SEC Form DEF 14A filed by Agios Pharmaceuticals Inc.

88 Sidney Street, Cambridge, Massachusetts 02139

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON THURSDAY, JUNE 18, 2026

Dear Stockholder:

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:

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 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 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].

TABLE OF CONTENTS

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PROXY STATEMENT FOR THE 2026 ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON THURSDAY, JUNE 18, 2026

INFORMATION CONCERNING SOLICITATION AND VOTING

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 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.

GENERAL INFORMATION ABOUT THE ANNUAL MEETING AND VOTING

Why do I have access to these materials?

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.

Why did I receive a notice in the mail regarding the internet availability of proxy materials instead of a full set of proxy materials?

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,

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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.

Can I vote my shares by filling out and returning the Notice?

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.

What does it mean if I receive more than one Notice?

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.

What is the purpose of the Annual Meeting?

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

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

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Why is the 2026 Annual Meeting a virtual, online meeting?

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 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.

How do I virtually attend the Annual Meeting?

We will host the Annual Meeting live online via webcast. In order to attend the Annual Meeting online, 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. 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.

Who can vote?

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.

How many votes do I have?

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.

Is my vote important?

Your vote is important no matter how many shares you own. Please take the time to vote. Take a moment to read the instructions, choose the way to vote that is the easiest and most convenient for you and cast your vote as soon as possible.

How do I vote?

If you are the “record holder” of your shares, meaning that you own your shares in your own name and not through a bank, brokerage firm or other nominee, you may vote:

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If your shares are held in “street name,” meaning they are held for your account by a bank, brokerage firm, or other nominee, you may vote:

Can I change my 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:

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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.

Will my shares be voted if I do not return my proxy?

If your shares are registered directly in your name, your shares will not be voted if you do not vote over the internet, by telephone, or by mail prior to the Annual Meeting or online while virtually attending the Annual Meeting. If you submit a proxy card without giving specific voting instructions on one or more matters listed in the Notice, your shares will be voted as recommended by our board of directors on such matters, and as the proxyholders may determine in their discretion how to vote with respect to any other matters properly presented for a vote at the Annual Meeting.

If your shares are held in “street name,” your brokerage firm may, under certain circumstances, vote your shares if you do not return your voting instructions. Brokerage firms can vote customers’ uninstructed shares on discretionary matters but they will not be allowed to vote your uninstructed shares with respect to non-discretionary items. If you do not timely return voting instructions to your brokerage firm to vote your shares, your brokerage firm may, on discretionary matters, either vote your shares or leave your shares unvoted.

Your brokerage firm cannot vote your uninstructed shares on any matter that is not considered discretionary. Proposal 1, the election of three Class I directors, Proposal 2, an advisory vote on the compensation paid to our named executive officers, or NEOs, and Proposal 3, the approval of an amendment to our 2023 Stock Incentive Plan, as Amended, to increase the number of shares of common stock available thereunder, are not considered discretionary matters. If you do not instruct your brokerage firm on how to vote with respect to these items, your brokerage firm may not vote with respect to these proposals and those votes will be counted as “broker non-votes.” “Broker non-votes” are shares that are held in “street name” by a bank or brokerage firm that indicates on its proxy that it does not have or did not exercise discretionary authority to vote on a particular matter. Proposal 4, the ratification of the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2026, is considered a discretionary matter, and your brokerage firm will be able to vote on that item if it does not receive instructions from you, so long as it holds your shares in its name. We encourage you to provide voting instructions to your brokerage firm or other nominee. This ensures that your shares will be voted at the Annual Meeting according to your instructions. You should receive directions from your brokerage firm or other nominee about how to submit your voting instructions.

How many shares must be represented to hold the Annual Meeting?

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.

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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.

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

Proposal 1 — Election of Directors

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:

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.

Proposal 2 — Advisory Vote on the Compensation Paid to Named Executive Officers

To approve Proposal 2, holders of a majority of the votes cast on the matter must vote FOR the proposal. Proposal 2 is not considered a discretionary matter. Shares which abstain and broker non-votes will not be counted as votes in favor of, or with respect to, this proposal and will also not be counted as votes cast. 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.

Proposal 3 — Amendment of the 2023 Stock Incentive Plan, as Amended

To approve Proposal 3, holders of a majority of the votes cast on the matter must vote FOR the proposal. Proposal 3 is not considered a discretionary matter. Shares which abstain and broker non-votes will not be counted as votes in favor of, or with respect to, this proposal and will also not be counted as votes cast. Accordingly, abstentions and broker non-votes will have no effect on the outcome of this proposal.

Proposal 4 — Ratification of Appointment of Independent Registered Public Accounting Firm

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.

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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.

How does the board of directors recommend that I vote on the proposals?

Our board of directors recommends that you vote:

Are there other matters to be voted on at the Annual Meeting?

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.

Who will count the votes?

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

Will my vote be kept confidential?

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.

How do I submit a question at the Annual Meeting?

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

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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.

How can I find out the results of the voting at 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.

How and when may I submit a stockholder proposal, including a stockholder nomination for director for the 2027 annual meeting of stockholders?

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.

Who is paying the costs of soliciting these proxies?

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.

How do I obtain an Annual Report on Form 10-K?

If you would like a copy of our Annual Report on Form 10-K for the year ended December 31, 2025 that we filed with the SEC, we will send you one, without exhibits, free of charge. Please contact Investor Relations at 88 Sidney Street, Cambridge, Massachusetts 02139; telephone: 617-649-8600; e-mail: [email protected].

All of our SEC filings are also available free of charge in the “Investors—Financials—SEC Filings” section of our website at www.agios.com.

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Whom should I contact if I have any questions?

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].

Cautionary Note Regarding Forward-Looking Statements

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), AQVESME^TM (mitapivat) and tebapivat; the company’s plans, strategies and expectations for its preclinical, clinical and commercial advancement of its drug development, including PYRUKYND^®, AQVESME^TM, 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.

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STOCKHOLDERS SHARING THE SAME ADDRESS

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.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

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

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.

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DELINQUENT SECTION 16(a) REPORTS

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.

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PROPOSAL 1:

ELECTION OF DIRECTORS

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.

Information Regarding Directors

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.

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Nominees for Election to the Board of Directors

Term Expiring at the 2029 Annual Meeting of Stockholders, if elected at the Annual Meeting (Class I)

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

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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.

Members of the Board of Directors Continuing in Office

Term Expiring at the 2027

Annual Meeting of Stockholders (Class II)

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.

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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.

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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.

Term Expiring at the 2028

Annual Meeting of Stockholders (Class III)

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.

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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.

Recommendation of the Board of Directors

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT THE STOCKHOLDERS VOTE FOR THE ELECTION OF EACH OF DR. BALLAL, MR. GOFF AND MS. SMITH.

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CORPORATE GOVERNANCE

General

We believe that good corporate governance is important to ensure that Agios is managed for the long-term 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, 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].

Corporate Governance Guidelines

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:

Corporate Social Responsibility

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

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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, 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 —

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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

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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

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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.

Director Determination of Independence

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.

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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 (ii) 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.

Board Leadership Structure

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:

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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 Nomination Process

Director Qualifications

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

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

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experience. Moreover, the nominating and corporate governance committee believes that the board of directors, considered as a group, should provide a significant mix of experience, knowledge and abilities that will allow the board of directors to fulfill its responsibilities. The nominating and corporate governance committee has not adopted a formal policy with respect to a fixed set of specific minimum qualifications for its candidates for membership on the board of directors. While neither the nominating and corporate governance committee nor the board of directors consider race, ethnicity, gender, or any other basis proscribed by law in selecting nominees, the nominating and corporate governance strives to include individuals with different backgrounds in the pool of candidates from which nominees are recommended.

Our directors’ performance and qualification criteria are reviewed periodically by the nominating and corporate governance committee.

Identification and Evaluation of Nominees for Directors

The nominating and corporate governance committee identifies nominees for director by first evaluating the current members of our board of directors willing to continue in service. Current members with qualifications and skills that are consistent with the nominating and corporate governance committee’s criteria for board of director service and who are willing to continue in service are considered for re-nomination, balancing the value of continuity of service by existing members of our board of directors with that of obtaining a new perspective or expertise.

If any member of our board of directors does not wish to continue in service or if our board of directors decides not to re-nominate a member for re-election, the nominating and corporate governance committee identifies a new nominee that meets the criteria above. The committee generally inquires of our board of directors and members of management for their recommendations. The committee may also review the composition and qualification of the boards of directors of our competitors, and may seek input from industry experts or analysts. The nominating and corporate governance committee reviews the qualifications, experience and background of candidates. Final candidates, if other than our current directors, would be interviewed by the members of the nominating and corporate governance committee and by certain of our other independent directors and executive management. In making its determinations, the nominating and corporate governance committee evaluates each individual in the context of our board of directors as a whole, with the objective of assembling a group that can best contribute to the success of our company and represent stockholder interests through the exercise of sound judgment. After review and deliberation of all feedback and data, the nominating and corporate governance committee makes its recommendation to our board of directors. To date, the nominating and corporate governance committee has engaged third-party search firms to identify board of director candidates. The nominating and corporate governance committee may in the future choose to do so in those situations where particular qualifications are required or where existing contacts are not sufficient to identify an appropriate candidate.

Stockholders may recommend individuals to our nominating and corporate governance committee for consideration as potential director candidates by submitting their names, together with appropriate biographical information and background materials and a statement as to whether the stockholder or group of stockholders making the recommendation has beneficially owned more than 5% of our common stock for at least a year as of the date such recommendation is made, to Nominating and Corporate Governance Committee, c/o Corporate Secretary, Agios Pharmaceuticals, Inc., 88 Sidney Street, Cambridge, Massachusetts 02139. Assuming that appropriate biographical and background material has been provided on or before the date set forth in the section below entitled “Stockholder Proposals,” the committee will evaluate stockholder-recommended candidates by following substantially the same process, and applying substantially the same criteria, as it follows for candidates submitted by others, as described above.

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Communications with Our Board of Directors

Our board of directors will give appropriate attention to written communications that are submitted by stockholders, and will respond if and as appropriate. Our lead director or the chair of our nominating and corporate governance committee, with the assistance of our Corporate Secretary or his or her designee, is primarily responsible for monitoring communications from stockholders and for providing copies or summaries to the other directors as he or she considers appropriate.

Communications are forwarded to all directors if they relate to important substantive matters and include suggestions or comments that the chair of the board considers to be important for the directors to know. In general, communications relating to corporate governance and corporate strategy are more likely to be forwarded than communications relating to ordinary business affairs, personal grievances and matters as to which we receive repetitive or duplicative communications.

Stockholders who wish to send communications on any topic to our board of directors should address such communications to Agios Pharmaceuticals, Inc., c/o Corporate Secretary, 88 Sidney Street, Cambridge, Massachusetts 02139.

Board Meetings and Attendance

Our board of directors met 11 times during fiscal year 2025, including telephonic and virtual meetings. During the year, each of our then-serving directors attended 75% or more of the aggregate number of meetings of the board of directors and the committees on which they served, other than Ms. Owen Adams, who attended 61% of the aggregate number of meetings of the board of directors and the committees on which she served.

Director Attendance at Annual Meetings

Although our company does not have a formal policy regarding attendance by members of our board of directors at our annual meeting, we encourage all of our directors to attend. All of our then-serving directors attended our 2025 annual meeting of stockholders.

Board Committees

We have four standing committees: the audit committee, the compensation & people committee, the nominating and corporate governance committee and the science and technology committee. Each of these committees has a written charter approved by our board of directors. A copy of each charter can be found on the Corporate Governance page of the Investors section of our website, www.agios.com.

Audit Committee

The members of our audit committee are Dr. Ballal, Mr. Capello, and Dr. Ho. Mr. Capello is the chair of the audit committee. Our board of directors has determined that each of Dr. Ballal, Mr. Capello and Ms. Ho qualify as audit committee financial experts within the meaning of SEC regulations and the Nasdaq Listing Rules. In making this determination, our board of directors has considered the formal education and nature and scope of his or her previous experience, coupled with past and present service on various audit committees. Our audit committee assists our board of directors in its oversight of our accounting and financial reporting process and the audits of our financial statements. The audit committee met 13 times during fiscal year 2025, including telephonic and virtual meetings. The audit committee’s responsibilities include:

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Compensation & People Committee

The members of our compensation & people committee are Ms. Foster, Ms. Owen Adams and Ms. Smith. Ms. Smith is the chair of the compensation & people committee. Our compensation & people committee assists our board of directors in the discharge of its responsibilities relating to the compensation of our executive officers and directors. The compensation & people committee met seven times during fiscal year 2025, including telephonic and virtual meetings. The compensation & people committee’s responsibilities include:

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Nominating and Corporate Governance Committee

The members of our nominating and corporate governance committee are Ms. Foster, Dr. Ho and Dr. Scadden. Ms. Foster is the chair of the nominating and corporate governance committee. The nominating and corporate governance committee met four times during fiscal year 2025, including telephonic and virtual meetings. The nominating and corporate governance committee’s responsibilities include:

The processes and procedures followed by our nominating and corporate governance committee in identifying and evaluating director candidates are described above under the heading “Director Nomination Process”.

Science and Technology Committee

The members of our science and technology committee are Drs. Backstrom, Ballal, Scadden and Fouse. Dr. Scadden is the chair of the science and technology committee. The science and technology committee assists our board’s oversight of our research and development activities. The science and technology committee met

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three times during fiscal year 2025, including telephonic and virtual meetings. The science and technology committee’s responsibilities include:

The Board of Directors’ Role in Risk Oversight

Our board of directors has responsibility for the oversight of the company’s risk management processes and, either as a whole or through its committees, regularly discusses with management our major risk exposures, the potential impact of these risks on our business and the steps we take to manage them. The risk oversight process includes overseeing our periodic, company-wide enterprise risk management evaluation and receiving regular reports from board committees and members of senior management to enable our board of directors to understand the company’s risk identification, risk management and risk mitigation strategies with respect to areas of potential material risk, including operations, finance, legal, regulatory, strategic, reputational and human capital risk. Our chair promotes effective and transparent communication and consideration of matters presenting significant risks to the company through her role in developing the board’s meeting agendas, presiding over meetings and facilitating communications between management and the board of directors. Our lead director also promotes consideration of matters presenting significant risks to the company through her role of working with our chair and chief executive officer in preparing the board’s meeting agenda and determining the need for special meetings and facilitating communications between members of our board of directors, our chair and our chief executive officer.

The audit committee reviews information regarding liquidity and operations, and oversees our management of financial risks and provides direct oversight over our cybersecurity risk. Periodically, the audit committee reviews our policies with respect to risk assessment, risk management, loss prevention and regulatory compliance. Oversight by the audit committee includes direct communication with our external auditors, discussions with our chief compliance officer to monitor and review our regulatory compliance efforts, and discussions with management regarding significant financial and other risk exposures and risks relating to data privacy and cybersecurity and the actions management has taken to limit, monitor or control such exposures. The compensation & people committee is responsible for ensuring that our compensation programs properly align

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pay with performance, assessing whether any of our compensation policies or programs has the potential to encourage excessive risk-taking and for assessing risk with respect to human capital management. Oversight by the compensation & people committee includes direct communication with our compensation consultants. The nominating and corporate governance committee manages risks associated with the board and committee composition, independence of the board of directors, corporate disclosure practices, potential conflicts of interest, ESG issues and management succession planning. The science and technology committee assists the board of directors’ oversight of the company’s long-term strategic goals, research and development activities and enterprise risk management in the areas affecting research and development. While each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire board of directors is regularly informed through committee reports about such risks. Matters of significant strategic risk are considered by our board of directors as a whole.

We undertake a comprehensive enterprise risk management analysis on a periodic basis in an effort to identify and prioritize key risks facing our company in the short-, medium-and long-term time frames, and our management team communicates the findings of this analysis to the audit committee and our entire board of directors on a periodic basis. Our board of directors believes that full and open communication between management, the committees and the board of directors is essential for effective risk management and oversight, including with respect to financial, regulatory, cybersecurity, human capital management, board and ESG topics and risks.

Risk Considerations in our Compensation Program

We along with our compensation & people committee of our board of directors have reviewed the compensation policies and practices for all of our employees and believe any risks arising from our compensation policies and programs are not reasonably likely to have a material adverse effect on our company or its operations. In reaching this conclusion, we and the compensation & people committee considered several factors, including the following:

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Director Compensation

Our board of directors has adopted a non-employee director compensation policy that is designed to provide a total compensation package that enables us to attract and retain, on a long-term basis, high caliber non-employee directors. The cash and equity compensation for non-employee directors under the policy, effective January 1, 2025, is set forth in the table below.

* number of shares for stock option and RSU awards to be determined on the date of grant based on grant date fair value.

Under the policy, non-employee members of our board of directors also are reimbursed for travel, lodging and other reasonable expenses incurred in attending board of directors or committee meetings.

The stock options granted to our non-employee directors have an exercise price equal to the fair market value of our common stock on the date of grant and expire ten years after the date of grant. The stock options and RSUs granted to our non-employee directors are subject to vesting based upon a director’s continued service on our board of directors. The initial stock options granted to our newly elected non-employee directors vest with

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respect to 25% of the shares on the first anniversary of the grant date and monthly thereafter until the fourth anniversary of the date of grant. The initial RSUs granted to our newly elected non-employee directors vest as to one-third of the underlying shares each year following the grant date. The annual stock options and RSUs granted to our non-employee directors vest with respect to 100% of the shares on the first anniversary of the grant date. To the extent that a non-employee director has other responsibilities, such director may receive additional compensation to the extent deemed appropriate by our board of directors. Directors who also are employees do not receive cash or equity compensation for service on the board of directors in addition to compensation payable for their service as employees.

The following table sets forth information concerning the compensation for our non-employee directors during the fiscal year ended December 31, 2025:

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Mr. Goff, who serves as our chief executive officer and a member of our board of directors, did not receive any additional compensation for his service as a director during 2025. The compensation that we paid to Mr. Goff in his role as our chief executive officer is disclosed under “Executive Compensation–Summary Compensation Table.”

Limitation of Liability and Indemnification

Our certificate of incorporation limits the personal liability of directors for breach of fiduciary duty to the maximum extent permitted by the Delaware General Corporation Law and provides that no director will have personal liability to us or to our stockholders for monetary damages for breach of fiduciary duty or other duty as a director. However, these provisions do not eliminate or limit the liability of any of our directors:

Any amendment to or repeal of these provisions will not eliminate or reduce the effect of these provisions in respect of any act, omission or claim that occurred or arose prior to such amendment or repeal. If the Delaware General Corporation Law is amended to provide for further limitations on the personal liability of directors of corporations, then the personal liability of our directors will be further limited to the greatest extent permitted by the Delaware General Corporation Law.

In addition, our certificate of incorporation provides that we must indemnify our directors and officers and we must advance expenses, including attorneys’ fees, to our directors and officers in connection with legal proceedings, subject to very limited exceptions.

We maintain a general liability insurance policy that covers certain liabilities of our directors and officers arising out of claims based on acts or omissions in their capacities as directors or officers. In addition, we have entered into indemnification agreements with our directors and executive officers. These indemnification agreements require us, among other things, to indemnify each such director and executive officer for some

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expenses, including attorneys’ fees, judgments, fines and settlement amounts incurred by him in any action or proceeding arising out of his service as one of our directors or executive officers.

Certain of our non-employee directors may, through their relationships with their employers, be insured and/or indemnified against certain liabilities incurred in their capacity as members of our board of directors.

Insofar as indemnification for liabilities arising under the Securities Act of 1933, as amended, or the Securities Act, may be permitted to directors, executive officers or persons controlling us, in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

Executive and Director Compensation Processes

The compensation & people committee generally meets at least four times annually and with greater frequency if necessary. The agenda for each meeting is usually developed by the chair of the compensation & people committee, in consultation with the chief executive officer or the chief people officer. The compensation & people committee meets regularly in executive session. From time to time, various members of management and other employees as well as outside advisors or consultants are invited by the compensation & people committee to make presentations, provide financial or other background information or advice or otherwise participate in compensation & people committee meetings. The chief executive officer may not participate in, or be present during, any deliberations or determinations of the compensation & people committee regarding his or her compensation. The charter of the compensation & people committee grants the compensation & people committee full access to all of our books, records, facilities and personnel, as well as authority to obtain, at our expense, advice and assistance from internal and external legal, accounting or other advisors and consultants and other external resources that the compensation & people committee considers necessary or appropriate in the performance of its duties. In particular, the compensation & people committee has the sole authority to retain compensation consultants to assist in its evaluation of executive and director compensation, including the authority to approve the consultant’s reasonable fees and other retention terms.

During the fiscal year ended December 31, 2025, the compensation & people committee directly engaged the Human Capital Solutions practice at Aon plc, or Aon, to advise the compensation & people committee on our compensation program for executive officers, which includes base salaries, annual performance-based cash incentives and equity incentive awards, and on our non-employee director compensation policy. Aon did not determine or make recommendations to the compensation & people committee regarding the specific amount or form of compensation of our executive officers or directors for fiscal year ended December 31, 2025, other than recommendations with respect to the proposed amendment to our 2023 Stock Incentive Plan, as Amended.

Historically, the compensation & people committee has made (or has recommended that the independent members of the board of directors make) most of the significant adjustments to annual compensation, determined bonus and equity awards and established new performance objectives at one or more meetings held during the last quarter of the year and the first quarter of the following year. However, the compensation & people committee also considers matters related to individual compensation, such as compensation for new executive hires, as well as high-level strategic issues, such as the efficacy of our compensation strategy, potential modifications to that strategy and new trends, plans or approaches to compensation, at various meetings throughout the year. The compensation & people committee is responsible for making determinations regarding compensation of our executive officers other than our chief executive officer, making changes to pre-approved salary ranges, salary increases, equity awards, incentive payments and pre-approved equity ranges for new hires and high performers, the initiation of offerings under our 2013 employee stock purchase plan and making material changes to benefits offered to our employees. In addition, the compensation & people committee makes recommendations to our board of directors regarding the compensation of directors and the chief executive officer. Under its charter, the compensation & people committee may form, and delegate authority to,

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subcommittees, consisting of independent directors, as it deems appropriate. During fiscal year 2025, the compensation & people committee did not form or delegate authority to such subcommittees. During fiscal year 2025, the compensation & people committee delegated to the chief executive officer, or if the chief executive officer was unavailable, the chief financial officer, decision-making authority related to initial salary levels and salary adjustments, incentive payments and option and RSU grants for all non-executive officers, and non-material changes to employee benefits. Such delegated decision-making is governed by guidelines established by the compensation & people committee.

Report of the Audit Committee of the Board of Directors

The audit committee oversees the company’s financial reporting process on behalf of the board of directors. We have reviewed the company’s audited consolidated financial statements for the fiscal year ended December 31, 2025 and discussed them with company management and PricewaterhouseCoopers LLP, the company’s independent registered public accounting firm.

We have received from, and discussed with, PricewaterhouseCoopers LLP, which is responsible for expressing an opinion on the conformity of the company’s audited consolidated financial statements with accounting principles generally accepted in the United States, its judgments as to the quality, not just the acceptability, of the company’s accounting principles and such other matters as are required to be discussed by the applicable requirements of the SEC and the Public Company Accounting Oversight Board, or the PCAOB. In addition, we have received from PricewaterhouseCoopers LLP the written disclosures and the letter required by applicable requirements of the PCAOB regarding its communications with us concerning independence, have considered the compatibility of non-audit services with the auditors’ independence and have discussed with PricewaterhouseCoopers LLP its independence from management and the company.

Based on the review and discussions referred to above, we recommended to the board of directors that the audited consolidated financial statements be included in the company’s Annual Report on Form 10-K for the year ended December 31, 2025.

This report of the audit committee is not “soliciting material,” shall not be deemed “filed” with the SEC and shall not be incorporated by reference by any general statement incorporating by reference this Proxy Statement into any filing under the Securities Act, or the Exchange Act, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing, except to the extent that we specifically incorporate this information by reference, and shall not otherwise be deemed filed under such acts.

The foregoing report has been furnished by the audit committee.

Respectfully submitted,

The Audit Committee of the Board of Directors

Jeffrey Capello (chair)

Rahul Ballal, Ph.D.

Maykin Ho, Ph.D.

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EXECUTIVE OFFICERS

The following table sets forth information regarding our executive officers as of April 1, 2026:

The biography of Mr. Goff can be found under “Nominees for Election to the Board of Directors.”

James Burns has served as our chief legal officer since January 2022. Mr. Burns joined Agios in 2016 as a senior attorney and the first head of compliance, after which he served as Senior Vice President and General Counsel. Mr. Burns has more than 19 years of legal and compliance experience in the pharmaceutical industry. Prior to joining Agios, Mr. Burns held roles of increasing responsibility at EMD Serono Inc., a biotechnology company, culminating in his position as associate general counsel for commercial. Mr. Burns began his legal career as a corporate attorney at Testa, Hurwitz and Thibeault LLP and Goodwin Procter LLP. Mr. Burns holds a B.A. degree from Seton Hall University and a J.D. from Seton Hall University School of Law.

Cecilia Jones has served as our chief financial officer since September 2022. Prior to joining Agios, Ms. Jones served as Chief Financial Officer of LogicBio Therapeutics, Inc., or LogicBio, a gene therapy company, from January 2021 to September 2022. Prior to joining LogicBio, Ms. Jones worked at Biogen, where she held a variety of roles beginning in November 2010, most recently serving as Vice President, Finance from June 2019 until January 2021 and as Senior Director, Corporate Finance from July 2015 to June 2019. Before Biogen, Ms. Jones served in various roles in financial planning and analysis at Interactive Data Corporation, a financial market data company, and Genzyme Corporation (prior to its acquisition by Sanofi S.A.). Ms. Jones has an M.B.A. from the Harvard Business School and an economics degree from Universidad de San Andres in Buenos Aires, Argentina.

Sarah Gheuens, M.D., Ph.D. has served as our chief medical officer since September 2021 and as head of research & development since July 2022. She joined the company in December 2019, and prior to her appointment as chief medical officer, she served as head of clinical development for our genetically defined disease programs and as interim head of regulatory affairs. Prior to joining Agios, Dr. Gheuens worked at Biogen from 2012 to 2019, where she held roles of increasing responsibility in safety, medical affairs and clinical development. Before joining Biogen, Dr. Gheuens worked at Beth Israel Deaconess Medical Center, or BIDMC, a hospital, from 2008 to 2012, taking care of patients with HIV and neurological complications and doing research on progressive multifocal leukoencephalopathy. Dr. Gheuens serves on the board of directors and on the science and technology committee of Viridian Therapeutics, Inc., a publicly traded biotechnology company. Dr. Gheuens received her medical degree from the Free University of Brussels (VUB), Belgium, and completed her neurology residency at the University Hospital of the Free University of Brussels, Belgium, followed by an HIV/neurology fellowship at BIDMC. She also holds a Ph.D. in Medical Sciences from the University of Antwerp, Belgium, and a Master’s in Medical Sciences from Harvard Medical School.

Tsveta Milanova has served as our chief commercial officer since January 2023. Prior to joining Agios, Ms. Milanova served as SVP, Head of US Commercial of Alexion from December 2020 to September 2022, as SVP, Head of Global Commercial Strategy of Alexion from January 2019 to December 2020 and SVP, Head of Global Value, Access & Policy of Alexion from April 2018 to December 2018. Prior to joining Alexion,

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Ms. Milanova worked at Celgene from October 2008 to April 2018, where she held a variety of roles, most recently as Global Head, Pricing and Market Access Haematology/Oncology. Before Celgene, Ms. Milanova served as Global Health Outcomes Manager at GlaxoSmithKline R&D, a healthcare company, from October 2004 to October 2008. Ms. Milanova holds a master of science (MSc) degree in international health policy and health economics from the London School of Economics, a master of science (MSc) degree in pharmacy from the Medical University of Sofia, Bulgaria and is a graduate of Harvard’s Advanced Management Program.

Krishnan Viswanadhan, Pharm.D. has served as our chief corporate development & strategy officer since March 2025. Prior to joining Agios, Dr. Viswanadhan served as president and chief operating officer at Be Biopharma, a private biotechnology company, from 2021 to 2025. Prior to joining Be Biopharma, from 2019 to 2021 Dr. Viswanadhan was Senior Vice President, Global Cell Therapy at BMS, in which role he oversaw the teams responsible for the development, approval, and life cycle management of Breyanzi, a CD19 CAR T and Abecma, the first BCMA CAR T therapy. Before that, Dr. Viswanadhan was Vice President, Business Development and Global Alliances at Celgene, responsible for managing the portfolio of partnerships and equity investments. Prior to Celgene, he had roles in large and small companies in regulatory strategy. Dr. Viswanadhan serves on the board of directors of Multiply Labs, a private health technology company. Dr. Viswanadhan is a registered pharmacist and earned a Pharm.D from Rutgers University and an MBA from Cornell University.

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EXECUTIVE COMPENSATION

Compensation Discussion and Analysis

Our compensation & people committee is responsible for reviewing and approving, or recommending for approval by the board of directors, the compensation of our named executive officers, or NEOs, including salary, cash and equity incentive compensation levels, severance arrangements, change in control benefits and other forms of executive compensation. This committee is also responsible for evaluating our company’s performance against its goals and making related recommendations to our board of directors, assessing the performance of our NEOs, and ensuring our compensation program is aligned with the objectives described below and competitive with those of other companies in our industry that compete with us for talent. This section discusses the principles underlying our compensation & people committee’s policies and decisions with respect to the compensation of our NEOs.

Our NEOs for 2025 were as follows:

Say-on-Pay Vote Support and Stockholder Engagement

At our 2025 annual meeting of stockholders, we conducted a non-binding advisory vote on the compensation of our NEOs, commonly referred to as a “say-on-pay” vote, in accordance with the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010. Approximately 94% of the votes cast by stockholders on this proposal, excluding broker non-votes, were cast in support of the compensation paid to our named executive officers in 2024. While this vote is a non-binding advisory vote, our compensation & people committee and board of directors take the voting results into account in determining the compensation of our NEOs. In light of the strong level of support evidenced by last year’s say-on-pay vote, among other factors, our compensation & people committee decided to maintain our general approach to executive compensation and made no significant changes to our executive compensation program in 2025.

Our compensation & people committee and board of directors will continue to consider stockholder input and monitor our executive compensation program to ensure it aligns the interests of our executive officers with the interests of our stockholders and adequately addresses input from our stockholders.

2025 Highlights

Agios advanced strategic priorities across our portfolio in 2025. We achieved several key milestones for our mitapivat franchise. The year came to a close with the approval of mitapivat under the brand name AQVESME^™ by the U.S. Food and Drug Administration, or FDA, in December 2025, the only FDA-approved medicine to treat anemia in adults with non-transfusion dependent and transfusion-dependent alpha- or beta-thalassemia. We commercially launched AQVESME^™ in the U.S. in late January 2026. In connection with this submission, we also implemented a Risk Evaluation and Mitigation Strategy program to mitigate the risk of

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hepatocellular injury in response to FDA feedback received late in the review cycle. Outside of the United States, the Committee for Medicinal Products for Human Use, or CHMP, of the European Medicines Agency adopted a positive opinion for the new indication for mitapivat under the brand name PYRUKYND^® in adults for the treatment of anemia associated with transfusion-dependent and non-transfusion-dependent alpha- or beta-thalassemia. The European Commission is reviewing the CHMP’s opinion, with the final decision expected in early 2026. Finally, in August 2025, the Saudi Food and Drug Authority approved mitapivat under the brand name PYRUKYND^® for the treatment of adults with non-transfusion dependent and transfusion-dependent alpha- or beta-thalassemia, the first ever Saudi approval of a drug ahead of any other major regulatory body elsewhere.

We also continued to advance mitapivat in SCD and PK deficiency. In November 2025, we reported topline data from the phase 3 portion of RISE UP, a phase 2/3 study evaluating the efficacy and safety of PYRUKYND^® in SCD patients 16 years of age or older, which met its primary endpoint of hemoglobin response and key secondary endpoints of change from baseline in hemoglobin concentration and change from baseline in indirect bilirubin. While the phase 3 portion of the trial also showed a reduction in its second primary endpoint of annualized rate of sickle cell pain crises compared to placebo, this trend did not achieve statistical significance. In March 2026, we announced that we plan to submit a supplemental New Drug Application, or sNDA, for mitapivat in SCD for accelerated approval, based on FDA feedback received following a pre-sNDA meeting, and we have submitted a proposal for the confirmatory clinical trial required in connection with the filing. With respect to PK deficiency, in February 2025, we reported positive topline data from ACTIVATE-kids, our double-blind phase 3 study evaluating the efficacy and safety of mitapivat as a potential treatment for PK deficiency in patients between one and 18 years old who are not regularly transfused. During 2025, we also continued to make progress in commercializing PYRUKYND^® in PK deficiency in the United States and across the world, recording $54.0 million in total worldwide revenue for the year ended December 31, 2025, reflecting strong growth year-over-year, compared to $36.5 million for the year ended December 31, 2024. To support these efforts, in June 2025, we entered into a distribution agreement with Avanzanite Bioscience B.V., or Avanzanite, pursuant to which we granted Avanzanite the right to commercialize PYRUKYND^® in the European Economic Area, Switzerland and the United Kingdom.

In addition to the above achievements, we continued to advance our pipeline across our portfolio. With respect to tebapivat, our novel PK activator, we completed patient enrollment in both our phase 2b study in patients with LR MDS and our phase 2 study in patients with SCD. In addition, we completed our phase 1 healthy volunteer study of AG-181, our phenylalanine hydroxylase stabilizer, for the treatment of phenylketonuria, and initiated a phase 1 healthy volunteer study of AG-236, an siRNA targeting the transmembrane serine protease 6 gene, or TMPRSS6, intended for the treatment of polycythemia vera, or PV.

To support this continued execution against our strategic priorities, we appointed Krishnan Viswanadhan, Pharm.D as our chief corporate development & strategy officer effective March 5, 2025. During 2025 we also continued to refresh our board of directors, adding a new non-employee director, Dr. Jay Backstrom, following the departure of long-tenured director Dr. David Schenkein.

In addition to the above achievements, we attracted, retained and fostered the development of our high caliber team and strengthened our company culture of inclusion. We exercised financial discipline by managing our cash spending in line with our board-approved budget, thereby maintaining our balance sheet strength to continue to maintain the financial positioning of the company in challenging macroeconomic conditions.

Based upon an evaluation of our performance against each of our goals for 2025 and the weighting assigned to each, the board of directors determined, upon recommendation from the compensation & people committee, that, with respect to our annual performance-based cash incentive program, we achieved an overall result of 100% for the year. For more information with respect to our performance-based cash incentive program, see “Executive Compensation Elements–Annual Performance-based Cash Incentives” below.

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Executive Compensation Overview

To foster the future success of the company, we reward our executives in a manner that reinforces our pay-for-performance philosophy and culture. Our compensation & people committee is committed to ensuring that a substantial portion of executive compensation is “at-risk” and variable. As such, 89% of Mr. Goff’s total direct compensation for 2025 and, on average, 78% of total target direct compensation for 2025 for our other NEOs (excluding Dr. Viswanadhan, who joined the company during 2025 and whose new hire equity grants in 2025 were not representative of our annual compensation philosophy for executive officers and also excluding the supplemental grants made to Ms. Jones and Mr. Burns in February 2025, which are described below under “Supplemental 2025 Equity Grants”) is at-risk and directly affected by both the company’s and each NEO’s performance. While we do not have a formal or informal policy for allocating between long-term and short-term compensation, between cash and non-cash compensation or among different forms of non-cash compensation, we generally strive to provide our NEOs with a balance of short-term and long-term incentives and a mix of cash and non-cash compensation to encourage consistently strong performance.

In February 2025, the compensation & people committee approved 2025 base salaries, 2024 performance-based cash incentive awards and annual stock option, restricted stock unit, or RSU, and PSU awards for our NEOs, other than Mr. Goff and Dr. Viswanadhan (who began employment in March 2025, received new-hire equity grants in March 2025 and was only granted an annual PSU award as part of the 2025 executive compensation cycle). Upon the recommendation of our compensation & people committee, in February 2025, our board of directors approved the 2025 base salary, 2024 performance-based cash incentive award and annual stock option, RSU and PSU awards for Mr. Goff. In December 2024, our compensation & people committee approved the 2025 base salary, target 2025 performance-based cash incentive award, new hire equity awards (consisting of options, RSUs and PSUs) and sign-on bonus for Dr. Viswanadhan, who was appointed our chief corporate development & strategy officer effective March 5, 2025.

In February 2026, the compensation & people committee approved 2026 base salaries, 2025 performance-based cash incentive awards and annual stock option, RSU and PSU awards for our NEOs, other than for Mr. Goff. Upon the recommendation of our compensation & people committee, in February 2026, our board of directors approved the 2026 base salary, 2025 performance-based cash incentive award and annual stock option, RSU and PSU awards for Mr. Goff. See the section entitled “—2026 Executive Compensation Decisions” for more information regarding the 2026 compensation of our NEOs.

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We have developed and periodically reassess our executive compensation program to align with current governance and best practices while ensuring our ability to achieve our stated objectives and philosophy and support our ambitious business goals:

Compensation Objectives and Philosophy

Our mission is to develop and deliver transformative therapies for patients living with rare diseases. Our compensation & people committee believes that the most effective compensation program is one that rewards sustainable value creation for stockholders, through the delivery of strong company performance, as well as tangible progress toward achieving our mission to improve the lives of patients. The objectives of our compensation program are to:

To achieve its objectives, our compensation & people committee evaluates our executive compensation program with the goal of setting total compensation at levels that align with our culture, total rewards strategy, size, life stage and industry peers. Specifically, our compensation & people committee uses competitive market

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compensation data from an annual total compensation study of peer companies to inform its decisions about base salary and variable compensation as part of its review of overall compensation opportunities and the specific elements of our compensation program. The compensation & people committee uses multiple reference points when establishing target compensation levels and considers not only competitive market data to establish targeted pay levels but also factors such as company and individual performance, scope of responsibility, critical needs and skill sets, leadership potential and succession planning. The compensation & people committee also evaluates the compensation programs of other companies which, while not in our peer group, have similar characteristics with regard to business model, complexity and sophistication.

In addition, our executives also receive a significant portion of their executive compensation in the form of long-term equity incentive compensation through the grants of stock options and RSUs that vest over time, and PSUs that vest upon the achievement of specified corporate milestones. We believe our long-term incentive awards facilitate retention and align the interests of our NEOs with those of our stockholders by allowing them to participate in the longer-term success of our company and the intended appreciation of our stock price. Aligned with the objectives described above, our compensation & people committee also considers a number of factors when comparing to our peers in determining equity incentive compensation for our NEOs, including annual long-term incentive values, annual equity awards expressed as a percentage of total shares outstanding, total annual and cumulative dilution, the retentive value of outstanding awards and total equity ownership. Given the dynamic biopharmaceutical market, the compensation & people committee does not overemphasize any one factor. Rather, the compensation & people committee takes a holistic view, further considering the achievement of company goals and how that impacts total stockholder return, as well as market data of our peer group, when determining actual award levels for the NEOs. We believe that designing our overall compensation program in this manner is necessary and appropriate to attract and retain the quality of talent we need to successfully grow our business, achieve our challenging goals, sustain strong performance, and differentiate ourselves from those companies against which we compete for talent while ensuring pay-for-performance alignment.

Overview of Executive Compensation Process

As a part of evaluating and determining NEO performance and compensation, our compensation & people committee receives recommendations from our chief executive officer (except with respect to his own performance and compensation). Our chief executive officer’s performance and compensation is approved by our board of directors based upon the recommendation of our compensation & people committee. The evaluation of each of our NEOs is based on our overall corporate performance against annual goals that are approved by the board of directors at the beginning of each year, as discussed in more detail below.

The compensation & people committee has the sole authority to retain, at our expense, one or more third-party compensation consultants to assist the compensation & people committee in performing its responsibilities. The compensation & people committee may terminate the services of the consultant if the compensation & people committee deems it appropriate. In 2025, the compensation & people committee utilized the services of Aon to assist it in fulfilling its responsibilities. Aon was retained exclusively by the compensation & people committee and has not been retained by management to perform any work for the company other than projects performed at the direction of the compensation & people committee. Aon provides analysis and recommendations regarding:

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In addition, we subscribe to Aon’s various global annual and specialized life sciences and general industry surveys on an ongoing basis. Aon advised the compensation & people committee on all of the principal aspects of executive compensation for 2025. Aon consultants attend meetings of the compensation & people committee, including executive sessions in which executive compensation issues are discussed, when requested to do so. Aon reports to the compensation & people committee and not to management, although it meets with management for purposes of gathering information for its analyses and recommendations. The compensation & people committee annually evaluates its engagement of compensation consultants, and selected Aon to advise with respect to compensation matters based on Aon’s industry experience and reputation, which our compensation & people committee concluded gave Aon useful context and knowledge to advise it. The compensation & people committee has assessed the independence of Aon pursuant to SEC and Nasdaq rules and concluded that no conflict of interest exists between Aon and the company, and that Aon is independent.

Annual base salaries for the current year, and annual performance-based cash incentives and equity incentive awards for the prior year are generally determined in the first quarter of the year based on company and individual performance of the prior year, as well as other factors, including compensation trends in the biopharmaceutical industry and among our benchmark peers. Our compensation & people committee may also review or determine the compensation of our executive officers throughout the course of the year, including in connection with new hires, promotions or other special circumstances as our compensation & people committee determines appropriate.

Use of Comparator Peer Group

The compensation & people committee benchmarks our executive compensation against a peer group of companies to determine competitiveness and market trends. The compensation & people committee reviews the companies in our peer group annually, reviews Aon’s recommendations regarding which companies should be included in the peer group and makes adjustments as necessary to ensure the peer group continues to properly reflect comparable companies based on industry, market capitalization and headcount, as well as companies with which we compete for talented executives. The compensation & people committee also annually reviews the executive pay practices of other similarly situated companies as reported by Aon through industry surveys and proxy analyses specific to the biopharmaceutical and biotechnology sectors. The compensation & people committee considers this information when making determinations for each element of compensation.

In developing the peer group of companies to inform 2025 compensation decisions, our compensation & people committee, with the assistance of Aon, established a peer group of 14 publicly traded, national and regional companies in the biopharmaceutical industry based on a balance of the following criteria:

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Based on these criteria, our peer group for 2025 was comprised of the following 14 companies:

The compensation & people committee believes the compensation practices of our peer group provide us with appropriate compensation benchmarks for evaluating the compensation of our NEOs. Notwithstanding the similarities of the peer group to our company, due to the nature of our business, we compete for executive talent with many companies that are larger and more established than we are or that possess greater resources than we do, as well as with prestigious academic and non-profit institutions. Other considerations, including market factors, the experience level of the executive and the executive’s performance against established corporate goals and individual objectives, may require that our compensation & people committee vary from its historic compensation practices or deviate from its general compensation philosophy under certain circumstances.

For the purposes of informing 2026 compensation decisions, the compensation & people committee, with the advice of Aon, examined the peer group list and, with reference to market capitalization, therapeutic area, stage of development, number of employees and other key business metrics, approved the following 2026 peer group:

Our compensation & people committee made adjustments to our 2026 peer group to ensure it represented a group of biopharmaceutical companies that aligns with us in key measures based on our disease area focus, the current state of our commercialization efforts, and our development pipeline, focusing on companies with:

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Specifically, ACADIA Pharmaceuticals Inc. was removed from the 2026 peer group because the company’s revenue moved outside of our targeted range, and Sage Therapeutics, Inc. was removed from the 2026 peer group due to the company having been acquired. Axome Therapeutics, Inc., Iovance Biotherapeutics, Inc., Soleno Therapeutics, Inc., Syndax Pharmaceuticals, Inc., and TG Therapeutics, Inc. were added to the 2026 peer group through an evaluation of potential peers meeting the above criteria.

Executive Compensation Elements

The primary elements of our executive compensation program are:

Our compensation & people committee uses its judgment to allocate long-term and short-term compensation for our NEOs, in alignment with our pay-for-performance philosophy and the long-term interests of stockholders. After reviewing information provided by our compensation consultant and other relevant data, our compensation & people committee determines what it believes to be the appropriate level and mix of the various compensation components. The compensation & people committee generally strives to provide our NEOs with a balance of short-term and long-term incentives to encourage consistently strong performance. Ultimately, the compensation & people committee’s objective in allocating between long-term and short-term compensation is to ensure adequate base compensation to attract and retain talent, while providing incentives to maximize long-term value for our company and our stockholders. Therefore, we provide cash compensation in the form of base salary to meet competitive salary norms and reward performance on an annual basis. We also provide cash compensation in the form of performance-based cash incentive compensation designed to incentivize and reward performance based on specific short-term annual company goals. To further focus our NEOs on longer-term performance, we rely upon equity-based incentive awards that vest over a meaningful period of time or upon the achievement of meaningful corporate milestones, thereby reinforcing stockholder value creation. In addition, we provide our executives with benefits that are available to all employees, including medical, vision and dental insurance; life and disability insurance; medical and dependent care flexible spending accounts; a 401(k) plan; and an opportunity to invest in our company pursuant to our employee stock purchase plan. Finally, we offer our NEOs severance benefits to align with market practice and to incentivize them to continue to strive to achieve stockholder value in connection with change in control situations.

Base Salaries

Base salaries are used to recognize the experience, skills, knowledge and responsibilities required of our NEOs. Base salaries for our NEOs typically are established through arm’s length negotiation at the time the NEO

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is hired or promoted, taking into account the position for which the NEO is being considered and the NEO’s qualifications, prior experience and salary expectations. None of our NEOs is currently party to an employment agreement that provides for automatic or scheduled increases in base salary and we do not provide formulaic base salary increases to our NEOs. However, on an annual basis, our compensation & people committee reviews and evaluates, with input from our chief executive officer for all other NEOs, the need for adjustment of the base salaries of our NEOs based on changes and expected changes in the scope of a NEO’s responsibilities, including promotions, the individual contributions made by and performance of the NEO during the prior year, the NEO’s performance over a period of years, overall labor market conditions, the relative ease or difficulty of replacing the executive with a well-qualified person, our overall growth and development as a company and general salary trends in our industry and among our peer group and where the NEO’s salary falls in the salary range presented by that data. In making decisions regarding salary increases, the compensation & people committee may also draw upon the experience of members of our board of directors with other companies.

In February 2025, based on a review of market data provided by Aon and the factors described above, including the current compensation levels of our NEOs and company performance and individual contributions, our compensation & people committee or board of directors, as applicable, approved 2025 salary increases for our NEOs, other than Dr. Viswanadhan. Dr. Viswanadhan was appointed our chief corporate development & strategy officer effective March 5, 2025, and his 2025 base salary was approved by the compensation & people committee in December 2024.

The 2024 and 2025 annual base salaries of each of our NEOs were:

Annual Performance-based Cash Incentives

We have designed our annual performance-based cash incentive program, which is guided by specified annual corporate and individual goals and contributions, to emphasize pay-for-performance and to reward our NEOs for our performance during the preceding year. The target pay opportunity of the annual cash incentive for the chief executive officer is determined by our board of directors, based upon the recommendation of our compensation & people committee, and the amount of the target pay opportunity of the annual cash incentive for all other NEOs is determined by our compensation & people committee with input from our chief executive officer. In making such determinations and recommendations, the compensation & people committee examined the totality of anticipated and unanticipated achievements by us and each NEO in the preceding year, including our performance against specific research, clinical, regulatory, operational and financial company goals. In recent years, these annual company goals have primarily focused on the advancement of our most advanced programs.

Our compensation & people committee determined to formally cap annual performance-based cash incentive program funding in any given year at 150% of the target payout level. Under our annual performance-based cash incentive program, individual cash incentive awards are determined by first establishing a cash incentive pool, which is adjusted based upon recommendations by our compensation & people committee and

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upon approval by our board of directors based on the company’s performance as measured against the company’s predetermined annual goals and then allocated among all eligible program participants. Our board of directors, upon recommendation of our compensation & people committee, annually evaluates the company’s strategic priorities for the upcoming year and assigns appropriate relative weightings for the annual corporate goals. Below is the list of the company’s 2025 goals and relative weighting assigned to each goal, as considered by our compensation & people committee and board of directors in their respective assessment of company performance in 2025.

Certain of these corporate goals include highly sensitive and competitive data, including preclinical, clinical, regulatory, strategic and financial targets. We do not disclose the specific portions of these goals because

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we believe that such disclosure would result in competitive harm to us. We purposely set these goals at challenging levels. Revealing certain elements of these goals could potentially reveal insights about our preclinical, clinical, regulatory, financial and strategic plans or objectives that our competitors or potential collaborators could use against us.

In January 2026, our chief executive officer recommended to our compensation & people committee that our company’s performance against 2025 goals be assessed based on the company’s achievements against these goals during the year, which achievements are discussed above under “Compensation Discussion and Analysis—Executive Summary”. Based on the balance of the company’s relative achievement against our 2025 goals, the overall company performance score for 2025 was determined to be 100% by our board of directors upon the recommendation of the compensation & people committee. Below is our relative weighted performance against our 2025 goals, as determined by our board of directors.

Our compensation & people committee also evaluates the individual performance of our NEOs, with the input of our chief executive officer in the case of the evaluation of our other NEOs, and makes recommendations to our board of directors with regard to the evaluation of our chief executive officer’s individual performance. Consistent with this process, our compensation & people committee assessed the performance of Mr. Goff in 2025 based on our relative achievement of our corporate goals as well as his individual performance and leadership in driving the execution of our strategic plans.

In assessing the individual performance of our NEOs other than our chief executive officer, our compensation & people committee, with the input of our chief executive officer, considered each such officer’s individual contributions to the completion of our 2025 goals, and the officer’s individual achievements in helping to build the company and execute on our strategy. These achievements include the following:

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Based on company and individual performance, our board of directors approved, upon the recommendation of the compensation & people committee, the 2025 cash incentive payment for Mr. Goff, and the compensation & people committee approved the 2025 cash incentive payments for our other NEOs, as follows:

The 2025 cash incentive payments for all employees, including the NEOs, were earned in 2025 and paid in 2026.

As discussed below under “—2026 Executive Compensation Decisions”, the annual cash incentive target award percentages for 2026 performance for our NEOs remain unchanged from 2025 and 2024.

Equity Incentive Awards

Our equity award program is the primary long-term incentive compensation vehicle for our executives. We believe that equity grants provide our executives with a strong link to our long-term performance, create an ownership culture and help to align the interests of our executives and our stockholders. Our executives benefit from stock option and RSU awards as our stock price increases through the creation of stockholder value; similarly, the PSU awards granted to our executives vest only after the achievement of specified company performance milestones. Accordingly, we believe stock option, RSU and PSU awards provide meaningful incentives to our executives to increase the value of our stock over time. In addition, the vesting features of our equity grants contribute to executive retention by providing an incentive to our executives to remain employed with us during the vesting period.

Equity compensation represents the largest at-risk component of our NEOs’ compensation arrangements. We believe that it is appropriate to align the interests of our NEOs with those of our stockholders to achieve and sustain long-term stock price appreciation. We typically use stock option, RSU and PSU awards to compensate our NEOs in the form of initial grants in connection with the commencement of employment as well as on an annual basis. In addition, from time to time we have granted certain employees, including our NEOs, supplemental RSU and/or PSU awards in order to further promote retention and to motivate and recognize individual employees’ impact on our organizational success.

We grant equity awards to our NEOs with both time-based and performance-based vesting. The stock options that we grant to our NEOs with time-based vesting typically become exercisable as to 25% of the shares underlying the option on the first anniversary of the grant date, and as to the remaining shares in equal monthly increments over the 36 months thereafter. The RSUs we grant to our NEOs typically vest in equal annual

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installments on each anniversary of the date of grant, until the third anniversary of such date. The PSUs that we grant to our NEOs generally vest in connection with the achievement of specified company performance milestones. The exercise price of all stock options equals the fair market value of shares of our common stock on the date of grant. Prior to the exercise of an option, the holder has no rights as a stockholder with respect to the shares subject to such option, including no voting rights and no right to receive dividends or dividend equivalents. Vesting of stock options ceases on termination of service and the exercise rights of stock options cease shortly after termination of service except in the case of death or disability. Vesting of both RSU and PSU awards ceases upon termination of service.

In specified termination and change in control circumstances, equity awards held by our NEOs are subject to accelerated vesting. See “—Severance and Change in Control Benefits” below for further information.

Annual Equity Grants

Our board of directors, upon the recommendation of our compensation & people committee, determined that the 2025 annual equity award for our chief executive officer would be split approximately 40% in stock options, 20% in RSUs and 40% in PSUs based on grant date fair value. Our compensation & people committee determined that the mix for the 2025 annual equity grants to our NEOs (other than the chief executive officer) be split approximately as follows: 50% in stock options, 25% in RSUs and 25% in PSUs, based on grant date fair value, for such NEOs. This equity mix excludes supplemental grants made to Ms. Jones and Mr. Burns in February 2025 (which are described below under “Supplemental 2025 Equity Grants”). Dr. Viswanadhan commenced employment with the company in March 2025, and as a result did not receive annual stock option or RSU grants in 2025, but did receive an annual PSU award in 2025 in accordance with the terms of his employment agreement. For information regarding the equity grants received by Dr. Viswanadhan upon his commencement of employment, see “New Hire Equity Grants” below.

The compensation & people committee and board of directors determined that the equity mix for 2025 annual grants was appropriate to ensure that compensation remains tied to stock performance and achievement of meaningful corporate milestones (through stock options and PSUs) and promotes retention (via RSUs that vest over time to deliver equivalent value to stock options while using fewer authorized shares). As noted below under “—2026 Executive Compensation Decisions”, our compensation & people committee determined that annual equity awards for our NEOs, except for our chief executive officer, continue to be split approximately 50% in stock options, 25% in RSUs and 25% in PSUs, based on grant date fair value, for 2026, in order to closely align executive compensation with the achievement of meaningful corporate milestones. Our board of directors, upon the recommendation of our compensation & people committee, determined that the annual equity award for our chief executive officer would continue to be split approximately 40% in stock options, 20% in RSUs and 40% in PSUs based on grant date fair value, for 2026, in order to further emphasize the performance-based component.

None of our NEOs are currently party to an employment agreement that provides for an automatic award of equity grants, other than initial equity awards made in connection with the start of employment.

In determining the size of the annual stock option, RSU and PSU awards to our NEOs, our compensation & people committee, with the assistance from Aon, considers our company performance, individual performance, the potential for enhancing the creation of value for our stockholders, the amount of equity previously awarded to the NEOs and the vesting terms of such prior awards, the company’s broader organizational equity needs and overall dilution, as well as industry and peer group benchmark data. We evaluate our equity award program on an annual basis to ensure that it appropriately links to our long-term performance by aligning the interests of our executives and our stockholders, remains competitive with industry and peer benchmarks and is consistent with our overall equity needs and dilution levels. Annual equity awards are typically granted to our NEOs effective March 1 of the applicable year.

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In February 2025, our compensation & people committee (or our board of directors, upon recommendation of our compensation & people committee, with respect to our chief executive officer) approved annual equity incentive awards in the form of stock options, RSUs and PSUs, as applicable, to our NEOs, effective March 1, 2025, in the amounts set forth opposite their respective names in the table below. In the case of each award, these grants were based on the NEO’s existing equity incentive holdings, level of responsibility within our company, equity ownership in relation to the peer group benchmark, and the compensation & people committee’s assessment (or our board of directors’ assessment, in the case of our chief executive officer) of the NEO’s individual performance and our overall company performance, in each case without reference to any specific metric.

New Hire Equity Grants

In connection with the start of Dr. Viswanadhan’s employment on March 5, 2025, the compensation & people committee granted him equity awards in the form of stock options, RSUs and PSUs, as reflected in the table below. These awards were granted outside our 2023 Stock Incentive Plan, as amended, as inducements material to Dr. Viswanadhan’s entry into employment with us in accordance with Nasdaq Listing Rule 5635(c)(4), and were designed to be competitive with market practice.

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Supplemental 2025 Equity Grants

In addition to the annual equity grants outlined above, in February 2025, the compensation & people committee granted to Ms. Jones and Mr. Burns the RSUs set forth in the table below, effective March 1, 2025, in order to recognize their significant contribution to the company’s sale of the vorasidenib royalty rights in August 2024, which resulted in $905 million of upfront proceeds to the company and significantly strengthened the company’s balance sheet.

Performance Share Units (PSUs)

In addition to annual stock option and RSU grants, we grant PSUs to our executives, including our NEOs, in order to further align executive incentives with critical value drivers for the business. We have multiple PSU programs for our executives under which PSUs will vest only after the achievement of specified performance milestones, as described below. Beginning in 2022, our compensation & people committee formally introduced PSUs as part of the annual equity grants to our executives, including our NEOs. Our PSU program milestones for the past five years are summarized below.

2022 PSU Program

The PSUs that we granted to our then-current NEOs in 2022 (including to Ms. Jones upon commencement of her employment in 2022, and other than Mr. Goff), vest as to one-half of the underlying shares upon our compensation & people committee’s determination of the achievement of each of the following milestones, the performance period for which expires as set forth below:

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2022 PSU Awards to Chief Executive Officer

The PSUs that we granted to Mr. Goff in August 2022 in connection with his appointment as our chief executive officer vest as to the underlying shares upon our compensation & people committee’s determination of the achievement of each of the following milestones, the performance period and relative weight for each milestone as set forth below:

2023 PSU Program

The PSUs that we granted to our then-current NEOs in March 2023 vest as to one-half of the underlying shares upon our compensation & people committee’s determination of the achievement of each of the following milestones (which are also included in the milestones for Mr. Goff’s 2022 PSU awards, described above), with the performance period as set forth below:

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2024 PSU Program

The PSUs that we granted to our then-current NEOs in March 2024 vest as to the underlying shares upon our compensation & people committee’s determination of the achievement of each of the following milestones, the performance period and relative weight for each milestone as set forth below:

As part of Dr. Viswanadhan’s new hire equity awards granted in March 2025, he was granted PSUs with the same performance conditions as the PSUs under the 2024 PSU Program.

2025 PSU Program

The PSUs that we granted to our NEOs in March 2025 vest as to the underlying shares upon our compensation & people committee’s determination of the achievement of each of the following milestones, the performance period and relative weight for each milestone as set forth below:

2026 PSU Program

The PSUs that we granted to our NEOs in March 2026 vest as to the underlying shares upon our compensation & people committee’s determination of the achievement of each of the following milestones, the performance period and relative weight for each milestone as set forth below:

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We believe that PSUs further increase the performance orientation of our executive compensation program thereby leading to the compensation & people committee’s decision to formally include PSUs as part of the annual equity award mix for our executives. The PSU milestones are intended to align with a broad range of the most significant long-term value-creating objectives for the company.

2026 Executive Compensation Decisions

In February 2026, our compensation & people committee (or our board of directors, upon recommendation of the compensation & people committee, for our chief executive officer) approved 2026 base salaries, target annual performance-based cash incentive percentages and annual stock option, RSU and PSU awards for our NEOs. The table below sets forth the 2026 compensation levels for our NEOs.

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Supplemental 2026 Equity Grants

In addition to the annual equity grants outlined above, in February 2026, the compensation & people committee granted to Dr. Gheuens the RSUs set forth in the table below, effective March 1, 2026, in order to recognize her leadership and expertise through the Company’s regulatory review and approval of AQVESME^™ and RISE UP clinical trial data readout and continued excellence with regulatory interactions leading to a sNDA with accelerated review path for mitapivat in SCD.

Salary increases for 2026 became effective as of January 1, 2026. The annual cash incentive target award percentage for our NEOs remained unchanged from 2025. Annual performance-based cash incentive program payouts for 2026 annual cash incentives will be based on our performance against specific research, clinical, operational and financial company goals and, as stated above, will be capped at 150% of the target payout level.

In February 2026, our compensation & people committee determined that annual equity awards for our NEOs, with the exception of our chief executive officer, would be split approximately 50% in stock options, 25% in RSUs and 25% in PSUs, based on grant date fair value, for 2026, in order to closely align executive compensation with the achievement of meaningful corporate milestones. The compensation & people committee and board of directors determined that the grant of the annual equity award for our chief executive officer would be split approximately 40% in stock options, 20% in RSUs and 40% in PSUs based on grant date fair value, in order to further emphasize the performance-based component.

Severance and Change in Control Benefits

In 2016, our compensation & people committee adopted the Severance Benefits Plan, or the Severance Plan, which applies to our NEOs and certain other employees, and which became effective as of April 22, 2016 and was subsequently amended on October 6, 2022. The Severance Plan provides for severance benefits in the event of a termination of such NEO’s employment by us without cause or by such employee for good reason either (i) before or more than 18 months after a change in control, or Non-Change of Control Termination, or (ii) within 18 months following a change in control, or Change of Control Termination.

Please refer to “—Employment, Severance and Change in Control Arrangements” below for a more detailed discussion of severance and change in control benefits for our NEOs. We also have provided estimates of the value of the severance payments made and other benefits provided to our NEOs under specified termination circumstances under the caption “—Potential Payments Upon Termination or Change in Control” below. We believe that providing these benefits helps us compete for executive talent. These benefits are designed to promote stability and continuity of our senior management and are intended to preserve employee morale and productivity and encourage retention in the face of the disruptive impact of an actual, threatened, or rumored change in control of the company.

Health and Welfare Benefits

Our NEOs are eligible to participate in all of our employee benefit plans, including our medical, dental, vision, life and disability insurance plans, in each case on the same basis as other employees. We believe that

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these health and welfare benefits help ensure that we have a productive and focused workforce through reliable and competitive health and other benefits.

401(k) Retirement Plan

We maintain a 401(k)-retirement plan that is intended to be a tax-qualified defined contribution plan under Section 401(k) of the Internal Revenue Code, as amended, or the Code. In general, all of our employees are eligible to participate, beginning on the first day of the month following commencement of their employment. The 401(k) plan includes a salary deferral arrangement pursuant to which participants may elect to reduce their current compensation by up to the statutorily prescribed limit, equal to $23,500 in 2025, and have the amount of the reduction contributed to the 401(k) plan. Participants who turned age 50 in 2025 were also eligible to make “catch-up” contributions, which in 2025 were up to an additional $7,500 above the statutory limit. Participants who were ages 60 to 63 in 2025 were eligible for a higher catch-up contribution limit of $11,250 for 2025. In 2025, we matched 100% of employee 401(k) contributions up to the first 4% of eligible contributions. Matching contributions are 100% vested immediately.

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Compensation Committee Report

The compensation & people committee has reviewed and discussed the Compensation Discussion and Analysis required by Item 402(b) of Regulation S-K with our management. Based on this review and discussion, the compensation & people committee recommended to our board of directors that the Compensation Discussion and Analysis be included in this proxy statement.

This report of the compensation & people committee is not “soliciting material,” shall not be deemed “filed” with the SEC and shall not be incorporated by reference by any general statement incorporating by reference this proxy statement into any filing under the Securities Act or the Exchange Act, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing, except to the extent that we specifically incorporate this information by reference, and shall not otherwise be deemed filed under such acts.

The foregoing report has been furnished by the compensation & people committee.

Respectfully submitted,

The Compensation & People Committee of the Board of Directors

Cynthia Smith (chair)

Kaye Foster

Catherine Owen Adams

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Summary Compensation Table

The following table shows information regarding the compensation of our NEOs during the fiscal years ended December 31, 2025, 2024 and 2023.

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Grants of Plan-Based Awards for 2025

The following table sets forth information concerning each grant of an award made to a NEO during the fiscal year ended December 31, 2025 under any plan, contract, authorization or arrangement pursuant to which cash, securities, similar instruments or other property may be received. The cash awards were made under our annual performance-based cash incentive program. The new hire equity awards granted to Dr. Viswanathan in March 2025 were made outside of our 2023 Stock Incentive Plan, as amended, as inducements material to his entry into employment with us in accordance with Nasdaq Listing Rule 5635(c)(4). All of the other equity awards granted to our NEOs in 2025 were made under our 2023 Stock Incentive Plan, as amended. Each grant was authorized by our compensation & people committee, or board of directors, as applicable. For more information on equity acceleration benefits under specified circumstances, see “—Employment, Severance and Change in Control Arrangements.”

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