwriting Agreement). The Shares were sold in the Registered Offering pursuant to a shelf registration statement on Form S-1 filed by the Company with the SEC in connection with the resale of the Shares by the Elan Shareholder, which the SEC declared effective on March 2, 2012. In connection with this Registered Offering, we executed two Waiver and Consent Letters to the Shareholder's Agreement on March 7, 2012 and March 8, 2012, pursuant to which we (i) agreed to waive the limitations that would prohibit both a transfer of the Shares prior to the six (6) month anniversary of the Closing Date (as defined in the Shareholder's Agreement), and following such date, the transfer of more than 40.75% of the Shares in the Registered Offering and (ii) agreed and consented to the sale of the 24,150,000 Shares by the Elan Shareholder in the Registered Offering.

        Currently, as a holder of less than ten percent (10%) of our ordinary shares outstanding, Elan remains subject to certain restrictions pursuant to the terms of the Shareholder's Agreement, including:

Development and Manufacturing Services Agreement

        On September 16, 2011, we entered into a Development and Manufacturing Services Agreement with Elan, pursuant to which we may perform certain development services in respect of an Elan clinical product, and have the right to manufacture a certain percentage of clinical, registration and, if approved, commercial supplies of such product.

Transition Services Agreement

        On September 16, 2011, we entered into an Agreement for the Provision of Transitional Services with Elan, pursuant to which we purchased and continue to purchase from Elan certain transition

74

services for specified periods of time following the closing of the Business Combination. The services are currently due to terminate on September 30, 2012.

Policy Concerning Related Person Transactions

        Our Audit and Risk Committee charter, which is posted on the Corporate Governance tab of the Investors section of our website, available at http://investor.alkermes.com, makes clear that our Audit and Risk Committee is responsible for reviewing transactions with related persons, including transactions that would be required to be disclosed in this prospectus in accordance with SEC rules. In addition, our Code of Business Conduct and Ethics, which sets forth legal and ethical guidelines for all of our directors and employees, states that directors, executive officers and employees must avoid relationships or activities that might impair that person's ability to make objective and fair decisions while acting in their company roles and requires that, among other things, any transactions with related persons be disclosed to, and receive the approval of, the appropriate committee of our board.

        In addition, at the end of each fiscal quarter, we ask all of our directors and officers (vice presidents and higher) to disclose a list of their "related parties"; this practice is not pursuant to a written policy or procedure. Related parties are defined as any public, private, profit, or non-profit companies or organizations of which they or their immediate family is an officer, director or 10% or greater shareholder. All reported "related parties" are sent to our Finance department, which checks them against transactions of the Company in that prior quarter. At the Audit and Risk Committee meeting held to review the quarter's financial results, any transactions between a reported related party and us are reported to the Audit and Risk Committee for its review and, if deemed appropriate by the Audit and Risk Committee in its sole discretion, approval.


DISCLOSURE WITH RESPECT TO OUR EQUITY COMPENSATION PLANS

Equity Compensation Plan Information

Plan Category
  Number of
Securities to
be Issued
Upon Exercise
of
Outstanding
Options,
Warrants and
Rights(1) 		  Weighted
Average
Exercise Price
of
Outstanding
Options,
Warrants and
Rights(2) 		  Number of
Securities
Remaining
Available for
Future
Issuance(1) 		 

Equity compensation plans approved by security holders

     17,359,760   $ 13.68     9,381,849  
(1)
Share information is as of March 31, 2012. There are no warrants or other rights outstanding. In addition, as of March 31, 2012, there are 2,114,176 ordinary shares issued as restricted stock awards, which are subject to forfeiture until such awards have vested. These restricted stock awards are not included in this share number.

(2)
Represents the weighted average exercise price of our outstanding options under our equity compensation plans. This does not include outstanding restricted stock awards under our equity compensation plans as such awards do not have an exercise price.

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 OTHER BUSINESS

        The Board of Directors does not intend to present to the Annual General Meeting of Shareholders any business other than that set forth in this proxy statement. If any other matter is presented to the Annual General Meeting which under applicable proxy regulations need not be included in this proxy statement or which the Board of Directors did not know a reasonable time before this solicitation would be presented, the persons named in the accompanying proxy will have discretionary authority to vote proxies with respect to such matter in accordance with their best judgment.

Independent Auditor

        PwC, our independent auditor, audited the consolidated financial statements of the Company for the fiscal year ended March 31, 2012. Representatives of PwC are expected to attend the Annual General Meeting, will have the opportunity to make a statement if they desire to do so and are expected to be available to respond to appropriate questions.

Shareholder Proposals for the 2013 Annual General Meeting

        In accordance with the rules established by the SEC, as well as under the provisions of our Articles of Association, any shareholder proposal submitted pursuant to Rule 14a-8 under the Exchange Act intended for inclusion in the Proxy Statement for next year's Annual General Meeting must be received by us no earlier than January 21, 2013 and no later than March 22, 2013. Such proposals should be sent to our Secretary at Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland. To be included in the Proxy Statement, the proposal must comply with the requirements as to form and substance established by the SEC and our Articles of Association and must be a proper subject for shareholder action under Irish law.

Expenses and Solicitation

        The cost of solicitation will be borne by Alkermes, and in addition to directly soliciting shareholders by mail, Alkermes may request banks and brokers to solicit their customers who have stock of Alkermes registered in the name of the nominee and, if so, will reimburse such banks and brokers for their reasonable out-of-pocket costs. Solicitation by officers and employees of Alkermes may also be made of some shareholders in person or by mail or telephone following the original solicitation. In addition, Alkermes has retained the services of Alliance Advisors LLC to solicit proxies, at an estimated cost of $8,000 plus such firm's expenses.

Presentation of Irish Statutory Accounts

        The Company's Irish Statutory Accounts for the fiscal year ended March 31, 2012, including the reports of the auditors thereon, will be presented at the Annual General Meeting. There is no requirement under Irish law that such statements be approved by shareholders, and no such approval will be sought at the Annual General Meeting. The Company's Irish Statutory Accounts are available with the Proxy Materials at www.edocumentview.com/alks.

Registered and Principal Executive Offices

        The registered and principal executive offices of Alkermes plc are located at Connaught House, 1 Burlington Road, Dublin 4, Ireland. The telephone number there is +353 1 772-8000.

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United States Securities and Exchange Commission Reports

        Copies of our Annual Report on Form 10-K for the fiscal year ended March 31, 2012, as filed with the SEC, are available to shareholders free of charge under the "Investors" tab of our website at www.alkermes.com or by writing to our Secretary at Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland, Attention: Company Secretary.

Delivery of Documents to Shareholders Sharing an Address

        If you have requested a paper copy of our proxy materials, our Annual Report, including our audited financial statements for the year ended March 31, 2012, is being mailed to you along with this Proxy Statement. In order to reduce printing and postage costs, only one Annual Report and one Proxy Statement will be mailed to multiple shareholders sharing an address unless the Company receives contrary instructions from one or more of the shareholders sharing an address. If your household has received only one Annual Report and one Proxy Statement, the Company will deliver promptly a separate copy of such documents to any shareholder who sends a written request to Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland, Attention: Company Secretary. If your household is receiving multiple copies of the Company's annual reports or proxy statements and you wish to request delivery of a single copy, you may send a written request to Alkermes plc, Connaught House, 1 Burlington Road, Dublin 4, Ireland, Attention: Company Secretary.

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 APPENDIX A


ALKERMES plc

2011 Stock Option and Incentive Plan

SECTION 1.    GENERAL PURPOSE OF THE PLAN; DEFINITIONS    

        The name of the plan is the Alkermes plc 2011 Stock Option and Incentive Plan (the "Plan"). The Plan is established in connection with a business combination transaction pursuant to which Alkermes, Inc. (the "Company") would become a wholly owned subsidiary of a new holding company to be named Alkermes plc, an Irish public limited company (the "Parent"). The purpose of the Plan is to encourage and enable the officers, employees, Non-Employee Directors and other key persons (including consultants and prospective employees) of the Parent and its Subsidiaries upon whose judgment, initiative and efforts the Parent and its Subsidiaries largely depend for the successful conduct of their business to acquire a proprietary interest in the Parent. It is anticipated that providing such persons with a direct stake in the Parent's welfare will assure a closer identification of their interests with those of the Parent and its stockholders, thereby stimulating their efforts on the Parent's and its Subsidiaries' behalf and strengthening their desire to remain with the Parent and its Subsidiaries.

        The following terms shall be defined as set forth below:

        "Act" means the Securities Act of 1933, as amended, and the rules and regulations thereunder.

        "Administrator" means the compensation committee of the Board or a similar committee performing the functions of the compensation committee and which is comprised of not less than two Non-Employee Directors who are independent.

        "Award" or "Awards," except where referring to a particular category of grant under the Plan, shall include Incentive Stock Options, Non-Qualified Stock Options, Restricted Stock Awards, Restricted Stock Unit Awards, Cash-Based Awards and Performance Share Awards.

        "Award Certificate" means a written or electronic certificate setting forth the terms and provisions applicable to an Award granted under the Plan. Each Award Certificate is subject to the terms and conditions of the Plan.

        "Board" means the Board of Directors of the Parent.

        "Cash-Based Award" means an Award entitling the recipient to receive a cash-denominated payment.

        "Code" means the Internal Revenue Code of 1986, as amended, and any successor Code, and related rules, regulations and interpretations.

        "Covered Employee" means an employee who is a "Covered Employee" within the meaning of Section 162(m) of the Code.

        "Effective Date" means the date set forth in Section 18.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended, and the rules and regulations thereunder.

        "Fair Market Value" of the Stock on any given date for purposes of the Plan, unless otherwise required by any applicable provision of the Code or any regulations issued thereunder, means the fair market value of the Stock determined in good faith by the Administrator; provided, however, that if the Stock is admitted to quotation on the National Association of Securities Dealers Automated Quotation System ("NASDAQ"), NASDAQ Global Market or another national securities exchange, the determination shall be made by reference to the closing price reported by NASDAQ or such other

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exchange. If the market is closed on such date, the determination shall be made by reference to the last date preceding such date for which the market is open.

        "Incentive Stock Option" means any Stock Option designated and qualified as an "incentive stock option" as defined in Section 422 of the Code.

        "Non-Employee Director" means a member of the Board who is not also an employee of the Parent or any Subsidiary.

        "Non-Qualified Stock Option" means any Stock Option that is not an Incentive Stock Option.

        "Option" or "Stock Option" means any option to purchase shares of Stock granted pursuant to Section 5.

        "Performance-Based Award" means any Restricted Stock Award, Restricted Stock Unit Award, Performance Share Award or Cash-Based Award granted to a Covered Employee that is intended to qualify as "performance-based compensation" under Section 162(m) of the Code and the regulations promulgated thereunder.

        "Performance Criteria" means the criteria that the Administrator selects for purposes of establishing the Performance Goal or Performance Goals for an individual for a Performance Cycle. The Performance Criteria (which shall be applicable to the organizational level specified by the Administrator, including, but not limited to, the Parent or a unit, division, group, or a Subsidiary) that will be used to establish Performance Goals are limited to the following: earnings before interest, taxes, depreciation and amortization, net income (loss) (either before or after interest, taxes, depreciation and/or amortization), changes in the market price of the Stock, economic value-added, initiation or completion of clinical trials, results of clinical trials, drug development or commercialization milestones, collaboration milestones, operational measures including production capacity and capability, hiring and retention of key managers, expense management, capital raising transactions, sales or revenue, acquisitions or strategic transactions, operating income (loss), cash flow (including, but not limited to, operating cash flow and free cash flow), return on capital, assets, equity, or investment, stockholder returns, gross or net profit levels, operating margins, earnings (loss) per share of Stock and sales or market shares, any of which may be measured either in absolute terms or as compared to any incremental increase or as compared to results of a peer group.

        "Performance Cycle" means one or more periods of time, which may be of varying and overlapping durations, as the Administrator may select, over which the attainment of one or more Performance Criteria will be measured for the purpose of determining a grantee's right to and the payment of a Restricted Stock Award, Restricted Stock Unit Award, Performance Share Award or Cash-Based Award. Each such period shall not be less than 12 months.

        "Performance Goals" means the specific goals established in writing by the Administrator for a Performance Cycle based upon the Performance Criteria.

        "Performance Share Award" means an Award entitling the recipient to acquire shares of Stock upon the attainment of specified Performance Goals.

        "Restricted Stock Award" means an Award entitling the recipient to acquire, at such purchase price (which may be zero) as determined by the Administrator, shares of Stock subject to such restrictions and conditions as the Administrator may determine at the time of grant.

        "Restricted Stock Unit Award" means an Award of phantom stock units to a grantee.

        "Sale Event" shall mean (i) the sale of all or substantially all of the assets of the Parent on a consolidated basis to an unrelated person or entity, (ii) a merger, reorganization or consolidation in which the outstanding shares of Stock are converted into or exchanged for securities of the successor entity and the holders of the Parent's outstanding voting power immediately prior to such transaction

A-2

do not own a majority of the outstanding voting power of the successor entity immediately upon completion of such transaction, or (iii) the sale of all of the Stock to an unrelated person or entity.

        "Sale Price" means the value as determined by the Administrator of the consideration payable, or otherwise to be received by stockholders, per share of Stock pursuant to a Sale Event.

        "Section 409A" means Section 409A of the Code and the regulations and other guidance promulgated thereunder.

        "Stock" means the Common Stock, par value $.01 per share, of Parent, subject to adjustments pursuant to Section 3.

        "Subsidiary" means the Company and any corporation or other entity in which the Parent has at least a 50 percent interest, either directly or indirectly.

        "Ten Percent Owner" means an employee who owns or is deemed to own (by reason of the attribution rules of Section 424(d) of the Code) more than 10 percent of the combined voting power of all classes of stock of the Parent or any parent or subsidiary corporation of the Parent, within the meaning of Section 424 of the Code.

SECTION 2.    ADMINISTRATION OF PLAN; ADMINISTRATOR AUTHORITY TO SELECT GRANTEES AND DETERMINE AWARDS    

        (a)    Administration of Plan.    The Plan shall be administered by the Administrator.

        (b)    Powers of Administrator.    The Administrator shall have the power and authority to grant Awards consistent with the terms of the Plan, including the power and authority:

        All decisions and interpretations of the Administrator shall be binding on all persons, including the Parent, Subsidiaries and Plan grantees.

A-3

        (c)    Delegation of Authority to Grant Options.    Subject to applicable law, the Administrator, in its discretion, may delegate to a subcommittee comprised of one or more members of the Board all or part of the Administrator's authority and duties with respect to the granting of Options to employees who are not subject to the reporting and other provisions of Section 16 of the Exchange Act. Any such delegation by the Administrator shall include a limitation as to the amount of Options that may be granted during the period of the delegation and shall contain guidelines as to the determination of the exercise price and the vesting criteria. The Administrator may revoke or amend the terms of a delegation at any time but such action shall not invalidate any prior actions of the Administrator's delegate or delegates that were consistent with the terms of the Plan.

        (d)    Award Certificates.    Awards under the Plan shall be evidenced by Award Certificates that set forth the terms, conditions and limitations for each Award which may include, without limitation, the term of an Award and the provisions applicable in the event employment or service terminates.

        (e)    Indemnification.    Subject to Section 200 of the Irish Companies Act 1963, neither the Board nor the Administrator, nor any member of either or any delegate thereof, shall be liable for any act, omission, interpretation, construction or determination made in good faith in connection with the Plan, and the members of the Board and the Administrator (and any delegate thereof) shall be entitled in all cases to indemnification and reimbursement by the Parent in respect of any claim, loss, damage or expense (including, without limitation, reasonable attorneys' fees) arising or resulting therefrom to the fullest extent permitted by law and/or under the Parent's articles or bylaws or any directors' and officers' liability insurance coverage which may be in effect from time to time and/or any indemnification agreement between such individual and the Parent.

        (f)    Foreign Award Recipients.    Notwithstanding any provision of the Plan to the contrary, in order to comply with the laws in other countries in which the Parent and its Subsidiaries operate or have employees or other individuals eligible for Awards, the Administrator, in its sole discretion, shall have the power and authority to: (i) determine which Subsidiaries shall be covered by the Plan; (ii) determine which individuals outside the United States are eligible to participate in the Plan; (iii) modify the terms and conditions of any Award granted to individuals outside the United States to comply with applicable foreign laws; (iv) establish subplans and modify exercise procedures and other terms and procedures, to the extent the Administrator determines such actions to be necessary or advisable (and such subplans and/or modifications shall be attached to the Plan as appendices); provided, however, that no such subplans and/or modifications shall increase the share limitations contained in Section 3(a) hereof; and (v) take any action, before or after an Award is made, that the Administrator determines to be necessary or advisable to obtain approval or comply with any local governmental regulatory exemptions or approvals. Notwithstanding the foregoing, the Administrator may not take any actions hereunder, and no Awards shall be granted, that would violate the Exchange Act or any other applicable United States securities law, the Code, or any other applicable United States governing statute or law.

SECTION 3.    STOCK ISSUABLE UNDER THE PLAN; MERGERS; SUBSTITUTION    

        (a)    Stock Issuable.    

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        (b)    Effect of Awards.    The grant of any full value Award (i.e., an Award other than an Option) shall be deemed, for purposes of determining the number of shares of Stock available for issuance under Section 3(a)(i), as an Award of 1.8 shares of Stock for each such share of Stock actually subject to the Award and shall be treated similarly if returned to reserve status when forfeited or canceled as provided in Section 3(a). The grant of an Option shall be deemed, for purposes of determining the number of shares of Stock available for issuance under Section 3(a)(i), as an Award for one share of Stock for each such share of Stock actually subject to the Award.

        (c)    Changes in Stock.    Subject to Section 3(d) hereof, if, as a result of any reorganization, recapitalization, reclassification, stock dividend, stock split, reverse stock split or other similar change in the Parent's capital stock, the outstanding shares of Stock are increased or decreased or are exchanged for a different number or kind of shares or other securities of the Parent, or additional shares or new or different shares or other securities of the Parent or other non-cash assets are distributed with respect to such shares of Stock or other securities, or, if, as a result of any merger or consolidation, sale of all or substantially all of the assets of the Parent the outstanding shares of Stock are converted into or exchanged for securities of the Parent or any successor entity (or a parent or subsidiary thereof), the Administrator shall make an appropriate or proportionate adjustment in (i) the maximum number of shares reserved for issuance under the Plan, including the maximum number of shares that may be issued in the form of Incentive Stock Options, (ii) the number of Stock Options that can be granted to any one individual grantee and the maximum number of shares that may be granted under a Performance-Based Award, (iii) the number and kind of shares or other securities subject to any then outstanding Awards under the Plan, (iv) the repurchase price, if any, per share subject to each outstanding Restricted Stock Award, (v) the number of Stock Options automatically granted to Non-Employee Directors, and (vi) the price for each share subject to any then outstanding Stock Options under the Plan, without changing the aggregate exercise price (i.e., the exercise price multiplied by the number of Stock Options) as to which such Stock Options remain exercisable. The Administrator shall also make equitable or proportionate adjustments in the number of shares subject to outstanding Awards and the exercise price and the terms of outstanding Awards to take into consideration cash dividends paid other than in the ordinary course or any other extraordinary corporate event. The adjustment by the Administrator shall be final, binding and conclusive. No fractional shares of Stock shall be issued under the Plan resulting from any such adjustment, but the Administrator in its discretion may make a cash payment in lieu of fractional shares.

        (d)    Mergers and Other Transactions.    Except as the Administrator may otherwise specify with respect to particular Awards in the relevant Award documentation, in the case of and subject to the consummation of a Sale Event, all Options that are not exercisable immediately prior to the effective time of the Sale Event shall become fully exercisable as of the effective time of the Sale Event, all other Awards with time-based vesting, conditions or restrictions shall become fully vested and nonforfeitable as of the effective time of the Sale Event and all other Awards with conditions and restrictions relating to the attainment of performance goals may become vested and nonforfeitable in connection with a Sale Event in the Administrator's discretion. Upon the effective time of the Sale Event, the Plan and all outstanding Awards granted hereunder shall terminate, unless provision is made in connection with the Sale Event in the sole discretion of the parties thereto for the assumption or

A-5

continuation of Awards theretofore granted by the successor entity, or the substitution of such Awards with new Awards of the successor entity or parent thereof, with appropriate adjustment as to the number and kind of shares and, if appropriate, the per share exercise prices, as such parties shall agree (after taking into account any acceleration hereunder). In the event of such termination, the Company shall make or provide for a cash payment to the grantees holding Options, in exchange for the cancellation thereof, in an amount equal to the difference between (A) the Sale Price multiplied by the number of shares of Stock subject to outstanding Options (to the extent then exercisable (after taking into account any acceleration hereunder) at prices not in excess of the Sale Price) and (B) the aggregate exercise price of all such outstanding Options.

        (e)    Substitute Awards.    The Administrator may grant Awards under the Plan in substitution for stock and stock based awards held by employees, directors or other key persons of another corporation in connection with the merger or consolidation of the employing corporation with the Parent or a Subsidiary or the acquisition by the Parent or a Subsidiary of property or stock of the employing corporation. The Administrator may direct that the substitute awards be granted on such terms and conditions as the Administrator considers appropriate in the circumstances. Any substitute Awards granted under the Plan shall not count against the share limitation set forth in Section 3(a)(i).

SECTION 4.    ELIGIBILITY    

        Grantees under the Plan will be such full or part-time officers and other employees, Non-Employee Directors and key persons (including consultants and prospective employees) of the Parent and its Subsidiaries as are selected from time to time by the Administrator in its sole discretion.

SECTION 5.    STOCK OPTIONS    

        Any Stock Option granted under the Plan shall be in such form as the Administrator may from time to time approve.

        Stock Options granted under the Plan may be either Incentive Stock Options or Non-Qualified Stock Options. Incentive Stock Options may be granted only to employees of the Parent or any Subsidiary that is a "subsidiary corporation" within the meaning of Section 424(f) of the Code. To the extent that any Option does not qualify as an Incentive Stock Option, it shall be deemed a Non-Qualified Stock Option.

        (a)    Stock Options Granted to Employees and Key Persons.    The Administrator in its discretion may grant Stock Options to eligible employees and key persons of the Parent or any Subsidiary. Stock Options granted pursuant to this Section 5(a) shall be subject to the following terms and conditions and shall contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Administrator shall deem desirable. If the Administrator so determines, Stock Options may be granted in lieu of cash compensation at the optionee's election, subject to such terms and conditions as the Administrator may establish.

A-6

Payment instruments will be received subject to collection. The transfer to the optionee on the records of the Parent or of the transfer agent of the shares of Stock to be purchased pursuant to the exercise of a Stock Option will be contingent upon receipt from the optionee (or a purchaser acting in his stead in accordance with the provisions of the Stock Option) by the Parent of the full purchase price for such shares and the fulfillment of any other requirements contained in the Option Award Certificate or applicable provisions of laws (including the satisfaction of any withholding taxes that the Parent is obligated to withhold with respect to the optionee). In the event an optionee chooses to pay the purchase price by previously-owned shares of Stock through the attestation method, the number of shares of Stock transferred to the optionee upon the exercise of the Stock Option shall be net of the number of attested shares. In the event that the Parent establishes, for itself or using the services of a third party, an automated system for the exercise of Stock Options, such as a system using an internet website or interactive voice response, then the paperless exercise of Stock Options may be permitted through the use of such an automated system.

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        (v)    Annual Limit on Incentive Stock Options.    To the extent required for "incentive stock option" treatment under Section 422 of the Code, the aggregate Fair Market Value (determined as of the time of grant) of the shares of Stock with respect to which Incentive Stock Options granted under the Plan and any other plan of the Company or its parent and subsidiary corporations become exercisable for the first time by an optionee during any calendar year shall not exceed $100,000. To the extent that any Stock Option exceeds this limit, it shall constitute a Non-Qualified Stock Option.

        (b)   Stock Options Granted to Non-Employee Directors.

        (i)    Automatic Grant of Options.    

        (A)  Upon becoming a member of the Board, each Non-Employee Director who is not then a consultant to the Parent or its Subsidiaries shall be granted on such day a Non-Qualified Stock Option to acquire 35,000 shares of Stock, which shall vest ratably over the three calendar years following the date of grant, plus an additional Stock Option to acquire a number of shares of Stock equal to the product of 25,000 multiplied by a fraction, the numerator of which equals the number of months remaining until the next annual meeting of stockholders of the Parent and the denominator of which equals 12, which shall vest on the first anniversary of the date of grant.

        (B)  Each Non-Employee Director who is serving as Director of the Parent on each annual meeting of stockholders, beginning with the 2012 annual meeting, shall automatically be granted on such day a Non-Qualified Stock Option to acquire 25,000 shares of Stock, which shall vest on the first anniversary of the date of grant; provided, however, that no grant shall be made to an individual who ceases to be a member of the Board on such day.

        (C)  The exercise price per share for the Stock covered by a Stock Option granted under this Section 5(b) shall be equal to the Fair Market Value of the Stock on the date the Stock Option is granted.

        (D)  The Administrator, in its discretion, may grant additional Non-Qualified Stock Options to Non-Employee Directors. Any such grant may vary among individual Non-Employee Directors.

        (ii)    Exercise; Termination.    

        (A)  Unless otherwise determined by the Administrator, an Option granted under this Section 5(b) shall become vested and exercisable in accordance with the vesting provisions set forth in this Section 5(b). An Option issued under this Section 5(b) shall not be exercisable after the expiration of ten years from the date of grant.

        (B)  Options granted under this Section 5(b) may be exercised only by notice to the Parent (or the Parent's delegate) specifying the number of shares to be purchased. Payment of the full purchase price of the shares to be purchased may be made by one or more of the methods specified in Section 5(a)(iv). An optionee shall have the rights of a stockholder only as to shares acquired upon the exercise of a Stock Option and not as to unexercised Stock Options.

        (C)  Unless otherwise determined by the Administrator on or after the date of grant, if a Non-Employee Director's relationship with the Parent and its Subsidiaries terminates for any reason, the portion of each Stock Option held by the Non-Employee Director that is not then exercisable shall be immediately forfeited. Unless otherwise determined by the Administrator on or after the date of grant, the Non-Employee Director may exercise the exercisable portion of his Stock Options only to the extent set forth in his Stock Option Award Certificates.

        (iii)    Shares Available for Grant.    Grants of Stock Options contemplated by this Section 5(b) shall consist of shares of Stock reserved and available for issuance pursuant to the Alkermes plc Amended and Restated 2008 Stock Option and Incentive Plan, and if there are no such shares of Stock

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remaining, then such grants shall consist of shares of Stock reserved and available for issuance pursuant to the Plan.

SECTION 6.    RESTRICTED STOCK AWARDS    

        (a)    Nature of Restricted Stock Awards.    The Administrator shall determine the restrictions and conditions applicable to each Restricted Stock Award at the time of grant. Conditions may be based on continuing employment (or other service relationship) and/or achievement of pre-established performance goals and objectives. The terms and conditions of each Restricted Stock Award Certificate shall be determined by the Administrator, and such terms and conditions may differ among individual Awards and grantees.

        (b)    Rights as a Stockholder.    Upon the grant of a Restricted Stock Award and payment of any applicable purchase price, a grantee shall have the rights of a stockholder with respect to the voting of the Restricted Stock, subject to such conditions contained in the Restricted Stock Award Certificate. Unless the Administrator shall otherwise determine, (i) uncertificated Restricted Stock shall be accompanied by a notation on the records of the Parent or the transfer agent to the effect that they are subject to forfeiture until such Restricted Stock are vested as provided in Section 6(d) below, and (ii) certificated Restricted Stock shall remain in the possession of the Company until such Restricted Stock is vested as provided in Section 6(d) below, and the grantee shall be required, as a condition of the grant, to deliver to the Company such instruments of transfer as the Administrator may prescribe.

        (c)    Restrictions.    Restricted Stock may not be sold, assigned, transferred, pledged or otherwise encumbered or disposed of except as specifically provided herein or in the Restricted Stock Award Certificate. If a grantee's employment (or other service relationship) with the Parent and its Subsidiaries terminates for any reason (including if a Subsidiary ceases to be a Subsidiary of the Parent), any Restricted Stock that has not vested at the time of termination shall automatically, without any requirement of notice to such grantee from, or other action by or on behalf of, the Parent or its Subsidiaries, be deemed to have been reacquired by the Parent at its original purchase price (if any) from such grantee or such grantee's legal representative simultaneously with such termination of employment (or other service relationship), and thereafter shall cease to represent any ownership of the Parent by the grantee or rights of the grantee as a stockholder. Following such deemed reacquisition of unvested Restricted Stock that are represented by physical certificates, a grantee shall surrender such certificates to the Parent upon request without consideration.

        (d)    Vesting of Restricted Stock.    The Administrator at the time of grant shall specify the date or dates and/or the attainment of pre-established performance goals, objectives and other conditions on which the non-transferability of the Restricted Stock and the Parent's right of repurchase or forfeiture shall lapse. Notwithstanding the foregoing, in the event that any such Restricted Stock granted to employees shall have a performance-based goal, the restriction period with respect to such shares shall not be less than one year, and in the event any such Restricted Stock granted to employees shall have a time-based restriction, the total restriction period with respect to such shares shall not be less than three years; provided, however, that Restricted Stock with a time-based restriction may become vested incrementally over such three-year period. The Administrator may waive the foregoing restriction in the case of a grantee's death, disability or retirement or upon a Sale Event. Subsequent to such date or dates and/or the attainment of such pre-established performance goals, objectives and other conditions, the shares on which all restrictions have lapsed shall no longer be Restricted Stock and shall be deemed "vested." Except as may otherwise be provided by the Administrator pursuant to the authority reserved in this Section 6, a grantee's rights in any shares of Restricted Stock that have not vested shall automatically terminate upon the grantee's termination of employment (or other service relationship) with the Parent and its Subsidiaries for any reason (including if a Subsidiary ceases to be a Subsidiary of the Parent) and such shares shall be subject to the provisions of Section 6(c) above.

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SECTION 7.    RESTRICTED STOCK UNIT AWARDS    

        (a)    Nature of Restricted Stock Unit Awards.    The Administrator shall determine the restrictions and conditions applicable to each Restricted Stock Unit Award at the time of grant. Conditions may be based on continuing employment (or other service relationship) and/or achievement of pre-established performance goals and objectives. The terms and conditions of each Restricted Stock Unit Award Certificate shall be determined by the Administrator, and such terms and conditions may differ among individual Awards and grantees. Notwithstanding the foregoing, in the event that any such Restricted Stock Unit Award granted to employees shall have a performance-based goal, the restriction period with respect to such Award shall not be less than one year, and in the event any such Restricted Stock Unit Award granted to employees shall have a time-based restriction, the total restriction period with respect to such Award shall not be less than three years; provided, however, that any Restricted Stock Unit Award with a time-based restriction may become vested incrementally over such three-year period. The Administrator may waive the foregoing restriction in the case of a grantee's death, disability or retirement or upon a Sale Event. At the end of the restriction period, the Restricted Stock Unit Award, to the extent vested, shall be settled in the form of shares of Stock. To the extent that a Restricted Stock Unit Award is subject to Section 409A, it may contain such additional terms and conditions as the Administrator shall determine in its sole discretion in order for such Award to comply with the requirements of Section 409A.

        (b)    Election to Receive Restricted Stock Unit Awards in Lieu of Compensation.    The Administrator may, in its sole discretion, permit a grantee to elect to receive a portion of future cash compensation otherwise due to such grantee in the form of a Restricted Stock Unit Award. Any such election shall be made in writing and shall be delivered to the Company no later than the date specified by the Administrator and in accordance with Section 409A and such other rules and procedures established by the Administrator. Any such future cash compensation that the grantee elects to defer shall be converted to a fixed number of phantom stock units (which may be fully vested) based on the Fair Market Value of Stock on the date the compensation would otherwise have been paid to the grantee if such payment had not been deferred as provided herein. The Administrator shall have the sole right to determine whether and under what circumstances to permit such elections and to impose such limitations and other terms and conditions thereon as the Administrator deems appropriate.

        (c)    Rights as a Stockholder.    A grantee shall have the rights as a stockholder only as to shares of Stock acquired by the grantee upon settlement of a Restricted Stock Unit Award; provided, however, that the grantee may be credited with dividend equivalent rights with respect to the phantom stock units underlying his Restricted Stock Unit Award, subject to such terms and conditions as the Administrator may determine.

        (d)    Termination.    Except as may otherwise be provided by the Administrator pursuant to the authority reserved in Section 7(a), a grantee's right in all Restricted Stock Unit Awards that have not vested shall automatically terminate upon the grantee's termination of employment (or cessation of service relationship) with the Parent and its Subsidiaries for any reason (including if a Subsidiary ceases to be a Subsidiary of the Parent).

SECTION 8.    CASH-BASED AWARDS    

        Grant of Cash-Based Awards.    The Administrator may, in its sole discretion, grant Cash-Based Awards to any grantee in such number or amount and upon such terms, and subject to such conditions, as the Administrator shall determine at the time of grant. The Administrator shall determine the maximum duration of the Cash-Based Award, the amount of cash to which the Cash-Based Award pertains, the conditions upon which the Cash-Based Award shall become vested or payable, and such other provisions as the Administrator shall determine. Each Cash-Based Award shall specify a cash-denominated payment amount, formula or payment ranges as determined by the Administrator. Payment, if any, with respect to a Cash-Based Award shall be made in accordance with the terms of the

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Award and may be made in cash or in shares of Stock, as the Administrator determines. Except as may otherwise be provided by the Administrator pursuant to the authority reserved in this Section 8, a grantee's right in all Cash-Based Awards that have not vested shall automatically terminate upon the grantee's termination of employment (or cessation of service relationship) with the Parent and its Subsidiaries for any reason (including if a Subsidiary ceases to be a Subsidiary of the Parent).

SECTION 9.    PERFORMANCE SHARE AWARDS    

        (a)    Nature of Performance Share Awards.    The Administrator may, in its sole discretion, grant Performance Share Awards independent of, or in connection with, the granting of any other Award under the Plan. The Administrator shall determine whether and to whom Performance Share Awards shall be granted, the Performance Goals, the Performance Cycles, and such other limitations and conditions as the Administrator shall determine.

        (b)    Rights as a Stockholder.    A grantee receiving a Performance Share Award shall have the rights of a stockholder only as to shares actually received by the grantee under the Plan and not with respect to shares subject to the Award but not actually received by the grantee. A grantee shall be entitled to receive shares of Stock under a Performance Share Award only upon satisfaction of all conditions specified in the Performance Share Award Certificate (or in a performance plan adopted by the Administrator).

        (c)    Termination.    Except as may otherwise be provided by the Administrator either in the Award Certificate or, subject to Section 15 below, in writing after the Award Certificate is issued, a grantee's rights in all Performance Share Awards shall automatically terminate upon the grantee's termination of employment (or cessation of service relationship) with the Parent and its Subsidiaries for any reason (including if a Subsidiary ceases to be a Subsidiary of the Parent).

SECTION 10.    PERFORMANCE-BASED AWARDS TO COVERED EMPLOYEES    

        (a)    Performance-Based Awards.    Any Covered Employee who is selected by the Administrator may be granted one or more Performance-Based Awards payable upon the attainment of Performance Goals that are established by the Administrator and relate to one or more of the Performance Criteria, in each case on a specified date or dates or over any period or periods determined by the Administrator. The Administrator shall define in an objective fashion the manner of calculating the Performance Criteria it selects to use for any Performance Cycle. Depending on the Performance Criteria used to establish such Performance Goals, the Performance Goals may be expressed in terms of overall performance of the Parent or the performance of a Subsidiary, division, business unit, or an individual. The Administrator, in its discretion, may adjust or modify the calculation of Performance Goals for such Performance Cycle in order to prevent the dilution or enlargement of the rights of an individual (i) in the event of, or in anticipation of, any unusual or extraordinary corporate item, transaction, event or development, (ii) in recognition of, or in anticipation of, any other unusual or nonrecurring events affecting the Parent or its Subsidiaries, or the financial statements of the Parent or its Subsidiaries, or (iii) in response to, or in anticipation of, changes in applicable laws, regulations, accounting principles, or business conditions provided however, that the Administrator may not exercise such discretion in a manner that would increase the Performance-Based Award granted to a Covered Employee. Each Performance-Based Award shall comply with the provisions set forth below.

        (b)    Grant of Performance-Based Awards.    With respect to each Performance-Based Award granted to a Covered Employee, the Administrator shall select, within the first 90 days of a Performance Cycle (or, if shorter, within the maximum period allowed under Section 162(m) of the Code) the Performance Criteria for such grant, and the Performance Goals with respect to each Performance Criterion (including a threshold level of performance below which no amount will become payable with respect to such Award). Each Performance-Based Award will specify the amount payable, or the formula for determining the amount payable, upon achievement of the various applicable

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performance targets. The Performance Criteria established by the Administrator may be (but need not be) different for each Performance Cycle and different Performance Goals may be applicable to Performance-Based Awards to different Covered Employees.

        (c)    Payment of Performance-Based Awards.    Following the completion of a Performance Cycle, the Administrator shall meet to review and certify in writing whether, and to what extent, the Performance Goals for the Performance Cycle have been achieved and, if so, to also calculate and certify in writing the amount of the Performance-Based Awards earned for the Performance Cycle. The Administrator shall then determine the actual size of each Covered Employee's Performance-Based Award, and, in doing so, may reduce or eliminate the amount of the Performance-Based Award for a Covered Employee if, in its sole judgment, such reduction or elimination is appropriate.

        (d)    Maximum Award Payable.    The maximum Performance-Based Award payable to any one Covered Employee under the Plan for any twelve month period constituting all or part of a Performance Cycle is 4,000,000 Shares (subject to adjustment as provided in Section 3(b) hereof) or $25 million in the case of a Performance-Based Award that is a Cash-Based Award.

SECTION 11.    TRANSFERABILITY OF AWARDS    

        (a)    Transferability.    Except as provided in Section 11(b) below, during a grantee's lifetime, his or her Awards shall be exercisable only by the grantee, or by the grantee's legal representative or guardian in the event of the grantee's incapacity. No Awards shall be sold, assigned, transferred or otherwise encumbered or disposed of by a grantee other than by will or by the laws of descent and distribution or pursuant to a domestic relations order. No Awards shall be subject, in whole or in part, to attachment, execution, or levy of any kind, and any purported transfer in violation hereof shall be null and void.

        (b)    Administrator Action.    Notwithstanding Section 11(a), the Administrator, in its discretion, may provide either in the Award Certificate regarding a given Award or by subsequent written approval that the grantee (who is an employee or director) may transfer his or her Non-Qualified Stock Options to his or her immediate family members, to trusts for the benefit of such family members, or to partnerships in which such family members are the only partners, provided that the transferee agrees in writing with the Parent to be bound by all of the terms and conditions of the Plan and the applicable Award.

        (c)    Family Member.    For purposes of Section 11(b), "family member" shall mean a grantee's child, stepchild, grandchild, parent, stepparent, grandparent, spouse, former spouse, sibling, niece, nephew, mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or sister-in-law, including adoptive relationships, any person sharing the grantee's household (other than a tenant of the grantee), a trust in which these persons (or the grantee) have more than 50 percent of the beneficial interest, a foundation in which these persons (or the grantee) control the management of assets, and any other entity in which these persons (or the grantee) own more than 50 percent of the voting interests.

        (d)    Designation of Beneficiary.    Each grantee to whom an Award has been made under the Plan may designate a beneficiary or beneficiaries to exercise any Award or receive any payment under any Award payable on or after the grantee's death. Any such designation shall be on a form provided for that purpose by the Administrator and shall not be effective until received by the Administrator. If no beneficiary has been designated by a deceased grantee, or if the designated beneficiaries have predeceased the grantee, the beneficiary shall be the grantee's estate.

SECTION 12.    TAX WITHHOLDING    

        (a)    Payment by Grantee.    Each grantee shall, no later than the date as of which the value of an Award or of any Stock or other amounts received thereunder first becomes includable in the gross income of the grantee for Federal income tax purposes, pay to the Parent or its Subsidiaries, or make

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arrangements satisfactory to the Administrator regarding payment of, any Federal, state, or local taxes of any kind required by law to be withheld by the Parent or its Subsidiaries with respect to such income. The Parent and its Subsidiaries shall, to the extent permitted by law, have the right to deduct any such taxes from any payment of any kind otherwise due to the grantee. The Parent's obligation to deliver evidence of book entry (or stock certificates) to any grantee is subject to and conditioned on tax withholding obligations being satisfied by the grantee.

        (b)    Payment in Stock.    In connection with its obligations to withhold Federal, state, city or other taxes from amounts paid to grantees, the Parent or its Subsidiaries may make any arrangements that are consistent with the Plan as it may deem appropriate. Without limitation of the preceding sentence, the Parent shall have the right to reduce the number of shares of Stock otherwise required to be issued to a grantee (or other recipient) in an amount that would have a Fair Market Value on the date of such issuance equal to all Federal, state, city or other taxes as shall be required to be withheld by the Parent or its Subsidiaries pursuant to any statute or other governmental regulation or ruling and paid to any Federal, state, city or other taxing authority.

SECTION 13.    SECTION 409A AWARDS.    

        To the extent that any Award is determined to constitute "nonqualified deferred compensation" within the meaning of Section 409A (a "409A Award"), the Award shall be subject to such additional rules and requirements as specified by the Administrator from time to time in order to comply with Section 409A. In this regard, if any amount under a 409A Award is payable upon a "separation from service" (within the meaning of Section 409A) to a grantee who is then considered a "specified employee" (within the meaning of Section 409A), then no such payment shall be made prior to the date that is the earlier of (i) six months and one day after the grantee's separation from service, or (ii) the grantee's death, but only to the extent such delay is necessary to prevent such payment from being subject to interest, penalties and/or additional tax imposed pursuant to Section 409A. Further, the settlement of any such Award may not be accelerated except to the extent permitted by Section 409A.

SECTION 14.    TRANSFER, LEAVE OF ABSENCE, ETC.    

        For purposes of the Plan, the following events shall not be deemed a termination of employment:

        (a)   a transfer to the employment of the Parent from a Subsidiary or from the Parent to a Subsidiary, or from one Subsidiary to another;

        (b)   an approved leave of absence for military service or sickness, or for any other purpose approved by the Parent or its Subsidiaries, as the case may be, if the employee's right to re-employment is guaranteed either by a statute or by contract or under the policy pursuant to which the leave of absence was granted or if the Administrator otherwise so provides in writing; or

        (c)   the transfer in status from one eligibility category under Section 4 hereof to another category.

SECTION 15.    AMENDMENTS AND TERMINATION    

        The Board may, at any time, amend or discontinue the Plan and the Administrator may, at any time, amend or cancel any outstanding Award for the purpose of satisfying changes in law or for any other lawful purpose, but no such action shall adversely affect rights under any outstanding Award without the holder's consent. Except as provided in Section 3(c) or 3(d), without prior stockholder approval, in no event may the Administrator exercise its discretion to reduce the exercise price of outstanding Stock Options or effect repricing through cancellation and re-grants. To the extent required under the rules of any securities exchange or market system on which the Stock is listed, to the extent determined by the Administrator to be required by the Code to ensure that Incentive Stock Options granted under the Plan are qualified under Section 422 of the Code, or to ensure that compensation earned under Awards qualifies as performance-based compensation under Section 162(m) of the Code, Plan amendments shall be subject to approval by the stockholders of the Parent entitled to vote at a

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meeting of stockholders. Nothing in this Section 15 shall limit the Administrator's authority to take any action permitted pursuant to Section 3(d).

SECTION 16.    STATUS OF PLAN    

        With respect to the portion of any Award that has not been exercised and any payments in cash, Stock or other consideration not received by a grantee, a grantee shall have no rights greater than those of a general creditor of the Parent unless the Administrator shall otherwise expressly determine in connection with any Award or Awards. In its sole discretion, the Administrator may authorize the creation of trusts or other arrangements to meet the Parent's obligations to deliver Stock or make payments with respect to Awards hereunder, provided that the existence of such trusts or other arrangements is consistent with the foregoing sentence.

SECTION 17.    GENERAL PROVISIONS    

        (a)    No Distribution.    The Administrator may require each person acquiring Stock pursuant to an Award to represent to and agree with the Parent in writing that such person is acquiring the shares without a view to distribution thereof.

        (b)    Delivery of Stock Certificates.    Stock certificates to grantees under the Plan shall be deemed delivered for all purposes when the Parent or a stock transfer agent of the Parent shall have mailed such certificates in the United States mail, addressed to the grantee, at the grantee's last known address on file with the Parent. Uncertificated Stock shall be deemed delivered for all purposes when the Parent or a Stock transfer agent of the Parent shall have given to the grantee by electronic mail (with proof of receipt) or by United States mail, addressed to the grantee, at the grantee's last known address on file with the Parent or any Subsidiary, notice of issuance and recorded the issuance in its records (which may include electronic "book entry" records). Notwithstanding anything herein to the contrary, the Parent shall not be required to issue or deliver any certificates evidencing shares of Stock pursuant to the exercise of any Award, unless and until the Administrator has determined, with advice of counsel (to the extent the Administrator deems such advice necessary or advisable), that the issuance and delivery of such certificates is in compliance with all applicable laws, regulations of governmental authorities and, if applicable, the requirements of any exchange on which the shares of Stock are listed, quoted or traded. All Stock certificates delivered pursuant to the Plan shall be subject to any stop-transfer orders and other restrictions as the Administrator deems necessary or advisable to comply with federal, state or foreign jurisdiction, securities or other laws, rules and quotation system on which the Stock is listed, quoted or traded. The Administrator may place legends on any Stock certificate to reference restrictions applicable to the Stock. In addition to the terms and conditions provided herein, the Administrator may require that an individual make such reasonable covenants, agreements, and representations as the Administrator, in its discretion, deems necessary or advisable in order to comply with any such laws, regulations, or requirements. The Administrator shall have the right to require any individual to comply with any timing or other restrictions with respect to the settlement or exercise of any Award, including a window-period limitation, as may be imposed in the discretion of the Administrator.

        (c)    Stockholder Rights.    Until Stock is deemed delivered in accordance with Section 17(b), no right to vote or receive dividends or any other rights of a stockholder will exist with respect to shares of Stock to be issued in connection with an Award, notwithstanding the exercise of a Stock Option or any other action by the grantee with respect to an Award.

        (d)    Other Compensation Arrangements; No Employment Rights.    Nothing contained in the Plan shall prevent the Board from adopting other or additional compensation plans or arrangements, including trusts, and such arrangements may be either generally applicable or applicable only in specific cases. The adoption of the Plan and the grant of Awards do not confer upon any employee any right to continued employment with the Parent or any Subsidiary.

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        (e)    Trading Policy Restrictions.    Option exercises and other Awards under the Plan shall be subject to the Parent's insider trading policies and procedures, as in effect from time to time.

        (f)    Forfeiture of Awards under Sarbanes-Oxley Act.    If the Parent is required to prepare an accounting restatement due to the material noncompliance of the Parent , as a result of misconduct, with any financial reporting requirement under the securities laws, then any grantee who is one of the individuals subject to automatic forfeiture under Section 304 of the Sarbanes-Oxley Act of 2002 shall reimburse the Parent for the amount of any Award received by such individual under the Plan during the 12-month period following the first public issuance or filing with the United States Securities and Exchange Commission, as the case may be, of the financial document embodying such financial reporting requirement.

        (g)    Section 60 of Irish Companies Act 1963.    The Parent and any Subsidiary incorporated in Ireland may do all such things as are contemplated by the Plan except to the extent that they are prohibited by Section 60 of the Irish Companies Act 1963. Nothing in this Section 17 (g) shall prohibit anything which may be done as contemplated by the Plan by a Subsidiary which is incorporated outside of Ireland.

SECTION 18.    EFFECTIVE DATE OF PLAN    

        The Plan shall become effective upon approval by the holders of a majority of the votes cast at a meeting of stockholders at which a quorum is present No grants of Stock Options and other Awards may be made hereunder after the tenth anniversary of the Effective Date and no grants of Incentive Stock Options may be made hereunder after the tenth anniversary of the date the Plan is approved by the Board.

SECTION 19.    GOVERNING LAW    

        This Plan and all Awards and actions taken thereunder shall be governed by, and construed in accordance with, the laws of the Commonwealth of Massachusetts, applied without regard to conflict of law principles.

SECTION 20.    DISPUTE RESOLUTION    

        All disputes and differences arising out of the Plan or otherwise in connection therewith may be referred by the Parent to arbitration pursuant to the procedures set forth in the applicable grant agreement of any grantee so affected.

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 APPENDIX B

DIRECTORS' REPORT

For the Year Ended March 31, 2012

        No portion of this Directors' Report shall be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, through any general statement incorporating by reference in its entirety the proxy statement in which this report appears, except to the extent that the Company specifically incorporates this report or a portion of it by reference. In addition, this report shall not be deemed filed under either the Securities Act or the Exchange Act.

        The directors present their report and audited consolidated financial statements for the fiscal year ended March 31, 2012.

        The directors have elected to prepare the consolidated financial statements in accordance with section 1 of the Companies (Miscellaneous Provisions) Act, 2009, which provides that a true and fair view of the state of affairs and profit or loss may be given by preparing the financial statements in accordance with accounting principles generally accepted in the United States of America ("GAAP"), as defined in Section 1(1) of the Companies (Miscellaneous Provisions) Act 2009, to the extent that the use of those principles in the preparation of the financial statements does not contravene any provision of the Companies Acts or of any regulations made thereunder.

Principal Activities

        Alkermes plc develops medicines that address the unmet needs and challenges of people living with serious chronic disease. A fully integrated global biopharmaceutical company, Alkermes applies proven scientific expertise, proprietary technologies and global development capabilities to create innovative treatments for major clinical conditions with a focus on central nervous system ("CNS") disorders, such as schizophrenia, addiction and depression.

        We create new, proprietary pharmaceutical products for our own account, and we collaborate with other pharmaceutical and biotechnology companies. We are increasingly focused on maintaining rights to commercialize our leading product candidates in certain markets.

        We are an Irish public limited company incorporated in Dublin, Ireland, with a research and development ("R&D") center in Waltham, Massachusetts and manufacturing facilities in Athlone, Ireland; Gainesville, Georgia; and Wilmington, Ohio. Our corporate headquarters are located at Connaught House, 1 Burlington Road, Dublin 4, Ireland.

        Use of the terms such as "us," "we," "our," "Alkermes" or the "Company" in this Directors' Report is meant to refer to Alkermes plc and its subsidiaries, except when the context makes clear that the time period being referenced is prior to September 16, 2011, in which case such terms shall refer to Alkermes, Inc. ("Old Alkermes"). Prior to September 16, 2011, Alkermes, Inc. was an independent pharmaceutical company incorporated in the Commonwealth of Pennsylvania, United States ("U.S.") and traded on the NASDAQ Global Select Stock Market under the symbol "ALKS."

Business Combination

        On September 16, 2011, the business of Alkermes, Inc. and the drug technologies business ("EDT") of Elan Corporation, plc ("Elan") were combined (this combination is referred to as the "Business Combination", the "acquisition of EDT" or the" EDT acquisition"). The historical financial statements of Alkermes, Inc. are included in the comparative prior periods. As part of the Business Combination, Antler Acquisition Corp., a wholly owned subsidiary of the Company, merged with and into Alkermes, Inc. (the "Merger"), with Alkermes, Inc. surviving as a wholly owned subsidiary of the

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Company. Prior to the Merger, EDT was carved-out of Elan and reorganized under the Company. At the effective time of the Merger, (i) each share of Alkermes, Inc. common shares then issued and outstanding and all associated rights were canceled and automatically converted into the right to receive one ordinary share of the Company; (ii) all then issued and outstanding options to purchase Alkermes, Inc. common shares granted under any share option plan were converted into options to purchase, on substantially the same terms and conditions, the same number of ordinary shares of the Company at the same exercise price; and (iii) all then issued and outstanding awards of Alkermes, Inc. common shares were converted into awards of the same number, on substantially the same terms and conditions, of ordinary shares of the Company. As a result, upon consummation of the Merger and the issuance of the ordinary shares of the Company in exchange for the canceled shares of Alkermes, Inc. common shares, the former shareholders of Alkermes, Inc. owned approximately 75% of the Company, with the remaining approximately 25% of the Company owned by a subsidiary of Elan pursuant to the terms of a shareholder's agreement. As of March 31, 2012, Elan, through its subsidiary, owned approximately 6% of the Company's outstanding ordinary shares.

Business Overview

Commercial Products

        Our commercial products are described in the table below, including, among other things, the territory where currently sold and the source of revenues for us.

Product
  Indication   Technology   Territory   Revenue Source   Marketer
RISPERDAL
CONSTA		   Schizophrenia
Bipolar I Disorder		   Extended-release
microsphere		   Worldwide   Manufacturing and
Royalty		   Janssen
INVEGA
SUSTENNA
XEPLION		   Schizophrenia   NanoCrystal®   Worldwide   Royalty   Janssen
AMPRYA
FAMPYRA		   Treatment for multiple sclerosis ("MS")   OCR
(MXDAS®)		   U.S.
United Kingdom,
Australia,
Germany,
Norway,
Denmark
Iceland, Canada		   Manufacturing and
Royalty		   Acorda Therapeutics, Inc. in U.S. Biogen Idec (ex-U.S. under sublicense from Acorda)
BYDUREON   Type 2 diabetes   Extended-release
microsphere		   U.S.
European Union
U.A.E.		   Royalty   Amylin
VIVITROL   Alcohol dependence
Opioid dependence		   Extended-release
microsphere		   U.S.
Russia and Commonwealth of Independent States ("CIS")		   Product sales
Manufacturing and
Royalty		   Alkermes plc
Janssen
TRICOR®
LIPANTHYL®
LIPIDIL®
SUPRALIP®		   Cholesterol lowering   NanoCrystal   Worldwide   Royalty   Abbott
ZANAFLEX®
CAPSULES®
ZANAFLEX®
TABLETS		   Muscle spasticity   OCR
(SODAS®)		   U.S.   Manufacturing and
Royalty		   Acorda
AVINZA®   Chronic moderate to severe pain   OCR
(SODAS)		   U.S.   Manufacturing and
Royalty		   Pfizer
EMEND®   Nausea associated with
chemotherapy and surgery		   NanoCrystal   Worldwide   Royalty   Merck
FOCALIN® XR
RITALIN LA®		   Attention Deficit
Hyperactivity
Disorder		   OCR
(SODAS)		   Worldwide   Manufacturing and
Royalty		   Novartis

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Product
  Indication   Technology   Territory   Revenue Source   Marketer
MEGACE® ES   Cachexia associated
with AIDS		   NanoCrystal   U.S.   Royalty   Strativa Pharmaceuticals (a business division of Par Pharmaceutical Companies, Inc.)
LUVOX CR®   Obsessive-compulsive
disorder		   OCR
(SODAS)		   U.S.   Manufacturing and
Royalty		   Jazz
Pharmaceuticals plc
RAPAMUNE®   Prevention of renal transplant
rejection		   NanoCrystal   Worldwide   Manufacturing   Pfizer
NAPRELAN®   Various mild to moderate
pain indications		   OCR
(IPDAS®)		   U.S.
Canada		   Manufacturing   Shionogi
Sunovion
Pharmaceuticals Canada,
Inc.
VERAPAMIL SR
VERELAN®
VERELAN® PM
VERAPAMIL PM
VERECAPS®
UNIVER®		   Hypertension   OCR
(SODAS)		   Licensed on
country/region
basis throughout
the world		   Manufacturing   UCB
Kremers-Urban Watson;
Cephalon;
Aspen;
Orient Europharma
DILZEM SR
DILZEM XL
DILTELAN
ACALIX CD
DINISOR
TILAZEM CR
CARDIZEM CD		   Hypertension and/or Angina   OCR
(SODAS)		   Licensed on
country/region
basis throughout
the world		   Manufacturing and
Royalty (for CARDIZEM
CD only)		   Cephalon;
Pfizer;
Roemmers;
Kun Wha;
Orient Europharma;
Sanofi-Aventis

AFE Ditab® CR
(AB Rated to
Adalat CC®)
(Nifedipine)
(A)

   Hypertension   OCR
(MXDAS®)		   U.S.   Manufacturing   Watson Pharmaceutical

        We have five principal commercial products which either currently, or in the future, are expected to contribute meaningfully to our revenues.

RISPERDAL CONSTA and INVEGA SUSTENNA/XEPLION

        RISPERDAL CONSTA and INVEGA SUSTENNA/XEPLION, which are two long-acting atypical antipsychotics, incorporate our extended-release injectable technology. They are products of Janssen.

        RISPERDAL CONSTA is the first and only long-acting, atypical antipsychotic approved by the U.S. Food and Drug Administration ("FDA") for the treatment of schizophrenia and for the treatment of bipolar I disorder. INVEGA SUSTENNA/XEPLION is a once-monthly, long-acting injectable atypical antipsychotic approved by the FDA for the acute and maintenance treatment of schizophrenia in adults.

        Revenues from Janssen accounted for approximately 48%, 83% and 83% of our consolidated revenues for the fiscal years ended March 31, 2012, 2011 and 2010, respectively. See "Collaborative Arrangements" below for information about our relationship with Janssen.

For the treatment of schizophrenia

        RISPERDAL CONSTA (risperidone long-acting injection) uses our polymer-based microsphere injectable extended-release technology to deliver and maintain therapeutic medication levels in the body through just one injection every two weeks. RISPERDAL CONSTA is exclusively manufactured by us and is marketed and sold by Janssen in more than 90 countries, including the U.S., United Kingdom ("UK"), Japan, Italy, Spain and Germany. It was first approved for the treatment of schizophrenia in the U.S. in 2003 and in countries in Europe in 2002.

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        INVEGA SUSTENNA (paliperidone palmitate) uses our nanoparticle injectable extended-release technology to increase the rate of dissolution and enable the formulation of an aqueous suspension for once-monthly intramuscular administration. INVEGA/SUSTENNA was approved in the U.S. in 2009. Paliperidone palmitate extended-release for injectable suspension is also approved in the European Union ("EU") and other countries worldwide, and is marketed and sold in the EU under the trade name XEPLION. INVEGA SUSTENNA/XEPLION is manufactured and commercialized by Janssen.

What is schizophrenia?

        Schizophrenia is a chronic, severe and disabling brain disorder. The disease is marked by positive symptoms (hallucinations and delusions) and negative symptoms (depression, blunted emotions and social withdrawal), as well as by disorganized thinking. An estimated 2.4 million Americans have schizophrenia, with men and women affected equally. Worldwide, it is estimated that one person in every 100 develops schizophrenia. Studies have demonstrated that as many as 75% of patients with schizophrenia have difficulty taking their oral medication on a regular basis, which can lead to worsening of symptoms.

For the treatment of bipolar I disorder

        The FDA approved RISPERDAL CONSTA as both monotherapy and adjunctive therapy to lithium or valproate in the maintenance treatment of bipolar I disorder in May 2009. RISPERDAL CONSTA is also approved for the maintenance treatment of bipolar I disorder in Canada, Australia and Saudi Arabia.

What is bipolar I disorder?

        Bipolar disorder is a brain disorder that causes unusual shifts in a person's mood, energy and ability to function. It is often characterized by debilitating mood swings, from extreme highs (mania) to extreme lows (depression). Bipolar I disorder is characterized based on the occurrence of at least one manic episode, with or without the occurrence of a major depressive episode. Bipolar disorder is believed to affect approximately 5.7 million American adults, or about 2.6% of the U.S. population aged 18 and older in a given year. The median age of onset for bipolar disorder is 25 years.

AMPYRA/FAMPYRA

        Dalfampridine extended-release tablets are marketed and sold in the U.S. under the trade name AMPYRA by Acorda. Prolonged-release fampridine tablets are marketed and sold outside the U.S. under the trade name FAMPYRA by Biogen Idec. AMPYRA was approved by the FDA in January 2010 as a treatment to improve walking in patients with MS as demonstrated by an increase in walking speed. Efficacy was shown in people with all four major types of MS (relapsing remitting, secondary progressive, progressive relapsing and primary progressive). It is the first and, currently, only product to be approved for this indication. A product of Acorda, it incorporates our Oral Controlled Release ("OCR") technology. FAMPYRA received conditional marketing approval in the EU in July 2011 and is currently being sold by Biogen Idec in select European countries, as well as Australia. AMPYRA and FAMPYRA are manufactured by us.

What is multiple sclerosis?

        MS is a chronic, usually progressive disease in which the immune system attacks and degrades the function of nerve fibers in the brain and spinal cord. These nerve fibers consist of long, thin fibers, or axons, surrounded by a myelin sheath, which facilitates the transmission of electrical impulses. In MS, the myelin sheath is damaged by the body's own immune system, causing areas of myelin sheath loss, also known as demyelination. This damage, which can occur at multiple sites in the CNS, blocks or

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diminishes conduction of electrical impulses. People with MS may suffer impairments in any number of neurological functions. These impairments vary from individual to individual and over the course of time, depending on which parts of the brain and spinal cord are affected, and often include difficulty walking. Individuals vary in the severity of the impairments they suffer on a day-to-day basis, with impairments becoming better or worse depending on the activity of the disease on a given day.

BYDUREON

        We collaborated with Amylin on the development of a once-weekly formulation of exenatide, BYDUREON, for the treatment of type 2 diabetes. BYDUREON, an injectable formulation of Amylin's BYETTA® (exenatide), uses our polymer-based microsphere injectable extended-release technology. Amylin is responsible for commercializing exenatide products, including BYDUREON, in the U.S. Eli Lilly and Company ("Lilly") has exclusive rights to commercialize exenatide products outside of the U.S. until December 31, 2013 or such earlier date as agreed upon between Lilly and Amylin pursuant to the terms of their transition agreement, following which Amylin will have such exclusive rights.

        In June 2011, the European Commission granted marketing authorization for BYDUREON for the treatment of type 2 diabetes in adult patients in combination with metformin, a sulfonylurea, a thiazolidinedione, metformin plus a sulfonylurea or metformin plus a thiazolidinedione. In July 2011, Lilly launched BYDUREON in the UK, and in September 2011, BYDUREON was launched in Germany. We received a $7.0 million milestone payment upon first commercial sale of BYDUREON in the EU, which was recognized during the quarter ended September 30, 2011.

        In January 2012, the FDA approved BYDUREON as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes. We received a $7.0 million milestone payment upon first commercial sale of BYDUREON in the U.S., which was recognized as revenue during the quarter ended March 31, 2012. BYDUREON was launched in the U.S. in February 2012.

What is type 2 diabetes?

        Diabetes is a disease in which the body does not produce or properly use insulin. Diabetes can result in serious health complications, including cardiovascular, kidney and nerve disease. Diabetes is believed to affect nearly 26 million people in the U.S. and an estimated 347 million adults worldwide. Approximately 90-95% of those affected have type 2 diabetes. According to the U.S. Centers for Disease Control and Prevention's National Health and Nutrition Examination Survey, approximately 60% of people with diabetes do not achieve their target blood sugar levels with their current treatment regimen. In addition, 85% of type 2 diabetes patients are overweight and 55% are considered obese. Data indicate that weight loss (even a modest amount) supports patients in their efforts to achieve and sustain glycemic control.

VIVITROL

        VIVITROL is the first and only once-monthly injectable medication for the treatment of alcohol dependence and the prevention of relapse to opioid dependence, following opioid detoxification. The medication uses our polymer-based microsphere injectable extended-release technology to deliver and maintain therapeutic medication levels in the body through just one injection every four weeks. We developed, and currently market and sell, VIVITROL in the U.S.

        VIVITROL was approved by the FDA for the treatment of alcohol dependence in April 2006 and was launched in the U.S. for this indication in June 2006. The FDA approved VIVITROL for the prevention of relapse to opioid dependence, following opioid detoxification, in October 2010.

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        In December 2007, we exclusively licensed the right to commercialize VIVITROL for the treatment of alcohol dependence and opioid dependence in Russia and other countries in the CIS to Cilag. In August 2008, the Russian regulatory authorities approved VIVITROL for the treatment of alcohol dependence, and Cilag launched VIVITROL in Russia in March 2009. The Russian regulatory authorities approved VIVITROL for the prevention of relapse to opioid dependence following opioid detoxification in April 2011.

What are opioid dependence and alcohol dependence?

        Opioid dependence is a serious and chronic brain disease characterized by compulsive, prolonged self-administration of opioid substances that are not used for a medical purpose. According to the 2010 U.S. National Survey on Drug Use and Health, an estimated 1.5 million people aged 18 or older were dependent on pain relievers or heroin.

        Alcohol dependence is a serious and chronic brain disease characterized by cravings for alcohol, loss of control over drinking, withdrawal symptoms and an increased tolerance for alcohol. Approximately 18 million people in the U.S. are dependent on or abuse alcohol, half of whom are considered to be alcohol dependent. Adherence to medication is particularly challenging with this patient population.

Other Commercial Products

        We expect revenues from our other commercial products will decrease in the future due to existing and expected competition from generic manufacturers. For a more detailed discussion of current and expected future revenue contribution of such products, please see "Management's Discussion and Analysis of Financial Condition and Results of Operations" elsewhere in this Annual Report.

Key Development Programs

ALKS 9070

        We are studying ALKS 9070 for the treatment of schizophrenia. ALKS 9070 is an injectable, sustained-release product candidate designed to provide once-monthly dosing of a medication that converts in vivo into aripiprazole, a molecule that is commercially available under the name ABILIFY®. ALKS 9070 is our first product candidate to leverage our proprietary LinkeRx™ product platform. In June 2011, we announced positive results from a phase 1b, double-blind, randomized, placebo- controlled, 20-week study that assessed the safety, tolerability and pharmacokinetic profile of a single administration of three ascending doses of ALKS 9070 in 32 patients with chronic, stable schizophrenia. Data from the study showed that ALKS 9070 was generally well tolerated, achieved therapeutically relevant plasma concentrations of aripiprazole with a pharmacokinetic profile that supports once-monthly dosing. In December 2011, based on these results, we advanced ALKS 9070 into a multicenter, double-blind, placebo-controlled phase 3 study designed to assess the efficacy, safety and tolerability of ALKS 9070 in approximately 690 patients experiencing acute exacerbation of schizophrenia; these patients will be randomized to receive one of two doses of ALKS 9070 or placebo. The clinical data from this study, which are expected mid-calendar year 2013, may form the basis of an NDA to the FDA for ALKS 9070 for the treatment of schizophrenia.

        During the three months ended March 31, 2012, we transferred ALKS 9070, including all ALKS 9070 intellectual property, from the U.S. to Ireland.

ALKS 37

        We are developing ALKS 37, an orally active, peripherally restricted opioid antagonist for the treatment of opioid-induced constipation ("OIC"). According to IMS Health information, an estimated

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280 million prescriptions were written for opioids in the U.S. during 2010. Many studies indicate that a high percentage of patients receiving opioids are likely to experience side effects affecting gastrointestinal motility. OIC can be severe and adversely impact quality of life, compromising patient compliance with opioid therapy in order to achieve pain management.

        In May 2011, we presented positive results from a phase 2 double-blind, randomized, placebo-controlled, multidose clinical study of ALKS 37 for the treatment of OIC. Data from the study showed that ALKS 37 significantly improved gastrointestinal motility, demonstrated by increased frequency of bowel movements in patients with OIC, while simultaneously preserving the analgesic effects of opioid treatment. The study also demonstrated that ALKS 37 was generally well tolerated. In July 2011, we announced the initiation of a multicenter, randomized, double-blind, placebo-controlled, repeat-dose phase 2b study of ALKS 37 to assess the safety, tolerability, efficacy and pharmacokinetic profile of ALKS 37 in approximately 150 patients. In October 2011, we announced the initiation of a second phase 2b study of ALKS 37. This multicenter, randomized, double-blind, placebo-controlled, fixed-dose study is designed to assess the safety and efficacy of daily administration of a 100 mg dose of ALKS 37 versus placebo for 12 weeks in approximately 80 patients with OIC. The results of this phase 2b study, along with those from the repeat-dose, four-week phase 2b study initiated earlier in 2011, are expected in mid-calendar year 2012.

ALKS 33

        ALKS 33 is an oral opioid modulator characterized by limited hepatic metabolism and durable pharmacologic activity in modulating brain opioid receptors.

        We conducted two phase 1 studies and one phase 2 study of ALKS 33. The first phase 1 study was a randomized, double-blind, placebo-controlled, multidose study designed to assess the steady-state pharmacokinetics, safety and tolerability of ALKS 33. In the study, ALKS 33 demonstrated rapid oral absorption and sustained pharmacologically active plasma levels supporting once-daily dosing. The second phase 1 study was a randomized, single-blind, placebo-controlled, single-dose study designed to test the ability of ALKS 33 to block the subjective and objective effects of a potent opioid agonist, remifentanil, a commercially available analgesic. Data showed that the onset of action of ALKS 33 was rapid and observed as early as 15 minutes following oral administration. A full blockade of the opioid agonist was observed and sustained for more than 24 hours following a single administration of ALKS 33. ALKS 33 was generally well tolerated in both studies.

        The phase 2 study of ALKS 33 was designed to assess the safety, tolerability, pharmacokinetics and efficacy of daily oral administration of three different dose levels of ALKS 33 compared to placebo in 400 alcohol dependent patients. The phase 2 study showed that ALKS 33 was generally well tolerated and characterized by its potential for daily dosing, non-hepatic metabolism, extended pharmacologic benefit in the event of missed doses and pharmacologic activity in reducing heavy drinking behavior. ALKS 33 is currently being evaluated as a potential treatment for alcohol dependence. There are currently no ongoing clinical trials of ALKS 33 for the treatment of alcohol dependence.

ALKS 5461

        ALKS 5461 is a combination of ALKS 33 and buprenorphine that we are developing to be a non-addictive therapy for the treatment of major depressive disorder ("MDD"), in patients who have an inadequate response to standard antidepressant therapies, and for the treatment of cocaine dependence.

Major Depressive Disorder

        In January 2012, we announced positive results from a phase 1/2 study of ALKS 5461 compared to placebo in 32 patients with MDD who did not adequately respond to standard antidepressant therapies.

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In the study, ALKS 5461 was shown to significantly reduce depressive symptoms, as measured by the Hamilton Depression Rating Scale (HAM-D17; a standard, clinician-assessed measure of depression severity), in patients who received ALKS 5461 for the seven-day treatment period. In addition, data from the study showed that ALKS 5461 was generally well tolerated. Based on these results, we initiated a randomized, double-blind, multicenter, placebo-controlled phase 2 study to evaluate the efficacy and safety of ALKS 5461 when administered once daily for four weeks in approximately 130 patients with MDD who have inadequate response to antidepressant therapy. Data from the study are expected in the first half of calendar year 2013.

Cocaine Dependence

        Our randomized, double-blind, multidose, placebo-controlled phase 1 clinical study assessed the safety, tolerability and pharmacodynamic effects of the combination of ALKS 33 and buprenorphine when administered alone, and in combination as ALKS 5461, to 12 opioid-experienced users. Data from the study showed that ALKS 5461 was generally well-tolerated and sublingual administration of ALKS 33 effectively blocked the agonist effects of buprenorphine.

        Based on these positive results, we filed an Investigational New Drug application ("IND") for ALKS 5461 for the treatment of cocaine dependence in June 2011. In the second half of 2011, we initiated a phase 1b study of ALKS 5461 for cocaine dependence, which is being funded through a grant from the National Institute on Drug Abuse ("NIDA"). NIDA has granted us up to $2.4 million to accelerate the clinical development of ALKS 5461 for the treatment of cocaine dependence. Currently, there are no medications approved for the treatment of cocaine dependence. The results of this phase 1b study are expected in mid-calendar year 2012.

ZOHYDRO™

        ZOHYDRO (hydrocodone bitartrate) extended-release capsules is a novel, oral, single-entity (without acetaminophen), controlled-release formulation of hydrocodone in development by Zogenix, Inc. ("Zogenix") for the U.S. market. ZOHYDRO utilizes our oral controlled-release technology, which potentially enables longer-lasting and more consistent pain relief with fewer daily doses than the commercially available formulations of hydrocodone. In August 2011, Zogenix announced positive top-line results from its pivotal phase 3 efficacy study of ZOHYDRO for the treatment of moderate to severe chronic pain in patients requiring around-the-clock opioid therapy. On May 2, 2012, Zogenix announced that it submitted a NDA to the FDA for ZOHYDRO. We will earn manufacturing revenues in the U.S. for ZOHYDRO and are entitled to receive a royalty on U.S. sales of ZOHYDRO, if approved. We have maintained all rights to the product in territories outside the U.S. and will seek to develop and license the product through commercial partnerships in those territories.

Our Research and Development Expenditures

        We devote significant resources to R&D programs. We focus our R&D efforts on identifying novel therapeutics in areas of high unmet medical need. Please see "Item 6. Selected Financial Data" for our R&D expenditures for our previous five fiscal years.

Collaborative Arrangements

        Our business strategy includes forming collaborations to develop and commercialize our products and, in so doing, access technological, financial, marketing, manufacturing and other resources. We have entered into several collaborative arrangements, as described below.

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Janssen

RISPERDAL CONSTA

        Under a product development agreement, we collaborated with Janssen on the development of RISPERDAL CONSTA. Under the development agreement, Janssen provided funding to us for the development of RISPERDAL CONSTA, and Janssen is responsible for securing all necessary regulatory approvals for the product.

        Under license agreements, we granted Janssen and an affiliate of Janssen exclusive worldwide licenses to use and sell RISPERDAL CONSTA. Under our license agreements with Janssen, we receive royalty payments equal to 2.5% of Janssen's net sales of RISPERDAL CONSTA in each country where the license is in effect based on the quarter when the product is sold by Janssen. This royalty may be reduced in any country based on lack of patent coverage and significant competition from generic versions of the product. Janssen can terminate the license agreements upon 30 days' prior written notice to us. The licenses granted to Janssen expire on a country-by-country basis upon the later of (i) the expiration of the last patent claiming the product in such country or (ii) fifteen years after the date of the first commercial sale of the product in such country, provided that in no event will the license granted to Janssen expire later than the twentieth anniversary of the first commercial sale of the product in such country, with the exception of certain countries where the fifteen-year limitation shall pertain regardless. After expiration, Janssen retains a non-exclusive, royalty-free license to manufacture, use and sell RISPERDAL CONSTA. We exclusively manufacture RISPERDAL CONSTA for commercial sale. Under our manufacturing and supply agreement with Janssen, we record manufacturing revenues when product is shipped to Janssen, based on 7.5% of Janssen's net unit sales price for RISPERDAL CONSTA for the calendar year.

        The manufacturing and supply agreement terminates on expiration of the license agreements. In addition, either party may terminate the manufacturing and supply agreement upon a material breach by the other party, which is not resolved within 60 days after receipt of a written notice specifying the material breach or upon written notice in the event of the other party's insolvency or bankruptcy. Janssen may terminate the agreement upon six months' written notice to us. In the event that Janssen terminates the manufacturing and supply agreement without terminating the license agreements, the royalty rate payable to us on Janssen's net sales of RISPERDAL CONSTA would increase from 2.5% to 5.0%.

INVEGA SUSTENNA/XEPLION

        Under our license agreement with Janssen Pharmaceutica N.V., we granted Janssen a worldwide exclusive license under our NanoCrystal technology to develop, commercialize and manufacture INVEGA SUSTENNA/XEPLION and related products.

        Under our license agreement, we receive certain development milestone payments from Janssen and tiered royalty payments between 5% and 9% of INVEGA SUSTENNA net sales in each country where the license is in effect, with the exact royalty percentage determined based on worldwide net sales. These royalty payments may be reduced in any country based on lack of patent coverage or patent litigation, or where competing products achieve certain minimum sales thresholds. The licenses granted to Janssen expire on a country-by-country basis upon the later of (i) March 31, 2019 or (ii) the expiration of the last of the patents claiming the product in such country. After expiration, Janssen retains a non-exclusive, royalty-free license to develop, manufacture and commercialize the products.

        Janssen may terminate the license agreement in whole or in part upon three months' notice to us. We and Janssen have the right to terminate the agreement upon a material breach of the other party, which is not cured within a certain time period or upon the other party's bankruptcy or insolvency.

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Acorda

        Under an amended and restated license agreement, we granted Acorda an exclusive worldwide license to use and sell and, solely in accordance with our supply agreement, to make or have made, AMPYRA/FAMPYRA. Under our license agreement with Acorda, we receive certain commercial and development milestone payments, license revenues and a royalty of approximately 10% based on sales of AMPYRA/FAMPYRA by Acorda or its sub-licensee, Biogen Idec. This royalty payment may be reduced in any country based on lack of patent coverage, competing products achieving certain minimum sales thresholds, and whether Alkermes manufactures the product.

        Acorda has the right to terminate the license agreement upon 90 days' written notice. We have the right to terminate the license agreement for countries in which Acorda fails to launch a product within a specified time after obtaining the necessary regulatory approval or fails to file regulatory approvals within a commercially reasonable time after completion and receipt of positive data from all preclinical and clinical studies required for filing a marketing authorization application. If we terminate Acorda's license in any country, we are entitled to a license from Acorda of its patent rights and know-how relating to the product as well as the related data, information and regulatory files, and to market the product in the applicable country, subject to an initial payment equal to Acorda's cost of developing such data, information and regulatory files and to ongoing royalty payments to Acorda. Subject to the termination of the license agreement, licenses granted under the license agreement terminate on a country-by-country basis on the later of (i) September 2018 or (ii) the expiration of the last to expire of our patents or the existence of a threshold level of competition in the marketplace.

        Under our commercial manufacturing supply agreement with Acorda, we manufacture and supply AMPYRA/FAMPYRA for Acorda (and its sub-licensees). Under the terms of the agreement, Acorda may obtain up to 25% of its total annual requirements of product from a second source manufacturer. We receive royalties equal to 8% of net selling price for all product manufactured by us and a compensating payment for product manufactured and supplied by a third party. We may terminate the supply agreement upon 12 months' prior written notice to Acorda, and either party may terminate the supply agreement following a material and uncured breach of the supply or license agreement or the entry into bankruptcy or dissolution proceedings of the other party. In addition, subject to early termination of the supply agreement noted above, the supply agreement terminates upon the expiry or termination of the license agreement.

        In January 2011, we entered into a development and supplemental agreement to our amended and restated license agreement with Acorda. Under the terms of this agreement, we granted Acorda the right, either with us or with a third party, in each case in accordance with certain terms and conditions, to develop new formulations of dalfampridine or other aminopyridines. Under the terms of the agreement, Acorda has the right to select either a formulation developed by us or by a third party for commercialization. If Acorda selects and commercializes a formulation developed by us, we are entitled to development fees, milestone payments (for new indications if not previously paid), license revenues and royalties in accordance with our amended and restated license agreement, and either manufacturing fees as a percentage of net selling price for product manufactured by us or compensating fees for product manufactured by third parties. If Acorda selects a formulation not developed by us, then we will be entitled to various compensation payments and have the first option to manufacture such third-party formulation. The agreement expires upon the expiry or termination of the 2003 license agreement or may be earlier terminated by either party following an uncured breach of the agreement by the other party.

        Acorda's financial obligations under this development and supplemental agreement continue for a minimum of ten years from the first commercial sale of such new formulation, and may extend for a longer period of time, depending on the intellectual property rights protecting the formulation,

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regulatory exclusivity and/or the absence of significant market competition. These financial obligations survive termination.

Amylin

        In May 2000, we entered into a development and license agreement with Amylin for the development of exendin products falling within the scope of our patents, which includes the once-weekly formulation of exenatide, BYDUREON. Pursuant to the development and license agreement, Amylin has an exclusive, worldwide license to our polymer-based microsphere technology for the development and commercialization of injectable extended-release formulations of exendins and other related compounds. We receiv