Agios Pharmaceuticals : 2026 Proxy Statement (a7ac5c)

Published: 2026-04-29 12:32:12 ET AGIO

Published on 04/29/2026 at 12:32 pm EDT

Dear Stockholder:

88 Sidney Street, Cambridge, Massachusetts 02139

You are cordially invited to our Annual Meeting of Stockholders. The meeting will be a virtual meeting held via the internet on Thursday, June 18, 2026, beginning at 9:00 a.m., Eastern Time. The meeting will be held for the following purposes:

To elect each of the three Class I director nominees set forth in the Proxy Statement, each to serve for a three-year term expiring at the 2029 annual meeting of stockholders and until his or her respective successor is duly elected and qualified;

To vote, on an advisory basis, to approve the compensation paid to our named executive officers;

To approve an amendment to the Agios Pharmaceuticals, Inc. 2023 Stock Incentive Plan, as Amended, to increase the number of shares of common stock available thereunder by 2,000,000 shares;

To ratify the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2026; and

To transact such other business as may be properly brought before the meeting or any adjournment or postponement thereof.

Our Annual Meeting will be a virtual meeting of stockholders, which will be conducted exclusively via the internet at a virtual web conference. There will not be a physical meeting location, and stockholders will not be able to attend the Annual Meeting in person. This means that you can attend the Annual Meeting online, vote your shares during the online meeting and submit questions for consideration at the online meeting. Stockholders of record as of the close of business on April 21, 2026 are entitled to vote at the meeting. In order to attend the meeting online, vote your shares electronically during the meeting and submit questions, you must register in advance at https://www.proxydocs.com/AGIO prior to the deadline of June 16, 2026 at 5:00 p.m., Eastern Time. Upon completing your registration, you will receive further instructions via email, including your unique links that will allow you access to the meeting and will also permit you to submit questions. Please be sure to follow instructions found on your Notice of Internet Availability of Proxy Materials, proxy card and/or voting instruction form and subsequent instructions that will be delivered to you via email. We believe that hosting a "virtual meeting" will enable greater stockholder attendance and participation from any location around the world.

At Agios we are keenly focused on the contribution we can make to environmental sustainability. Instead of mailing a paper copy of our proxy materials to all of our stockholders, this year we are again providing access to our proxy materials over the internet under the U.S. Securities and Exchange Commission's "notice and access" rules. As a result, we are mailing to our stockholders a Notice of Internet Availability of Proxy Materials (the "Notice") instead of a paper copy of this Proxy Statement and our Annual Report for the fiscal year ended December 31, 2025 (the "2025 Annual Report"). We are mailing the Notice on or about April 24, 2026, and it contains instructions on how to access our proxy materials over the internet. The Notice also contains instructions on how each of our stockholders can receive a paper copy of our proxy materials, including this Proxy Statement, our 2025 Annual Report, and a form of proxy card. All stockholders who do not receive the Notice, including stockholders who have previously requested to receive paper copies of proxy materials, will receive a paper copy of the proxy materials by mail unless they have previously requested delivery of proxy materials electronically. We have chosen to employ this distribution process to conserve natural resources and reduce the costs of printing and distributing our proxy materials.

We encourage all stockholders to attend the Annual Meeting online. Whether or not you plan to attend the Annual Meeting online, we encourage you to read this Proxy Statement and submit your proxy or voting instructions as soon as possible by using the internet as described in the instructions included on your Notice, by calling the toll-free telephone number included in the Proxy Statement, or, if you received a paper copy of the proxy materials, by completing, signing, dating and returning your proxy card. Further information about how to register for the Annual Meeting, attend the Annual Meeting online, vote your shares and submit questions for consideration at the meeting is included in the accompanying Proxy Statement.

A complete list of registered stockholders will be available to stockholders of record for examination at https://www.proxydocs.com/AGIO during the 10-day period ending on the day before the Annual Meeting

Thank you for your ongoing support and continued interest in Agios Pharmaceuticals, Inc.

By Order of the Board of Directors,

Brian Goff

Chief Executive Officer

Cambridge, Massachusetts April 24, 2026

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting of Stockholders to be Held on June 18, 2026: This Proxy Statement and our 2025 Annual Report to Stockholders are available at www.proxydocs.com/AGIO. These documents are also available to any stockholder who wishes to receive a paper copy by calling (866) 648-8133, visiting www.investorelections.com/AGIO or emailing [email protected].

PROXY STATEMENT FOR THE 2026 ANNUAL MEETING OF STOCKHOLDERS ............... 1

GENERAL INFORMATION ABOUT THE ANNUAL MEETING AND VOTING .................. 1

STOCKHOLDERS SHARING THE SAME ADDRESS 10

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT 11

DELINQUENT SECTION 16(a) REPORTS 13

PROPOSAL 1: ELECTION OF DIRECTORS 14

CORPORATE GOVERNANCE 20

EXECUTIVE OFFICERS 38

EXECUTIVE COMPENSATION 40

CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS 83

PROPOSAL 2: ADVISORY VOTE ON EXECUTIVE COMPENSATION 85

PROPOSAL 3: APPROVAL OF AN AMENDMENT TO THE AGIOS PHARMACEUTICALS, INC.

2023 STOCK INCENTIVE PLAN, AS AMENDED 86

PROPOSAL 4: RATIFICATION OF SELECTION OF INDEPENDENT REGISTERED PUBLIC ACCOUNTANTS 104

STOCKHOLDER PROPOSALS 106

OTHER MATTERS 107

APPENDIX A - 2023 STOCK INCENTIVE PLAN, AS AMENDED ............................ A-1 APPENDIX B - AMENDMENT NO. 2 TO 2023 STOCK INCENTIVE PLAN, AS AMENDED ...... B-1

This Proxy Statement contains information about our 2026 Annual Meeting of Stockholders, or the Annual Meeting. The Annual Meeting will be held on Thursday, June 18, 2026, beginning at 9:00 a.m. Eastern Time. The meeting will be a virtual meeting held via the internet. In order to attend the Annual Meeting online, you must register in advance at https://www.proxydocs.com/AGIO prior to the deadline of June 16, 2026 at 5:00 p.m., Eastern Time. Upon completing your registration, you will receive further instructions via email, including your unique links that will allow you access to the meeting. Please be sure to follow instructions found on your Notice of Internet Availability of Proxy Materials, proxy card and/or voting instruction form and subsequent instructions that will be delivered to you via email. There will not be a physical meeting location, and stockholders will not be able to attend the Annual Meeting in person.

Except where the context otherwise requires, references to "Agios Pharmaceuticals," "Agios," "the company," "our company," "we," "us," "our" and similar terms refer to Agios Pharmaceuticals, Inc. and its consolidated subsidiaries. References to our website are inactive textual references only and the contents of our website are not incorporated by reference into this Proxy Statement.

This Proxy Statement and the enclosed proxy card are being furnished in connection with the solicitation of proxies by our board of directors for use at the Annual Meeting and at any adjournment of that meeting. All proxies will be voted in accordance with the instructions they contain. If you do not specify your voting instructions on your proxy, your shares will be voted in accordance with the recommendations of our board of directors. We are making this Proxy Statement, the related proxy card and our annual report to stockholders for the fiscal year ended December 31, 2025, or the 2025 Annual Report, available to stockholders for the first time on or about April 24, 2026.

We have made these proxy materials available to you because our board of directors is soliciting your proxy to vote at the Annual Meeting to be held on Thursday, June 18, 2026 at 9:00 a.m., Eastern Time, including at any adjournments or postponements of the meeting. As a holder of record of common stock as of the close of business on April 21, 2026, you are invited to attend the Annual Meeting online and are requested to vote on the items of business described in this Proxy Statement. This Proxy Statement includes information that we are required to provide to you under the rules adopted by the U.S. Securities and Exchange Commission, or the SEC, and that is designed to assist you in voting your shares.

Because we care about the sustainability of our environment, and in accordance with SEC rules, we have elected to provide access to our proxy materials, including this Proxy Statement and our 2025 Annual Report,

over the internet. Accordingly, we have sent a Notice of Internet Availability of Proxy Materials, or the Notice, to our stockholders of record entitled to vote at the Annual Meeting with instructions for accessing the proxy materials. We mailed the Notice on or about April 24, 2026 to all stockholders entitled to vote at the Annual Meeting.

All stockholders entitled to vote at the Annual Meeting will have the ability to access the proxy materials by visiting the website referred to in the Notice, www.proxydocs.com/AGIO. This makes the proxy distribution process more efficient and less costly and helps conserve natural resources. The Notice also contains instructions to request to receive, free of charge, a printed set of the proxy materials. You may request the printed set of proxy materials over the internet at www.investorelections.com/AGIO, by emailing [email protected], or by calling (866) 648-8133.

The Notice also identifies the date and time of the virtual Annual Meeting; instructions on how to attend the Annual Meeting online; the matters to be acted upon at the Annual Meeting and our board of directors' recommendation with regard to each matter; and information on how to access and vote the form of proxy.

No. The Notice identifies the items to be voted on at the Annual Meeting, but you cannot vote by marking the Notice and returning it. The Proxy Statement provides instructions on how to vote by proxy over the internet or by telephone, by requesting and returning a printed proxy card, or by voting online during the Annual Meeting.

If you receive more than one Notice, your shares may be registered in more than one name or in different accounts. Please follow the voting instructions on the Notices to ensure that all of your shares are voted.

At the Annual Meeting, stockholders will consider and vote on the following matters:

To elect each of the three Class I director nominees set forth in the Proxy Statement, each to serve for a three-year term expiring at the 2029 annual meeting of stockholders and until his or her respective successor is duly elected and qualified.

To vote, on an advisory basis, to approve the compensation paid to our named executive officers.

To approve an amendment to the Agios Pharmaceuticals, Inc. 2023 Stock Incentive Plan, as Amended, to increase the number of shares of common stock available thereunder by 2,000,000 shares.

To ratify the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2026.

Stockholders will also act on any other business that may properly come before the meeting, or any adjournment or postponement thereof.

Our 2026 Annual Meeting will be a virtual meeting of stockholders where stockholders will participate by accessing a website using the internet. There will not be a physical meeting location. We believe that hosting a virtual meeting facilitates greater stockholder attendance and participation by enabling stockholders to participate remotely from any location around the world. Our virtual meeting will be governed by our Rules of Conduct and Procedures which will be posted at https://www.proxydocs.com/AGIO in advance of the meeting. We have designed the virtual Annual Meeting to provide the same rights and opportunities to participate as stockholders have at an

in-person meeting, including the right to vote and ask questions through the virtual meeting platform.

We will host the Annual Meeting live online via webcast. In order to attend the Annual Meeting online, you must register in advance at https://www.proxydocs.com/AGIO prior to the deadline of June 16, 2026 at 5:00 p.m., Eastern Time. Online registration for the Annual Meeting will begin on or around April 24, 2026, and you should allow ample time for online registration. Upon completing your registration, you will receive further instructions via email, including your unique links that will allow you access to the meeting. Please be sure to follow instructions found on your Notice, proxy card and/or voting instruction form and subsequent instructions that will be delivered to you via email.

The webcast of the Annual Meeting will start at 9:00 a.m., Eastern Time, on June 18, 2026. We will have technicians standing by and ready to assist you with any technical difficulties you may have accessing the virtual meeting at 9:00 a.m., Eastern Time on June 18, 2026. If you encounter any difficulties accessing the virtual meeting during registration or at the time of the virtual meeting, please contact technical support by following the instructions provided to you upon registration for the Annual Meeting.

Only stockholders of record at the close of business on April 21, 2026, the record date for the Annual Meeting, are entitled to vote at the Annual Meeting. On this record date, there were 59,471,609 shares of our common stock outstanding. Common stock is our only class of stock outstanding.

Each share of our common stock that you own as of the record date, April 21, 2026, entitles you to one vote on each matter that is voted on.

Over the Internet prior to the Annual Meeting: To vote over the internet prior to the Annual Meeting, please go to the following website: www.proxypush.com/AGIO, and follow the instructions

at that site for submitting your proxy electronically. If you vote over the internet prior to the Annual Meeting, you do not need to complete and mail your proxy card or vote your proxy by telephone.

Your vote must be received by 8:59 a.m., Eastern Time, on June 18, 2026 to be counted.

Online during the Annual Meeting: In order to attend the Annual Meeting online and vote online during the Annual Meeting, you must register in advance at www.proxydocs.com/AGIO prior to the deadline of June 16, 2026 at 5:00 p.m., Eastern Time. You may vote your shares online while virtually attending the Annual Meeting by following instructions found on your Notice, proxy card and/or voting instruction form and subsequent instructions that will be delivered to you via email. If you vote by proxy prior to the Annual Meeting and choose to attend the Annual Meeting online, there is no need to vote again during the Annual Meeting unless you wish to change your vote.

If your shares are registered directly in your name, you may revoke your proxy and change your vote by following one of the below procedures:

Vote over the internet or by telephone as instructed above under "Over the Internet prior to the Annual Meeting" and "By Telephone prior to the Annual Meeting". Only your latest internet or telephone vote submitted prior to the Annual Meeting is counted. You may not change your vote prior to the Annual Meeting over the internet or by telephone after 8:59 a.m., Eastern Time, on June 18, 2026.

Sign, date and complete a new proxy card and send it by mail to Proxy Tabulator for Agios Pharmaceuticals, Inc., c/o Mediant, a BetaNXT business, P.O. Box 8016, Cary, NC 27512-9903. Mediant must receive the proxy card no later than June 17, 2026. Only your latest dated and timely received proxy will be counted.

Virtually attend the Annual Meeting and vote online as instructed above under "Online during the Annual Meeting". Virtually attending the Annual Meeting, without voting online during the Annual Meeting, will not revoke your internet vote, telephone vote or proxy submitted by mail, as the case may be.

If your shares are held in "street name," you may submit new voting instructions with a later date by contacting your bank, brokerage firm, or other nominee. You may also vote online during the Annual Meeting, which will have the effect of revoking any previously submitted voting instructions; see "How do I vote?" above.

A majority of our shares of common stock outstanding at the record date must be present virtually or represented by proxy to hold the Annual Meeting. This is called a quorum. For purposes of determining whether a quorum exists, we count as present any shares that are voted over the internet, by telephone, by completing and submitting a proxy by mail, or that are represented virtually at the Annual Meeting. Further, for purposes of establishing a quorum, we will count as present shares that a stockholder holds even if the stockholder votes to abstain or only votes on one of the proposals. In addition, we will count as present shares that are "broker

non-votes". If a quorum is not present, we expect to adjourn the Annual Meeting until we obtain a quorum.

The presence at the Annual Meeting, virtually or by proxy, of holders representing a majority of our outstanding common stock as of the record date, April 21, 2026, or approximately 29,735,805 shares, constitutes a quorum at the meeting and permits us to conduct the business of the meeting.

The three nominees for director to receive the highest number of votes FOR election will be elected as directors. This is called a plurality. Proposal 1 is not considered a discretionary matter. Therefore, if your shares are held by your brokerage firm in "street name" and you do not timely provide voting instructions with respect to your shares, your brokerage firm cannot vote your shares on Proposal 1. Broker non-votes will not be counted as votes FOR or WITHHELD from any nominee. As a result, such broker non-votes will have no effect on the voting on Proposal 1. You may:

vote FOR all nominees;

vote FOR a particular nominee or nominees and WITHHOLD your vote from the other nominees; or

WITHHOLD your vote from all nominees.

Votes that are withheld will not be included in the vote tally for the election of directors and will have no effect on the voting on Proposal 1.

To approve Proposal 2, holders of a majority of the votes cast on the matter must vote FOR the proposal.

Accordingly, abstentions and broker non-votes will have no effect on the outcome of this proposal. Proposal 2 is non-binding. Because this vote is advisory and not binding on us or our board of directors in any way, our board may decide that it is in our and our stockholders' best interests to compensate our named executive officers in an amount or manner that differs from that which is approved by our stockholders.

To approve Proposal 3, holders of a majority of the votes cast on the matter must vote FOR the proposal.

Accordingly, abstentions and broker non-votes will have no effect on the outcome of this proposal.

To approve Proposal 4, holders of a majority of the votes cast on the matter must vote FOR the proposal. Proposal 4 is considered a discretionary matter. If your shares are held by your brokerage firm in "street name" and you do not timely provide voting instructions with respect to your shares, your brokerage firm may vote your uninstructed shares on Proposal 4. If your brokerage firm exercises this discretionary authority, no broker non-votes are expected to occur in connection with Proposal 4. If you ABSTAIN from voting on Proposal 4, your shares will not be voted FOR or AGAINST the proposal and will also not be counted as votes cast or shares voting on the proposal. As a result, voting to ABSTAIN will have no effect on the outcome of Proposal 4.

Although stockholder approval of our audit committee's appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2026 is not required, we believe that it is advisable to give stockholders an opportunity to ratify this appointment. If this proposal is not approved at the Annual Meeting, our audit committee will reconsider its appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the year ending December 31, 2026.

Our board of directors recommends that you vote:

We do not know of any matters that may come before the Annual Meeting other than the election of our Class I directors, the approval, on an advisory basis, of the compensation of our named executive officers, the approval of an amendment to our 2023 Stock Incentive Plan, as Amended, and the ratification of the appointment of our independent registered public accounting firm. If any other matters are properly presented at the Annual Meeting, the persons named in the accompanying proxy intend to vote, or otherwise act, in accordance with their judgment on the matter.

The votes will be counted, tabulated and certified by Mediant, a BetaNXT business.

Your vote will be kept confidential and we will not disclose your vote, unless (1) we are required to do so by law (including in connection with the pursuit or defense of a legal or administrative action or proceeding), or

(2) there is a contested election for the board of directors. The inspector of election will forward any written comments that you make on the proxy card to management without providing your name, unless you expressly request disclosure on the proxy card.

If you wish to submit a question, on the day of the Annual Meeting, beginning at 8:00 a.m., Eastern Time on Thursday, June 18, 2026, you may log into the virtual meeting platform using the unique link provided to you

via email following the completion of your registration at www.proxydocs.com/AGIO, and follow the instructions there. Our virtual meeting will be governed by our Rules of Conduct and Procedures, which will be posted at www.proxydocs.com/AGIO in advance of the meeting. The Rules of Conduct and Procedures will govern the ability of stockholders to ask questions during the meeting, including rules on permissible topics, and rules for how questions and comments will be recognized and disclosed to meeting participants. All questions asked in accordance with the Rules of Conduct and Procedures received from stockholders before or during the virtual Annual Meeting will be posted on our website at investor.agios.com as soon as practicable following the Annual Meeting.

Preliminary voting results will be announced at the Annual Meeting. Final voting results will be tallied by the inspector of election and published in a current report on Form 8-K to be filed with the SEC within four business days after the Annual Meeting.

Stockholders wishing to suggest a candidate for director should write to our corporate secretary. In order to give the nominating and corporate governance committee sufficient time to evaluate a recommended candidate and/or include the candidate in our proxy statement for the 2027 annual meeting of stockholders, the recommendation should be received by our corporate secretary at our principal executive offices in accordance with our procedures detailed in the section below entitled "Stockholder Proposals." Such submissions must state the nominee's name, together with appropriate biographical information and background materials, and information with respect to the stockholder or group of stockholders making the recommendation, including the number of shares of common stock owned by such stockholder or group of stockholders, as well as other information required by our bylaws or SEC regulations. We may require any proposed nominee to furnish such other information as we may reasonably require in determining the eligibility of such proposed nominee to serve as an independent director or that could be material to a reasonable stockholder's understanding of the independence, or lack thereof, of such proposed nominee.

We will pay all of the costs of soliciting proxies. Our directors, officers and other employees may solicit proxies in person or by mail, telephone, fax or email. We will pay our directors, officers and other employees no additional compensation for these services. We will ask banks, brokerage firms and other nominees to forward these proxy materials to their principals and to obtain authority to execute proxies. We may reimburse them for their expenses.

All of our SEC filings are also available free of charge in the "Investors-Financials-SEC Filings" section of our website at https://www.agios.com.

If you have any questions about the Annual Meeting or your ownership of our common stock, please contact Investor Relations at 88 Sidney Street, Cambridge, Massachusetts 02139; telephone: 617-649-8600; e-mail: [email protected].

This proxy statement contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Such forward-looking statements include those regarding the potential benefits of PYRUKYND® (mitapivat), AQVESMETM (mitapivat) and tebapivat; the company's plans, strategies and expectations for its preclinical, clinical and commercial advancement of its drug development, including PYRUKYND®, AQVESMETM, tebapivat, AG-181 and AG-236; the company's strategic vision and goals; and the potential benefits of the company's strategic plans and focus. The words "aim," "anticipate," "believe," "could," "expect," "goal," "hope," "intend," "may," "might," "milestone," "plan," "potential," "possible," "strategy," "will," "vision," and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Such statements are subject to numerous important factors, risks and uncertainties that may cause actual events or results to differ materially from the company's current expectations and beliefs. For example, there can be no guarantee that any product candidate the company is developing will successfully commence or complete necessary preclinical and clinical development phases, that development of any of the company's product candidates will successfully continue or that any of the company's product candidates will receive marketing approval. There can be no guarantee that any positive developments in the company's business will result in stock price appreciation. Management's expectations and, therefore, any forward-looking statements in this proxy statement could also be affected by risks and uncertainties relating to a number of other important factors, including, without limitation: risks and uncertainties related to the company's ability to conduct its ongoing and planned research activities and its conduct ongoing and planned preclinical studies and clinical trials; the company's ability to obtain clinical supply of current or future drug candidates and commercial supply of current or future approved products; the company's ability to launch, market and sell current or future approved products; the company's results of clinical trials and preclinical studies, including subsequent analysis of existing data and new data received from ongoing and future trials and studies; the content and timing of decisions made by the U.S. Food and Drug Administration, the European Medicines Agency or other regulatory authorities, investigational review boards at clinical trial sites and publication review bodies; the company's ability to obtain and maintain requisite regulatory approvals and to enroll patients in its ongoing and planned clinical trials; unplanned cash requirements and expenditures; competitive factors; the company's ability to obtain, maintain and enforce patent and other intellectual property protection for any product candidates it is developing; the company's ability to establish and maintain key collaborations; and general economic and market conditions. These and other risks are described in greater detail under the caption "Risk Factors" included in the company's public filings with the SEC. Any forward-looking statements contained in this proxy statement speak only as of the date hereof, and the company expressly disclaims any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

The SEC has adopted rules that permit companies and intermediaries (e.g., brokers) to satisfy the delivery requirements for Notices and, if applicable, our annual report and other proxy materials, with respect to two or more stockholders sharing the same address by delivering a single Notice and, if applicable, a single set of our annual report and proxy materials, addressed to those stockholders. This practice, which is commonly referred to as "householding," potentially means extra convenience for stockholders and cost savings for companies.

This year, a number of brokers with account holders who are our stockholders will be "householding" our proxy materials. A single Notice and, if applicable, a single copy of our annual report and our proxy materials, will be delivered to multiple stockholders sharing an address unless contrary instructions have been received from the affected stockholders. Once you have received notice from your broker that they will be "householding" communications to your address, "householding" will continue until you are notified otherwise or until you revoke your consent.

If, at any time, you no longer wish to participate in "householding" and would prefer to receive a separate Notice and, if applicable, a separate set of our annual report and proxy materials in the future, please notify your broker or contact us. If you wish to receive a separate set of our annual report and proxy materials for this year's Annual Meeting, we will deliver them promptly upon written or oral request. Stockholders who currently receive multiple copies of the Notice, and, if applicable, our annual report and other proxy materials at their addresses and would like to request "householding" of their communications should contact their brokers or us. To contact us, direct your written or oral request to: Agios Pharmaceuticals, Inc., 88 Sidney Street, Cambridge, MA 02139, Attention: Corporate Secretary, 617-649-8600 or contact Investor Relations at 617-649-8600.

The following table sets forth information relating to the beneficial ownership of our common stock as of March 31, 2026, by:

each person known by us to beneficially own more than 5% of our outstanding shares of common stock;

each of our directors and nominees for director;

our principal executive officer, our principal financial officer and our other executive officers named in the Summary Compensation Table below, whom we collectively refer to as our named executive officers; and

all directors and executive officers as a group.

The percentage of shares beneficially owned is computed on the basis of 59,341,338 shares of our common stock outstanding as of March 31, 2026. The number of shares beneficially owned by each stockholder is determined under rules of the SEC. Under these rules, beneficial ownership includes any shares as to which the individual or entity has sole or shared voting power or investment power. In computing the number of shares beneficially owned by an individual or entity and the percentage ownership of that person, shares of common stock subject to options or other rights held by such person that are currently exercisable or will become exercisable within 60 days of March 31, 2026 are considered outstanding, although these shares are not considered outstanding for purposes of computing the percentage ownership of any other person. Unless otherwise indicated, the address of all listed stockholders is c/o Agios Pharmaceuticals, Inc., 88 Sidney Street, Cambridge, MA 02139. Each of the stockholders listed has sole voting and investment power with respect to the shares beneficially owned by the stockholder unless noted otherwise, subject to community property laws where applicable.

5% Stockholders

The Vanguard Group(1)

5,599,917

-

5,599,917

9.4%

Entities affiliated with Farallon Capital Partners, L.P. (2)

5,195,505

-

5,195,505

8.7%

BlackRock, Inc.(3)

4,513,170

-

4,513,170

7.6%

State Street Corporation(4)

3,108,145

-

3,108,145

5.2%

Armistice Capital, LLC(5)

3,036,000

-

3,036,000

5.1%

Named Executive Officers and Directors

James Burns

44,086

176,851

220,937

*

Sarah Gheuens, M.D., Ph.D.

74,406

115,507

189,913

*

Brian Goff

164,548

757,288

921,836

1.5%

Cecilia Jones

49,639

173,734

223,373

*

Krishnan Viswanadhan, Pharm.D.

5,141

28,839

33,980

*

Jacqualyn A. Fouse, Ph.D.

151,340

872,778

1,024,118

1.7%

Jay Backstrom, M.D., M.P.H.

-

-

-

*

Rahul Ballal, Ph.D.

12,414

46,306

58,720

*

Jeffrey Capello

6,073

35,966

42,039

*

Kaye Foster(6)

9,668

62,642

72,310

*

Maykin Ho, Ph.D.

17,032

107,642

124,674

*

Catherine Owen Adams

6,073

35,966

42,039

*

David Scadden, M.D.

17,603

113,242

130,845

*

Cynthia Smith

12,424

66,306

78,720

*

All executive officers and directors as a group

(15 persons)

612,028

2,753,476

3,365,504

5.4%

* Less than 1%.

Based solely on a Schedule 13G/A filed with the SEC on February 12, 2024. The Vanguard Group, or Vanguard, is deemed to be the beneficial owner of 5,599,917 shares of common stock, with respect to which it reported shared voting power over 38,887 shares, sole dispositive power over 5,497,393 shares and shared dispositive power over 102,524 shares. In the most recent Schedule 13G/A filed on March 26, 2026, the Vanguard Group subsequently reported that due to an internal realignment it no longer has, or is deemed to have, beneficial ownership over Company securities beneficially owned by various Vanguard subsidiaries and/or business divisions. The Vanguard Group also reported that certain subsidiaries or business divisions of subsidiaries of the Vanguard Group that formerly had, or were deemed to have, beneficial ownership with The Vanguard Group, will report beneficial ownership separately (on a disaggregated basis). The address of Vanguard is 100 Vanguard Blvd., Malvern, PA 19355.

Based solely on a Schedule 13G/A filed with the SEC on February 9, 2026 by Farallon Capital Partners,

L.P. and the following associated entities and persons: Farallon Capital Institutional Partners, L.P., Farallon Capital Institutional Partners II, L.P., Farallon Capital Institutional Partners III, L.P., Four Crossings Institutional Partners V, L.P., Farallon Capital Offshore Investors II, L.P., Farallon Capital F5 Master I, L.P., Farallon Capital (AM) Investors, L.P., Farallon Healthcare Partners Master, L.P., Farallon Partners, L.L.C., Farallon Institutional (GP) V, L.L.C., Farallon F5 (GP), L.L.C., Farallon Healthcare Partners (GP), L.L.C., Joshua J. Dapice, Philip D. Dreyfuss, Hannah E. Dunn, Varun N. Gehani, Nicolas Giauque, Avner A. Husen, David T. Kim, Michael G. Linn, Patrick (Cheng) Luo, Thomas G. Roberts, Jr., Edric C. Saito, Daniel S. Short, Andrew J. M. Spokes, John R. Warren, and Mark C. Wehrly, or collectively, the Farallon Reporting Persons, reporting beneficial ownership, consisting of shared voting power and shared dispositive power over these shares. The address of the Farallon Reporting Persons is c/o Farallon Capital Management, L.L.C., One Maritime Plaza, Suite 2100, San Francisco, California 94111.

Based solely on a Schedule 13G/A filed with the SEC on July 17, 2025 by BlackRock, Inc., or BlackRock, and certain of its subsidiaries. BlackRock is deemed to be the beneficial owner of 4,513,170 shares of common stock, with respect to which it reported sole voting power over 4,375,383 shares and sole dispositive power over 4,513,170 shares. The address of BlackRock is 50 Hudson Yards, New York, NY 10001.

Based solely on a Schedule 13G filed with the SEC on February 9, 2026. State Street Corporation, or State Street, is deemed to be the beneficial owner of 3,108,145 shares of common stock, with respect to which it reported shared voting power over 2,926,200 shares and shared dispositive power over 3,108,145 shares. The address of State Street Corporation is One Congress Street, Suite 1, Boston, Massachusetts 02114.

Based solely on a Schedule 13G filed with the SEC on February 17, 2026. The shares of common stock are held by Armistice Capital Master Fund Ltd., or Armistice Master Fund, and may be deemed to be beneficially owned by: (i) Armistice Capital, LLC, or Armistice Capital, as the investment manager of the Armistice Master Fund; and (ii) Steven Boyd, as the Managing Member of Armistice Capital. Armistice Capital LLC and Steven Boyd reported shared voting and dispositive power over the shares. The address of Armistice Capital is Armistice Capital, LLC, 510 Madison Avenue, 7th Floor, New York, NY 10022.

Includes shares of common stock held by the Foster Family Revocable Trust.

Under Section 16(a) of the Exchange Act, directors, executive officers, our principal accounting officer and beneficial owners of 10% or more of our common stock, or reporting persons, are required to report to the SEC on a timely basis the initiation of their status as a reporting person and any changes with respect to their beneficial ownership of our common stock. Based solely on our review of copies of such forms that we have received, or written representations from reporting persons, we believe that during the fiscal year ended December 31, 2025, all reporting persons complied with all applicable filing requirements, except with respect to a Form 4 filing by Dr. Scadden on July 15, 2025 to report the exercise of a stock option on July 10, 2025 and sale of shares on July 10, 2025, and a Form 4 filing by Theodore Washburn, our principal accounting officer, on February 5, 20245 to report the vesting of restricted stock units on February 1, 2025.

Our board of directors is divided into three classes, with one class of our directors standing for election each year. Directors in each class are elected at the annual meeting of stockholders held in the year in which the term for their class expires and hold office for a three-year term and until their resignation or removal or their successors are duly elected and qualified. In accordance with our certificate of incorporation and bylaws, our directors may fill existing vacancies on the board of directors.

The term of office of our Class I directors, Rahul Ballal, Ph.D., Brian Goff and Cynthia Smith, will expire at the Annual Meeting. The nominees for Class I directors for election at the Annual Meeting are Dr. Ballal,

Mr. Goff and Ms. Smith. If any of Dr. Ballal, Mr. Goff or Ms. Smith is elected at the Annual Meeting, such individual will be elected to serve for a three-year term that will expire at our 2029 annual meeting of stockholders and until such individual's successor is elected and qualified.

If no contrary indication is made, proxies in the accompanying form will be voted for Dr. Ballal, Mr. Goff and Ms. Smith or, in the event that any of Dr. Ballal, Mr. Goff or Ms. Smith is not a candidate or is unable to serve as a director at the time of the election (which is not currently expected), for any nominee who is designated by our board of directors to fill the vacancy.

Our priority in selection of board members is identification of members who will further the interests of our stockholders through their established record of professional accomplishment, the ability to contribute positively to the collaborative culture among board members, knowledge of our business, understanding of the competitive landscape and adherence to high ethical standards. Certain individual qualifications and skills of our directors that contribute to the board of directors' effectiveness as a whole are described in the following paragraphs.

The following paragraphs provide information as of the date of this Proxy Statement about each director and nominee for director, as furnished to us by the directors and nominees for director. The information presented includes information each such individual has given us about his or her age, all positions he or she holds, his or her principal occupation and business experience for the past five years, and the names of other publicly-held companies of which he or she currently serves as a director or has served as a director during the past five years. In addition to the information presented below regarding each such individual's specific experience, qualifications, attributes and skills that led our board of directors to the conclusion that he or she should serve as a director, we also believe that each of our directors and director nominees has a reputation for integrity, honesty and adherence to high ethical standards. Each has demonstrated business acumen and an ability to exercise sound judgment, as well as a commitment of service to our company and our board of directors.

Finally, we value their significant experience on other public company boards of directors and board committees.

Information about the number of shares of common stock beneficially owned by each of our directors and nominees for director appears above under the heading "Security Ownership of Certain Beneficial Owners and Management."

There are no family relationships between or among any of our executive officers, directors or nominees for director.

Rahul Ballal, Ph.D. 48 Director

Brian Goff 57 Chief Executive Officer and Director

Cynthia Smith 57 Director

Rahul Ballal, Ph.D. has served as a member of our board of directors since August 2022. Dr. Ballal has served as chief executive officer of Mediar Therapeutics Inc., or Mediar, a private biotechnology company, since March 2023. Prior to that, he served as President and Chief Executive Officer of Imara, Inc. or Imara, a publicly traded biotechnology company, from June 2018 until its merger with Enliven Therapeutics, Inc., or Enliven, in February 2023. Prior to joining Imara, Dr. Ballal served as Chief Business Officer of Northern Biologics Inc., a biotechnology company, from May 2016 to June 2018, and as an Entrepreneur-in-Residence at Versant Ventures Management LLC, a life sciences venture capital firm. Previously, Dr. Ballal was Vice President, Business Development at Flexion Therapeutics, Inc., or Flexion, a publicly traded biopharmaceutical company, from March 2011 to May 2016. Dr. Ballal serves on the boards of directors of Mediar and Enliven, and on the boards of directors of private biotechnology companies Vaderis Therapeutics AG and InduPro, Inc. Dr. Ballal received his Ph.D. in biochemistry and molecular biology from Georgetown University, his M.S. in bioinformatics from Johns Hopkins University and his B.A. in biology from Brown University. We believe Dr. Ballal is qualified to serve on our board of directors based on his broad experience in the life sciences industry, including in various investment, operating and leadership roles.

Brian Goff has served as our chief executive officer and a member of our board of directors since August 2022. Prior to joining Agios, Mr. Goff served as Executive Vice President, Chief Commercial and Global Operations Officer of Alexion Pharmaceuticals, Inc. or Alexion, from June 2017 to July 2021. Mr. Goff led the global commercial and operations teams at Alexion, which included responsibility for country operations in each of Alexion's affiliates in North America, EMEA, Japan, Asia Pacific, and Latin America. Prior to joining Alexion in June 2017, Mr. Goff was Chief Operating Officer and a member of the board of directors of Neurovance, Inc., a biopharmaceutical company, from December 2016 until its acquisition by Otsuka Pharmaceuticals Co., Ltd. in March 2017. Prior to joining Neurovance, Mr. Goff served as the Executive Vice President & President - Hematology Division of Baxalta Incorporated, a biopharmaceutical company, from January 2015 to July 2016 until its acquisition by Shire plc. He previously served with Baxter Healthcare Corporation as Global Hemophilia Franchise Head from June 2012 to December 2014. Earlier in his career,

Mr. Goff held positions of increasing responsibility in sales and marketing roles with Novartis Pharmaceuticals, and the pharmaceutical division of Johnson & Johnson. Mr. Goff currently serves on the board of directors and nominating and corporate governance committee and chairs the compensation and talent development committee of publicly traded biotechnology company Intellia Therapeutics, Inc. Mr. Goff has an M.B.A. from the Wharton School at the University of Pennsylvania and a B.A. from Skidmore College. We believe Mr. Goff is qualified to serve as a member of our board of directors due to his more than 30 years of industry experience, including executive commercial leadership experience in rare diseases and international operations.

Cynthia Smith has served as a member of our board of directors since August 2022. Since January 2017, Ms. Smith has consulted as a strategic advisor for biotechnology companies. Previously, she served as Chief Commercial Officer and a member of the Executive Committee of ZS Pharma, Inc., or ZS Pharma, a specialty pharmaceutical company developing therapies for treatment of hyperkalemia and liver diseases, from 2013 to 2016, where she led efforts to transition the company from a development stage company to a commercial enterprise. ZS Pharma was acquired by AstraZeneca in 2015. Prior to ZS Pharma, Ms. Smith served as Vice President, Market Access and Commercial Development at Affymax, Inc., a biopharmaceutical company, from

2008 to 2013. From 2000 to 2008, she held various senior leadership positions in market access, corporate strategy, government relations and external affairs at Merck & Co. Before beginning her career in the biopharmaceutical industry, Ms. Smith served as a healthcare policy analyst in the Office of Management and Budget at the White House from 1995 to 2000. Ms. Smith currently serves on the boards of directors of publicly traded biotechnology companies Akebia Therapeutics, Inc. Protara Therapeutics, Inc., Spero Therapeutics, Inc. and Tvardi Therapeutics, Inc., and on the board of directors of the French-American Foundation. Ms. Smith previously served on the board of directors of Nivalis Therapeutics, Inc. from November 2016 to July 2017 and on the board of directors of Dicerna Pharmaceuticals, Inc. from August 2018 until its acquisition by Novo Nordisk A/S in 2021. Ms. Smith earned a B.A. from the University of North Carolina at Chapel Hill, an M.B.A. from the Wharton School and an M.S. in public policy from the Eagleton Institute of Politics at Rutgers University. We believe that Ms. Smith is qualified to serve on our board of directors due to her more than two decades of broad leadership experience within the biopharmaceutical industry.

Kaye Foster 66 Director

Maykin Ho, Ph.D. 73 Director

Jeffrey Capello 61 Director

Catherine Owen Adams 55 Director

Kaye Foster has served as a member of our board of directors since December 2014. Ms. Foster has nearly 30 years of experience in human resources in the pharmaceutical industry and has been a Senior Advisor at the Boston Consulting Group since 2014 and in January 2022 joined ARCH Venture Partners as a venture partner. Previously, she was Senior Vice President, Global Human Resources at Onyx Pharmaceuticals, Inc., an Amgen, Inc., or Amgen, subsidiary and a biopharmaceutical company, or Onyx, from 2010 to 2014. At Onyx, which was acquired by Amgen in 2013, she led all aspects of human resources for U.S. and global operations. Prior to joining Onyx, Ms. Foster was Global Vice President of Human Resources and an Executive Committee member at Johnson and Johnson Corporation, a publicly traded healthcare company, from 2003 to 2010. Before Johnson and Johnson, Ms. Foster held several senior human resources executive positions with Pfizer Inc., a publicly traded pharmaceuticals company, supporting its pharmaceuticals businesses in Japan, Asia, Africa, Middle East and Latin America and, notably, led the integration of both the Warner-Lambert and Pharmacia mergers for these regions. Prior to that, she gained 10 years of operational experience within The Yellow Pages. She currently serves on the board of directors and compensation committee of Prime Medicine, Inc., a publicly traded biotechnology company, on the board of directors and compensation and community equity committee of National Resilience Inc., a technology-focused biomanufacturing company, on the board of directors and compensation committee of Xaira Therapeutics, a private biotechnology company, and on the board and human resources committee of Spelman College. Ms. Foster formerly served on the Board of Trustees of the Glide Foundation, on the board of directors and compensation committee of Grail, Inc., or Grail, a private biotechnology company, prior to its acquisition by Illumina, Inc., or Illumina, and on the board of directors and compensation and facilities committees of Stanford Health Care, a hospital and healthcare system. She earned her undergraduate degree at Baruch College of the City University of New York and received her M.B.A. from Columbia University, Graduate School of Business. We believe Ms. Foster's qualifications to serve on our board of directors include her extensive experience as an executive in the pharmaceuticals industry, including her experience in people management, compensation planning and driving and maintaining corporate culture.

Maykin Ho, Ph.D. has served as a member of our board of directors since June 2015. Dr. Ho has more than 30 years of experience in the healthcare and finance industries. She was a venture partner at Qiming Venture Partners, a venture capital firm in China and Hong Kong, for ten years untilJuly 2025. From July 1992 to February 2015, she held various positions at Goldman Sachs, a global investment bank, including: from 2010 to 2015, she served as advisory director of global healthcare investment banking; from 2002 to 2010, she served as partner and co-head of healthcare investment research; and from 1992 to 2010 she served as senior biotechnology research analyst. Prior to Goldman Sachs, Dr. Ho held various managerial positions at DuPont-Merck Pharmaceuticals, a global pharmaceutical company, and DuPont de Nemours & Company. She is a member of the board of directors of BioMarin Pharmaceutical Inc., a publicly traded biopharmaceutical company; Kyntra Bio, Inc. (formerly Fibrogen, Inc.), a publicly traded biotechnology company; Neumora Therapeutics, Inc., a public biotechnology company; Parexel International, a privately-held, global pharmaceutical services company; and Pelage Pharmaceuticals, a private biotechnology company of. Dr. Ho also serves on the board of directors of two non-profit research institutes: the Aaron Diamond AIDS Research Center and the Institute for Protein Innovation. In addition, she is a member of the Biotech Advisory Panel of The Stock Exchange of Hong Kong.

Previously, Dr. Ho served on the board of directors of Grail prior to its acquisition by Illumina in 2021;and Parexel International when it was a publicly traded company. She was also a member of the investment committee of the Society of Neuroscience. She was a postdoctoral fellow at the pathology department of Harvard Medical School and a graduate of the Advanced Management Program at The Fuqua School of Business, Duke University. Dr. Ho received a Ph.D. in microbiology and immunology and a B.S. from the State University of New York, Downstate Medical Center. We believe Dr. Ho is qualified to serve on our board of directors due to her extensive experience in healthcare investment research and banking.

Jeffrey Capello has served on our board of directors since June 2023. Mr. Capello has served as the managing partner of Monomoy Advisors, a financial advisory firm, since April 2021. Mr. Capello served as the Executive Vice President and Chief Financial Officer of Biogen Inc, a biopharmaceutical company, from December 2017 to August 2020. Prior to joining Biogen, Mr. Capello served as the Chief Financial Officer of Beacon Health Options, Inc., a behavioral health company, with responsibility for finance, human resources, information technology, real estate and procurement from October 2016 until November 2017. From July 2015 until September 2016, Mr. Capello was the founder and Chief Executive Officer of Monomoy Advisors. From July 2014 until June 2015 Mr. Capello served as the Executive Vice President and Chief Financial Officer of Ortho-Clinical Diagnostics, an in-vitro diagnostics company that was acquired by the Carlyle Group from Johnson & Johnson, with responsibility for global finance and business development. From March 2010 to December 2013 Mr. Capello served as Chief Financial Officer and Executive Vice President of Boston Scientific Corporation, a medical device company. Mr. Capello joined Boston Scientific in June 2008 and served as Senior Vice President and Chief Accounting Officer until March 2010. From 2006 to 2008 he was the Senior Vice President and Chief Financial Officer with responsibilities for global finance and business development at PerkinElmer, Inc., a life sciences tool company. Previously, he served as PerkinElmer's Vice President of Finance, Corporate Controller, Treasurer and Chief Accounting Officer from 2001 to 2006. Prior to his tenure at PerkinElmer, Mr. Capello was a Partner at PricewaterhouseCoopers LLP, both in the United States and in the Netherlands. Mr. Capello serves on the board of directors of Neogen Corporation, a publicly traded company that develops solutions for food and animal safety, and previously served on the boards of directors and chaired the audit committees of public biotechnology companies Sirtis Pharmaceuticals, Inc., OvaScience, Inc. and Flex Pharma, Inc. Mr. Capello holds a M.B.A. from Harvard Business School and a B.S. in Business Administration from the University of Vermont. We believe that Mr. Capello is qualified to serve on our board of directors due to his over 30 years of industry experience, including extensive experience as a senior finance executive.

Catherine Owen Adams has served as a member of our board of directors since June 2023. Ms. Owen Adams has served as Chief Executive Officer and as a member of the board of directors of Acadia Pharmaceuticals Inc. since September 2024. Prior to that, Ms. Owen Adams was Senior Vice President, Major Markets at Bristol-Myers Squibb, or BMS, a global biopharmaceutical company, overseeing commercial operations for the business in 18 countries including Japan, Germany, France, and others across Europe.

Ms. Owen Adams joined BMS in 2019 from Johnson & Johnson Corporation, or J&J, a healthcare company, where she served as President of Janssen Immunology North America from 2018 to 2019, which launched new products in Crohn's disease and psoriasis and led the development of J&J's biosimilars strategy. Prior to leading Janssen Immunology, Ms. Owen Adams was the President of the Infectious Diseases business in the US from 2016 to 2018, responsible for the HIV, RSV, Flu, and Hepatitis B pipeline. Prior to that Ms. Owen Adams worked in various functions and businesses at J&J and led the launches of multiple products in both Europe and the United States. Ms. Owen Adams began her career in the pharmaceutical industry in 1992 at AstraZeneca in London as a production support pharmacist. Ms. Owen Adams currently serves on the board of directors of AssistRx, a privately held company. Ms. Owen Adams was formerly on the board of directors and chair of the compensation committee for Optinose PLC, a public specialty pharmaceutical company, and was on the board of directors of Robert Wood Johnson University Hospitals, a non-profit organization. Ms. Owen Adams earned her Bachelor of Science degree in pharmacy from the University of Manchester and completed her registered pharmacy degree and was a member of the Royal Pharmaceutical Society of Great Britain, MRPhs. We believe that Ms. Owen Adams is qualified to serve on our board of directors because of her extensive commercial experience in the biotechnology industry.

Jacqualyn A. Fouse, Ph.D. 64 Chair

David Scadden, M.D. 73 Director

Jay Backstrom, M.D., M.P.H. 71 Director

Jacqualyn A. Fouse, Ph.D. served as our chief executive officer from February 2019 to August 2022, and has served as a member of our board of directors since December 2017. Dr. Fouse has served as the chair of our board of directors since August 2022. Dr. Fouse served as executive chair of Dermavant Sciences, Inc., a biopharmaceutical company, from July 2017 until September 2018. From September 2010 until June 2017,

Dr. Fouse served in various capacities at Celgene Corporation, a biopharmaceutical company, or Celgene, serving as strategic advisor to the management executive committee from April 2017 to June 2017, president and chief operating officer from March 2016 to March 2017, president, hematology and oncology from August 2014 to February 2016, executive vice president and chief financial officer from February 2012 to July 2014, and senior vice president and chief financial officer from September 2010 to February 2012. Prior to joining Celgene, Dr. Fouse served as chief financial officer of Bunge Limited, or Bunge, a global agribusiness and food company, from 2007 to 2010. Prior to joining Bunge, Dr. Fouse served as senior vice president, chief financial officer and corporate strategy at Alcon Laboratories, Inc., or Alcon, a global medical company, from 2006 to 2007, and as its senior vice president and chief financial officer from 2002 to 2006. Prior to her time with Alcon she held a variety of senior leadership roles with international companies. Dr. Fouse is also a director and member of the audit and finance committee and nominating and corporate governance committee of Incyte Corporation, and a director and member of the audit committee, the nominating and governance committee and the compensation committee of Madrigal Pharmaceuticals, Inc., a publicly traded biopharmaceutical company, and was a director of Perrigo Company, a publicly traded pharmaceutical manufacturer, Celgene and Dick's Sporting Goods, Inc., a publicly traded sporting goods retailer. Dr. Fouse also serves on the board of directors, and as Treasurer and member of the finance committee, of the non-profit organization Friends of Herring River and on the Northeast Chapter board and executive committee, and as Treasurer, of the non-profit organization the Society for Ecological Restoration. Dr. Fouse earned a B.A. and an M.A. in Economics and a Ph.D. in Finance from the University of Texas at Arlington. She also earned a Masters in Environmental Management from the Yale University School of Forestry and Environmental Studies and a Masters in Wildlife Forensics and Conservation from the University of Florida. We believe Dr. Fouse is qualified to serve as a member of our board of directors due to her extensive experience in the biotechnology sector and her international and senior leadership experience.

David Scadden, M.D. has served as a member of our board of directors since May 2017. Dr. Scadden is a hematologist/oncologist and physician-scientist. He is the Gerald and Darlene Jordan Professor of Medicine at Harvard University, a position he has held since 2006. Since 1995, Dr. Scadden has practiced at the Massachusetts General Hospital, where he founded and directs the Center for Regenerative Medicine and directed the Hematologic Malignancies Center of the MGH Cancer Center for 10 years. Dr. Scadden co-founded and co-directs the Harvard Stem Cell Institute and is Chairman emeritus and Professor of the Harvard University Department of Stem Cell and Regenerative Biology. He is a member of the National Academy of Medicine, the American Academy of Arts and Sciences, is an affiliate member of the Broad Institute of Harvard and MIT and is a former member of the Board of External Experts for the National Heart, Lung and Blood Institute, the Board of Scientific Counselors for the National Cancer Institute, Board of Directors of the International Society for Stem Cell Research and the Executive Committee of the American Society of Hematology. Dr. Scadden is on the board of directors and organization, leadership and compensation committee of Editas Medicine, Inc., a publicly traded biotechnology company, and on the board of directors of the private biotechnology company Lightning Biotherapeutics. Dr. Scadden is also a scientific founder of Fate Therapeutics, Inc., a publicly traded biotechnology company, and was a scientific founder and member of the board of directors and scientific advisory board of Magenta Therapeutics, a publicly traded biotechnology company now merged with Dianthus Therapeutics, Inc. Dr. Scadden was also formerly on the board of directors and science committee of Carisma Therapeutics Inc., a publicly traded biotechnology company, and on the boards of directors of the private biotechnology companies LifeVault Bio, Sonata Therapeutics and Clear Creek Bio, Inc. He is the recipient of numerous honors including the E. Donnall Thomas and the Dameshek awards from the American Society of Hematology and awards from the Doris Duke Charitable Trust, the Ellison Medical Foundation, the Burroughs Welcome Fund, and the Leukemia and Lymphoma Society. Dr. Scadden holds degrees from Bucknell University, Case Western Reserve University and honorary degrees from Harvard University, Bucknell University, Case Western Reserve University and Lund University in Sweden. We believe Dr. Scadden is qualified to serve on our board of directors due to his scientific expertise in the field of hematology.

Jay Backstrom, M.D., M.P.H. has served as a member of our board of directors since July 2025.

Dr. Backstrom is Chief Executive Officer and President of Kamino Therapeutics, Inc. and previously served as a director and President and Chief Executive Officer of Scholar Rock Holding Corporation, or Scholar Rock, from September 2022 to April 2025. Prior to joining Scholar Rock, from December 2019 to December 2021,

Dr. Backstrom served as Executive Vice President, Research and Development at Acceleron Pharma, which was acquired by Merck in 2021. Dr. Backstrom previously served as Chief Medical Officer of Celgene Corporation from April 2016 to December 2019, having served in other roles at Celgene from March 2008 to March 2016.

Dr. Backstrom is a member of the Board of Directors of Be BioPharma, Inc. Dr. Backstrom previously served as a director of Lava Therapeutics N.V., Disc Medicine, Inc. and Autolus Therapeutics PLC. Dr. Backstrom earned his M.D. from Temple University School of Medicine, and holds an M.P.H. From St. Louis University School of Public Health. Our Board of Directors believes that Dr. Backstrom's extensive scientific experience and his leadership skills qualify him to serve on our Board of Directors. We believe Dr. Backstrom is qualified to serve on our board of directors due to his extensive scientific experience and leadership skills.

We believe that good corporate governance is important to ensure that Agios is managed for the longterm benefit of our stockholders. This section describes key corporate governance practices that we have adopted. We have adopted a code of business conduct and ethics, which applies to all of our officers, directors and employees, corporate governance guidelines and charters for our audit committee, our compensation & people committee, our nominating and corporate governance committee and our science and technology committee.

We have posted copies of our code of business conduct and ethics and corporate governance guidelines, as well as each of our committee charters, on the Corporate Governance page of the Investors section of our website, https://www.agios.com, which you can access free of charge. Information contained on the website is not incorporated by reference in, or considered part of, this Proxy Statement. We intend to disclose on our website any amendments to, or waivers from, our code of business conduct and ethics that are required to be disclosed by law or Nasdaq listing standards. We will also provide copies of these documents, as well as our other corporate governance documents, free of charge, to any stockholder upon written request to Investor Relations, at

88 Sidney Street, Cambridge, Massachusetts 02139; telephone: 617-649-8600; e-mail: [email protected].

Our board of directors has adopted corporate governance guidelines to assist in the exercise of its duties and responsibilities and to serve the best interests of Agios and our stockholders. These guidelines, which provide a framework for the conduct of our board's business, provide that:

our board's principal responsibility is to oversee the management of Agios;

a majority of the members of our board shall be independent directors;

the independent directors meet regularly in executive session;

directors have full and free access to management and, as necessary and appropriate, independent advisors;

new directors participate in an orientation program and all directors are expected to participate in continuing director education on an ongoing basis; and

our board and its committees conduct a self-evaluation annually to determine whether they are functioning effectively.

We are committed to building a sustainable business that provides long-term value for all our stakeholders. Central to our mission is our drive to improve the lives of patients with life-threatening and life-altering rare diseases, including those communities that have, until now, been underserved. We also support and advance a range of other responsibilities, such as: increasing access to medicines; furthering knowledge of rare conditions; promoting principles of inclusion inside and outside of the company; building a strong culture of flexibility and respect; supporting health equity; reducing our waste and energy usage; making a difference in our communities; and conducting our business according to the highest ethical standards.

Since 2020, we have published our Environmental, Social, and Governance, or ESG, Report, with the intent of disclosing relevant ESG initiatives and metrics from across the company that are aligned not only with

our values and our culture, but also with the United Nations Sustainable Development Goals and the standards for the Biotechnology and Pharmaceuticals industry set by the Sustainability Accounting Standards Board, now part of the International Financial Reporting Standards (IFRS). Our 2026 ESG Report is available on our website, https://www.agios.com, under the "Corporate Governance" section. The contents of the ESG Report are not deemed to be part of this proxy statement or incorporated by reference herein.

Our ESG program is centered around our commitments to the patients we serve, our employees, our communities and world, and business ethics and values.

Our Commitment to Patients

Advancing Science

We are focused on making a difference for patients with rare diseases by discovering, developing, and delivering innovative medicines. Our pioneering research in pyruvate kinase (PK) activation led to the development of mitapivat, the first and only approved therapy for PK deficiency and the first and only treatment approved for all subtypes of thalassemia, regardless of genotype or transfusion burden. Mitapivat is approved as PYRUKYND® for adults with PK deficiency in both the U.S. and Europe. The medicine is also approved for adults with thalassemia in Saudi Arabia and the United Arab Emirates under the brand name PYRUKYND®, as well as in the U.S. under the brand name AQVESME™.

In addition, our robust pipeline spans late-, mid-, and early-stage programs targeting several rare diseases, including sickle cell disease (SCD), lower-risk myelodysplastic syndromes, phenylketonuria, and polycythemia vera.

Improving Care for Underserved Communities

In addition to developing and delivering medicines for these rare disease communities, we also support and partner with them to advance understanding, education, and care.

In PK deficiency, we have made significant progress in understanding the burden of this disease by funding a natural history study and establishing the first global patient registry. Additionally, we have developed educational resources for physicians and patients and partnered with patient advocacy groups to create the first international PK deficiency Patient Advisory Council-a multidisciplinary team that includes patients, caregivers, advocates, and physicians.

We have taken a similar approach to supporting the thalassemia community, fostering meaningful connections among physicians, patients, caregivers, and industry stakeholders. One key initiative is the formation of the Thalassemia Advocacy Advisory Council (AAC), which was established to provide strategic insights and ensure that Agios' thalassemia efforts deliver real value to those impacted by the disease. In 2024, the AAC launched the Global Thalassemia Health Literacy Survey, an initiative that is now informing the development of peer-to-peer educational programs that address critical knowledge gaps, strengthen patient empowerment, and promote informed decision-making in care. Additionally, Agios established the Alpha Beta Revolution Patient Council, a community of thalassemia patients, caregivers, and healthcare providers that advises us on what it means to feel seen and supported when living with or caring for someone with thalassemia, including communication with care teams, access to resources, and opportunities to better connect with more patients.

In SCD, we reported topline results from the RISE UP Phase 3 trial of mitapivat in patients aged 16 years or older at the end of 2025. Based on the clinically meaningful benefits observed in the RISE UP clinical program, we announced in March 2026 that we will pursue U.S. accelerated approval for mitapivat in SCD -

the U.S. Food and Drug Administration's (FDA) pathway that expedites the availability of medicines that can fill a medical need for a serious condition. We collaborated closely with the SCD community to design the RISE UP clinical program and drive awareness of it. Building trust in clinical research is critical, particularly within the sickle cell community, where historical inequities and racial bias have contributed to skepticism toward the medical establishment. We prioritized patient voices from the outset of our clinical trial planning, co-designing key aspects of the clinical program and shaped communications strategies with the community to enhance trial awareness and recruitment - an invaluable approach we are now applying across our other clinical programs.

Beyond this program, we partner closely with the SCD community on educational initiatives and attend and sponsor conferences supporting this community throughout the year.

Recognizing the shared challenges and experiences of these patient communities, Agios launched the Red Cell Revolution - a multi-stakeholder advocacy advisory council focused on hemolytic anemias, including SCD, thalassemia, and PK deficiency. The council comprises 20 individuals, including patients, caregivers, healthcare professionals, and representatives from Agios. United by a common vision, the council aims to foster a global community where individuals living with these under-recognized, lifelong hemolytic anemias - and their allies - can amplify their voices and drive meaningful change.

Beyond these initiatives and our clinical programs, we partner with clinicians and researchers to help close persistent knowledge gaps in rare diseases through clinical fellowship research grants, investigator-sponsored trials, and medical education grants.

Access to Medicines

Prior to the U.S. commercial launch of PYRUKYND® for PK deficiency, we developed a philosophy and guiding principles to inform all of our pricing and access decisions. We collaborated closely with the patient, caregiver, and physician communities to develop myAgios Patient Support Services to help ensure that as many eligible patients as possible can access to our medicines and that out-of-pocket costs for individual patients are as reasonable as possible. Since FDA approval, 86% of eligible U.S. patients with commercial health insurance have utilized the PYRUKYND® Copay Program, which lowers copay costs to $0 per prescription. Our Patient Assistance Program offers free prescriptions for eligible U.S. patients who are uninsured, underinsured or rendered uninsured to help them get access to our medicines. The programs established for PYRUKYND® in the

U.S. are also being extended to AQVESME™ for adults living with thalassemia.

Additionally, our Global Managed Access Program offers a pathway for patients to obtain access to Agios' medicines provided they meet the defined criteria and reside in a country where access is permissible under local laws and regulations. Healthcare providers may submit an inquiry on behalf of their patients to Agios for consideration.

Patient Safety

We place a high priority on patient safety through adhering to all relevant best practices and regulations in clinical trials, product manufacturing and supply chain management.

Our Commitment to Our Employees

Our Culture

Agios offers a supportive, engaging, and flexible environment that empowers people to bring their whole selves to work and motivates them to make a positive impact for patients with rare diseases. We intentionally cultivate a culture of flexibility, psychological safety, and deliberate development. We regularly ask our people

about their experiences at Agios and what we can do to improve our programs and environment through a full organizational health survey, conducted every 2 to 3 years, as well as more frequent, targeted pulse surveys. We eagerly listen to our team's feedback, analyze what we hear, and use the findings to make informed decisions that continue to make Agios a great place to work.

Deliberate Development

We focus on retaining and hiring people who care deeply about our mission, about each other, and about the people who count on us. Our retention strategy is fueled by our focus on the deliberate development of all employees through programs such as tuition reimbursement, 'lunch and learn' sessions, our DevelOPPortunities Program - which offers temporary, part time assignments that provide employees with an opportunity to build new, differentiated skill sets while maintaining their current role - and encouraging internal promotions and cross-functional internal moves when aligned with employee career interest.

Flexibility

Agios' approach to workplace flexibility is foundational to our culture. We offer all location-agnostic team members (i.e., those who are not based in a lab, the field, or our headquarters office) the option to choose where they work: fully remote, fully in the office, or hybrid. By embracing flexibility, we foster a culture that promotes different work perspectives, work styles, health and wellness needs, care of families, and productivity.

As with every significant people-related decision at Agios, our approach to workplace flexibility is data-driven and informed by employee input and feedback. Our surveys help us gauge the effectiveness of our approach and tailor it as needed. To date, the feedback has been overwhelmingly positive.

Flexibility and remote work open the doors to hiring the best talent for each role, regardless of physical location. Individuals with different experiences, based in different locations, and with various backgrounds can join Agios and contribute to our mission, while striving for better integration between work and well-being. In 2025, approximately 85% of our new hires chose to work remotely.

Compensation and Benefits

We offer a competitive and balanced compensation and benefits package, including equity for employees with flexibility to select the percentage of restricted stock units versus stock options, discretionary paid time off policy, generous parental and family leave plans, and premium medical benefits. The benefits that have evolved as a direct result of employee feedback include: medical plan designs and carrier, discretionary time off policy, two week-long company shutdowns per year, subsidized back-up child care, a sabbatical program, and an inclusive family forming benefit.

Recruitment

Identifying and recruiting top talent is critical to our growing organization. To do so, we leverage internal networks and a variety of external resources such as professional organizations, academic institutions, career sites, job fairs, and industry conferences. We value differences in the talent we recruit to ensure continued growth in new ways of thinking and innovation across teams.

Valuing Differences

As we continue our work in rare diseases that affect a broad range of individuals, we believe a workforce with a variety of representative, cognitive, and experiential differences enables us to better understand and

develop treatments for these diverse patient populations. A commitment to valuing differences is an ongoing journey; we recognize there is always more to do. We strive to ensure our efforts are having a real impact on our teams, our communities, and the patients we serve.

Our Commitment to Our Communities and the World

We are committed to supporting and connecting with our communities and to doing our part to support a cleaner, healthier planet.

Community Relations

We have organized our community relations initiatives around three pillars: (1) complementing our pursuit of innovative medicines by meeting non-therapeutic needs for patient communities, (2) opening doors to STEM education and careers, and (3) being a good neighbor and helping to meet the fundamental needs of those around us. We maintain a corporate giving program that identifies initiatives to support our community and creates opportunities for employee involvement in causes that benefit our community.

Environmental Initiatives

Although all of our buildings are leased to us, we remain committed to advancing and promoting sustainable practices within our current spaces, while ensuring that future spaces are designed with sustainability in mind. To date, we have implemented a number of initiatives, including product take-back programs, cold storage upgrades, equipment donation efforts, and waste minimization strategies. In addition, we have established practices aimed at reducing hazardous waste, minimizing solid waste production, and conserving water.

Agios launched numerous environmental sustainability initiatives in 2025, most notably including a safety glass recycling program, prescription eyeglass and safety glass program, introduction of fume hood sash height awareness signage, My Green Lab topic of the month education series, and creation of a Green Chemistry resources hub. Agios also expanded existing sustainability initiatives, including updated waste auditing of hazardous and non-regulated waste streams in 2025.

Our Commitment to Ethics and Values

At Agios, we are committed to conducting business ethically, responsibly, and transparently. We hold ourselves to the highest standards and have built strong governance practices to ensure accountability for our actions. This includes a Code of Business Conduct and Ethics, which applies to all of our officers, directors, and employees; corporate governance guidelines adopted by our board of directors; and charters for our audit committee, compensation & people committee, nominating and corporate governance committee, and science and technology committee. In addition, we have robust policies in place to ensure compliant interactions with healthcare providers, protection of personal and patient data, and strong cybersecurity practices, among others.

Rule 5605 of the Nasdaq Listing Rules requires a majority of a listed company's board of directors to be comprised of independent directors. In addition, the Nasdaq Listing Rules require that, subject to specified exceptions, each member of a listed company's audit, compensation and nominating and corporate governance committees be independent, that audit committee members also satisfy independence criteria set forth in

Rule 10A-3 under the Securities Exchange Act of 1934, as amended, or the Exchange Act and that compensation committee members also satisfy the independence criteria set forth in Rule 10C-1 under the Exchange Act.

Under Rule 5605(a)(2) of the Nasdaq Listing Rules, a director will only qualify as an "independent director" if, in the opinion of a company's board of directors, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In order to be considered independent for purposes of Rule 10A-3 of the Exchange Act, a member of an audit committee of a listed company may not, other than in their capacity as a member of the audit committee, the board of directors, or any other board committee, accept, directly or indirectly, any consulting, advisory, or other compensatory fee from the listed company or any of its subsidiaries or otherwise be an affiliated person of the listed company or any of its subsidiaries.

In addition, in affirmatively determining the independence of any director who will serve on a company's compensation committee, Rule 10C-1 under the Exchange Act requires that a company's board of directors consider all factors specifically relevant to determining whether a director has a relationship to such company which is material to that director's ability to be independent from management in connection with the duties of a compensation committee member, including, but not limited to: (i) the source of compensation of the director, including any consulting advisory or other compensatory fee paid by such company to the director; and

whether the director is affiliated with the company or any of its subsidiaries or affiliates.

In March 2026, our board of directors reviewed the composition of our board of directors and its committees and the independence of each director. Based upon information requested from and provided by each director concerning his or her background, employment and affiliations, including family relationships, our board of directors has determined that each of our directors is an "independent director" as defined under

Rule 5605(a)(2) of the Nasdaq Listing Rules, with the exception of Mr. Goff, our chief executive officer. Our board of directors had also previously determined in March 2024 that David P. Schenkein, a former director who resigned from our board of directors in February 2025, was an "independent director" as defined under

Rule 5605(a)(2). In addition, our board of directors determined that Dr. Ballal, Mr. Capello and Dr. Ho, who currently comprise our audit committee, Ms. Foster, Ms. Owen Adams and Ms. Smith, who currently comprise our compensation & people committee, and Ms. Foster, Dr. Ho and Dr. Scadden, who currently comprise our nominating and corporate governance committee, satisfy the independence standards for such committees established by the SEC and the Nasdaq Listing Rules, as applicable. In making such determinations, our board of directors considered the relationships that each such non-employee director has with our company, including any relevant transactions described below in "Certain Relationships and Related Party Transactions" and the beneficial ownership of our capital stock by each non-employee director, as well as all other facts and circumstances our board of directors deemed relevant in determining independence. Mr. Goff is not independent because he is our chief executive officer.

Our corporate governance guidelines provide that the nominating and corporate governance committee shall periodically assess our board of directors' leadership structure, including whether the offices of chief executive officer and chair of the board of directors should be separate and why the board of directors' leadership structure is appropriate given the specific characteristics or circumstances of our company. These guidelines provide the board of directors with flexibility to determine whether the two roles should be combined or separated based upon our needs and the board of directors' assessment of its leadership from time to time. We currently separate the roles of chief executive officer and chair of the board of directors. Separating the duties of the chair of the board from the duties of the chief executive officer allows our chief executive officer to focus on our day-to-day business, while allowing the chair of the board to lead the board of directors in its fundamental role of providing advice to and independent oversight of management. Specifically, the chair of our board of directors presides over meetings of the board of directors, facilitates communications between management and the board of directors, provides input on the design of the board of directors and assists with other corporate governance matters. We also have a lead director, Ms. Foster, whose duties include, as needed, the following:

Chairing any meeting of the independent directors in executive session;

Meeting with any director who is not adequately performing his or her duties as a member of our board of directors or any committee; however, each director is free to communicate directly with the chair of the board of directors and with the chief executive officer;

Facilitating communications between other members of our board of directors, our chair and our chief executive officer;

Working with our chair and our chief executive officer in the preparation of the agenda for each board meeting and in determining the need for special meetings of our board of directors;

Monitoring, with the assistance of our Corporate Secretary, or his designee, communications from stockholders and other interested parties and providing copies or summaries to the other directors as she considers appropriate (see "Communications with our Board of Directors" below); and

Consulting with our chair and our chief executive officer on matters relating to corporate governance and board performance.

Our nominating and corporate governance committee evaluates our board leadership structure from time to time and may recommend further alterations of this structure in the future.

Director Qualifications

In evaluating director nominees, the nominating and corporate governance committee will consider, among other things, the following factors:

reputation for personal and professional integrity, honesty and adherence to high ethical standards;

demonstrated business acumen, experience and ability to exercise sound judgments in matters that relate to the current and long-term objectives of our company and should be willing and able to contribute positively to the decision-making process of our company;

strong finance experience;

commitment to understand our company and its industry;

interest and ability to understand the sometimes conflicting interests of the various constituencies of our company, which include stockholders, employees, customers, governmental units, creditors and the general public, and to act in the interests of all stockholders;

background and perspective, including specialized expertise and experience in substantive matters pertaining to our business relative to other board members; and

practical and mature business judgment, including the ability to make independent analytical inquiries.

The nominating and corporate governance committee's goal is to assemble a board of directors that brings to the company a variety of perspectives and skills derived from high quality business and professional

Disclaimer

Agios Pharmaceuticals Inc. published this content on April 29, 2026, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on April 29, 2026 at 16:31 UTC.