SAGE THERAPEUTICS, INC.

215 FIRST STREET

CAMBRIDGE, MA 02142

NOTICE OF 2024 ANNUAL MEETING OF STOCKHOLDERS

We invite you to attend the 2024 Annual Meeting of Stockholders, or the Annual Meeting, of Sage Therapeutics, Inc. (referred to as “we,” “us,” the “Company” or “Sage”) which will be held online via live webcast on Monday, June 10, 2024, at 8:30 a.m. Eastern Time. You may attend the meeting virtually via the Internet at www.virtualshareholdermeeting.com/SAGE2024, where you will be able to vote electronically. You will need the 16-digit control number included with these proxy materials to attend the Annual Meeting.

The purpose of the Annual Meeting is to take the following actions:

The Annual Meeting will be held over the Internet in a virtual meeting format, via live webcast. There will be no in-person meeting, and you will only be able to attend the Annual Meeting virtually via the webcast. Only our stockholders of record at the close of business on April 16, 2024, will be entitled to vote at the Annual Meeting and any adjournment or postponement thereof. A complete list of registered stockholders will be available at our principal executive offices during ordinary business hours for examination by any stockholder of record for a period of ten days ending on the day before the Annual Meeting.

We have elected to provide access to our proxy materials over the Internet under the Securities and Exchange Commission’s, or SEC’s, “notice and access” rules. On or about April 24, 2024, we will mail to our stockholders a Notice of Internet Availability of Proxy Materials, or Notice, containing instructions on how to access our proxy materials, including our proxy statement and our 2023 Annual Report to Stockholders, or 2023 Annual Report. We believe that providing our proxy materials over the Internet expedites stockholders’ receipt of proxy materials, lowers printing and distribution costs and reduces the environmental impact of the Annual Meeting. The Notice also instructs you on how to submit your proxy or voting instructions through the Internet.

The Notice also contains instructions on how to request a paper copy of our proxy materials and our 2023 Annual Report. Other stockholders, in accordance with their prior requests, have received e-mail access to our proxy materials and instructions to submit their vote via the Internet, or have been mailed paper copies of our proxy materials and a proxy card or voting instruction form.

Your vote is important. Whether or not you plan to participate in the virtual Annual Meeting, we hope you will take the time to vote your shares. To ensure that your vote is recorded promptly, please vote as soon as possible, even if you plan to attend the meeting.

By Order of the Board of Directors,

President, Chief Executive Officer and Director

April 24, 2024

TABLE OF CONTENTS

SAGE THERAPEUTICS, INC.

215 FIRST STREET

CAMBRIDGE, MA 02142

PROXY STATEMENT SUMMARY

The summary highlights certain information related to topics discussed throughout this Proxy Statement. This summary does not contain all of the information that you should consider, and you should read the entire Proxy Statement carefully before voting.

VIRTUAL ANNUAL MEETING INFORMATION

HOW TO VOTE

By Internet		By telephone		By mailing your Proxy Card		During the meeting
Visit 24/7 www.proxyvote.com		Dial toll-free 24/7 1-800-690-6903		Cast your ballot, sign your proxy card and send by free post		Vote during the live webcast of the Annual Meeting
You may vote by Internet 24 hours a day, seven days per week. You will need the 16-digit control number included on your Notice, proxy card or voting instruction form. Votes submitted through the Internet must be received by 11:59 p.m. Eastern Time on June 9, 2024.		You may vote using a touch-tone telephone by calling 24 hours a day, seven days a week. You will need the 16-digit control number included on your Notice, proxy card or voting instruction form. Votes submitted by telephone must be received by 11:59 p.m. Eastern Time on June 9, 2024.		If you received printed proxy materials, you may submit your vote by completing, signing and dating your proxy card or voting instruction form and returning it in the prepaid envelope. Proxy cards submitted by mail must be received no later than June 9, 2024.		You may vote during the Annual Meeting by going to: www.virtualshareholdermeeting.com/SAGE2024. You will need the 16-digit control number included on your Notice, proxy card or voting instruction form. If you previously voted via the Internet, by telephone, or by mail, that vote will not limit your right to vote online at the Annual Meeting.

If you plan to attend the Annual Meeting, we recommend that you visit the link for the live webcast at www.virtualshareholdermeeting.com/SAGE2024 and log in with your 16-digit control number prior to the start time of 8:30 a.m. Eastern Time to ensure you are fully logged in when the Annual Meeting begins. If you attend the Annual Meeting, you may vote your shares electronically during the Annual Meeting even if you have previously returned your proxy card or completed your proxy by phone or on the Internet. Stockholders wishing to vote their shares electronically during the Annual Meeting should refer to their Notice for instructions regarding voting electronically during the Annual Meeting.

A summary of the information you need to attend the Annual Meeting online is provided below:

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CAST YOUR VOTE RIGHT AWAY

Please cast your vote right away on all of the proposals listed below to ensure that your shares are represented.

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STOCKHOLDER ENGAGEMENT AND GOVERNANCE HIGHLIGHTS

Stockholder Engagement

We believe that effective corporate governance includes active and regular engagement with our stockholders, and we are committed to investing time with our stockholders to increase transparency and gain a better understanding of the practices our stockholders most value. We seek to conduct a robust year-round stockholder outreach program to solicit and understand our stockholders’ perspectives on our executive compensation, corporate governance and disclosure practices, among other matters. Our Board of Directors, the Compensation Committee of our Board of Directors, or our Compensation Committee, and the Nominating and Corporate Governance Committee of our Board of Directors, or our Nominating and Corporate Governance Committee, consider feedback received from this effort and other input from our stakeholders and advisors in determining what further governance and compensation actions, if any, are in the best interest of the Company and its stockholders. For example, in late 2023, we consulted several of our largest stockholders specifically to solicit their feedback about option exchange programs, including their perspectives on certain design elements being considered at that time for an option exchange program for our employees. We incorporated this feedback in our design of an option exchange program approved by our stockholders at a special meeting of stockholders held on January 31, 2024, and completed on February 21, 2024.

Between mid-2023 and early 2024, we solicited feedback from stockholders representing approximately 87% of our outstanding shares based on public filings as of December 31, 2023 and engaged with stockholders then representing approximately 67% of our outstanding shares to seek input on our corporate governance and compensation matters. The key topics discussed included executive compensation, board composition, and the option exchange program discussed above. We value the variety of perspectives we receive during these discussions and the opportunity they present to deepen our understanding of stockholder interests and explain our motivations and priorities with respect to our governance and compensation practices.

We intend to continue our stockholder outreach following the filing of this Proxy Statement with the SEC, to seek support for the Annual Meeting proposals and to solicit additional feedback regarding governance and compensation matters of importance to our stockholders, as well as following the Annual Meeting, regardless of the vote results on the proposals included herein.

Governance Highlights

We are committed to maintaining strong corporate governance practices and regularly reviewing our corporate governance practices to continue building on our success and long-term stockholder value. The highlights of our corporate governance practices include the following:

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Nominees for Class I Directors

The names of the nominees for Class I directors and certain information about each as of April 16, 2024, are set forth below.

We believe Ms. Barrett’s qualifications to sit on our Board of Directors include her executive and commercial launch experience and years of leadership in the pharmaceutical industry. We believe Mr. Germano’s qualifications to serve on our Board of Directors include his extensive leadership and operating experience in the pharmaceutical industry in multiple therapeutic categories and global markets at several pharmaceutical companies.

Executive Compensation Highlights

We have a pay-for-performance compensation philosophy, and as a result, we seek to align actual compensation levels for our executive officers, including our named executive officers, with the achievement of corporate goals and

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individual performance. We had a number of major accomplishments in 2023, including those identified in the table below, which factored into our performance assessment for the purposes of funding our annual bonus incentive plan, or the Annual Bonus Incentive Plan, for 2023 for all employees, including our named executive officers. Our business highlights are more fully discussed in the section of this Proxy Statement entitled “Executive Officer and Director Compensation—Compensation Discussion and Analysis.”

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SAGE THERAPEUTICS, INC.

PROXY STATEMENT

FOR THE 2024 ANNUAL MEETING OF STOCKHOLDERS

GENERAL INFORMATION ABOUT THE ANNUAL MEETING AND VOTING

When are this Proxy Statement and the accompanying materials scheduled to be sent to stockholders?

Pursuant to rules adopted by the SEC, we have elected to provide access to our proxy materials to our stockholders via the Internet. Accordingly, on or about April 24, 2024, we will begin mailing a Notice of Internet Availability of Proxy Materials, or Notice, to our stockholders (other than those who previously requested electronic or paper delivery of proxy materials), directing stockholders to a website where they can access our proxy materials, including this Proxy Statement and our 2023 Annual Report, and view instructions on how to vote online or by telephone. Our proxy materials, including the Notice, this Proxy Statement and the accompanying proxy card or, for shares held in “street name” (held for your account by a broker or other nominee), a voting instruction form, and the 2023 Annual Report, will be mailed or made available to stockholders on the Internet on the same date. All stockholders will have the ability to access the proxy materials on the website referred to in the Notice or request to receive a printed set of the proxy materials. Instructions on how to access the proxy materials over the Internet or to request a printed copy may be found in the Notice.

Why did I receive a Notice of Internet Availability of Proxy Materials instead of a full set of proxy materials?

Pursuant to rules adopted by the SEC, we are providing access to our proxy materials for most stockholders over the Internet rather than printing and mailing our proxy materials. We believe following this process will expedite the receipt of such materials and will help lower our costs and reduce the environmental impact of our annual meeting materials. Therefore, the Notice will be mailed to holders of record and beneficial owners of our common stock starting on or about April 24, 2024. The Notice will provide instructions as to how stockholders may access and review our proxy materials, including this Proxy Statement, the proxy card and our 2023 Annual Report, on the website referred to in the Notice or, alternatively, how to request that a copy of the proxy materials, including a proxy card, be sent to a requesting stockholder by mail. The Notice will also provide voting instructions. In addition, stockholders of record may request to receive the proxy materials in printed form by mail or electronically by e-mail on an ongoing basis for future stockholder meetings. Please note that, while our proxy materials are available at the website referenced in the Notice, and our Notice of the 2024 Annual Meeting of Stockholders, this Proxy Statement and our 2023 Annual Report are available on our website, no other information contained on either website is incorporated by reference in or considered to be a part of this Proxy Statement.

Where and when is the Annual Meeting?

The Annual Meeting will be held on Monday, June 10, 2024 at 8:30 a.m. Eastern Time. To afford the same rights and opportunities to participate in the Annual Meeting to all stockholders irrespective of location, the Annual Meeting will be held in a virtual meeting format only, via live webcast on the Internet, with no physical in-person meeting. A summary of the information you need to attend the Annual Meeting online is provided below:

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If you plan to attend the Annual Meeting, we recommend that you visit the link for the live webcast at www.virtualshareholdermeeting.com/SAGE2024 and log in with your 16-digit control number prior to the start time of 8:30 a.m. Eastern Time to ensure you are fully logged in when the Annual Meeting begins. If you attend the Annual Meeting, you may vote your shares electronically during the Annual Meeting even if you have previously returned your proxy card or completed your proxy by phone or on the Internet. Stockholders wishing to vote their shares electronically during the Annual Meeting should refer to their Notice for instructions regarding voting electronically during the Annual Meeting.

What do I need in order to be able to participate in the Annual Meeting online?

You will need the 16-digit control number included on your Notice or your proxy card in order to be able to access the Annual Meeting and vote your shares or submit questions during the Annual Meeting.

What if during the Annual Meeting I have technical difficulties or trouble accessing the live webcast of the Annual Meeting?

If you encounter any technical difficulties or trouble accessing the live webcast of the Annual Meeting or other technical issues during the Annual Meeting, please call the technical support number that will be posted on the log-in page for our virtual Annual Meeting for assistance.

Who is soliciting my vote?

Our Board of Directors is soliciting your vote for the Annual Meeting.

When is the record date for the Annual Meeting?

The record date for determination of stockholders entitled to vote at the Annual Meeting is the close of business on April 16, 2024.

How many votes can be cast by all stockholders?

There were 60,182,031 shares of our common stock, par value $0.0001 per share, outstanding on April 16, 2024, all of which are entitled to vote with respect to all matters to be acted upon at the Annual Meeting. Each stockholder of record is entitled to one vote for each share of our common stock held by such stockholder. We had no shares of preferred stock outstanding as of April 16, 2024.

How do I vote?

You may vote your shares over the Internet, by telephone or during the Annual Meeting by going to www.virtualshareholdermeeting.com/SAGE2024. If you requested and/or received a printed version of the proxy card, you may also vote by mail.

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Voting deadlines and availability of telephone and Internet voting for beneficial owners whose shares are held in street name by a bank, broker or nominee depend on the voting processes of the entity that holds their shares. If your shares are held in street name, we urge you to carefully review and follow the voting instruction form and any other materials that you might receive from the entity that is the record holder of your shares. If your shares are held in street name and your voting instruction form indicates that you may vote those shares through the http://www.proxyvote.com website, then you may join the Annual Meeting with the 16-digit access code indicated on that voting instruction form. Otherwise, stockholders who hold their shares in street name should contact their bank, broker or nominee (preferably at least 5 business days before the Annual Meeting) and obtain a “legal proxy” in order to be able to join the Annual Meeting.

If you complete and submit your proxy before the Annual Meeting, the persons named as proxies will vote the shares represented by your proxy in accordance with your instructions. If you submit a proxy without giving voting instructions, your shares will be voted in the manner recommended by the Board of Directors on all matters presented in this Proxy Statement, and as the persons named as proxies may determine in their discretion with respect to any other matters properly presented at the Annual Meeting. You may also authorize another person or persons to act for you as proxy in writing, signed by you or your authorized representative, specifying the details of those proxies’ authority. The original writing must be given to each of the named proxies, although it may be sent to them by electronic transmission if, from that transmission, it can be determined that the transmission was authorized by you.

If any other matters are properly presented for consideration at the Annual Meeting, including, among other things, consideration of a motion to adjourn the Annual Meeting to another time or place (including, without limitation, for the purpose of soliciting additional proxies), the persons named in your proxy and acting thereunder will have discretion to vote on those matters in accordance with their best judgment. We do not currently anticipate that any other matters will be raised at the Annual Meeting.

How do I revoke my proxy?

If your shares are registered directly in your name, you may revoke your proxy and change your vote at any time before the Annual Meeting. To do so, you must do one of the following:

If a broker, bank, or other nominee holds your shares, you must contact such broker, bank, or nominee in order to find out how to change your vote.

How is a quorum reached?

Our Amended and Restated Bylaws, or Bylaws, provide that a majority of the shares entitled to vote, present at the Annual Meeting or represented by proxy, will constitute a quorum for the transaction of business at the Annual Meeting.

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Your shares will be counted towards the quorum only if you submit a valid proxy (or one is submitted on your behalf by your brokerage firm, bank, dealer or other agent) or if you vote online during the Annual Meeting. Under the General Corporation Law of the State of Delaware, or the DGCL, shares that are voted “abstain” or “withheld” and, in specified circumstances, broker “non-votes” are counted as present for purposes of determining whether a quorum is present at the Annual Meeting. If there is no quorum, the holders of a majority of shares present by virtual attendance at the Annual Meeting or represented by proxy may adjourn the Annual Meeting to another date.

How is the vote counted?

In accordance with our Bylaws, directors are elected by a plurality of the votes properly cast by the stockholders entitled to vote on the election of directors at the Annual Meeting. Under our Bylaws, any proposal other than an election of directors is decided by a majority of the votes properly cast for and against such proposal, except where a larger vote is required by law or by our Amended and Restated Certificate of Incorporation, or Certificate of Incorporation, or our Bylaws. Therefore, at the Annual Meeting, the two nominees receiving the most votes FOR election will be elected as directors (Proposal 1), and each other proposal will be approved if a majority of the votes properly cast are voted FOR the proposal (Proposals 2, 3, and 4). Abstentions and broker “non-votes” are not included in the tabulation of the voting results on any such proposal and, therefore, do not have an impact on such proposals. A broker “non-vote” occurs when a nominee holding shares for a beneficial owner does not vote on a particular proposal because the nominee does not have or did not exercise discretionary voting power with respect to that matter or has not received instructions from the beneficial owner.

If your shares are held in street name by a brokerage firm, your brokerage firm is required to vote your shares according to your instructions. If you do not give instructions to your brokerage firm, the brokerage firm will still be able to vote your shares with respect to “discretionary” matters but will not be allowed to vote your shares with respect to “non-discretionary matters.” Proposals 1, 3, and 4 are non-discretionary matters. If you do not instruct your broker how to vote with respect to those proposals, your broker may not vote for those proposals, and those votes will be counted as broker “non-votes.” Proposal 2 is considered to be a discretionary matter, and your brokerage firm will be able to vote on this proposal even if it does not receive instructions from you.

Who pays the cost for soliciting proxies?

We are making this solicitation and will pay the entire cost of preparing and distributing the Notice and our proxy materials and soliciting votes. If you choose to access the proxy materials or vote over the Internet, you are responsible for any Internet access charges that you may incur. Our officers and employees may, without compensation other than their regular compensation, solicit proxies through further mailings, personal conversations, facsimile transmissions, e-mails, or otherwise. Proxy solicitation expenses that we will pay include those for preparation, mailing, returning, and tabulating the proxies. We have engaged Alliance Advisors to assist in the solicitation of proxies and provide related advice and informational support, for a services fee, plus customary expense disbursements, which are not expected to exceed $18,500 in total.

How are matters submitted for consideration at an annual meeting?

Stockholder proposals intended to be presented at the next annual meeting of our stockholders after the upcoming Annual Meeting must satisfy the requirements set forth in the advance notice provisions under our Bylaws. To be timely for our next annual meeting of stockholders, any such proposal must be delivered in writing to our Secretary at 215 First Street, Cambridge, Massachusetts 02142 between the close of business on February 10, 2025, and March 12, 2025. If the next annual meeting of the stockholders is scheduled to take place before May 11, 2025, or after August 9, 2025, notice by the stockholder must be delivered no later than the close of business on the later of (1) the 90th day prior to such annual meeting or (2) the 10th day following the day on which public announcement of the date of such meeting is first made. Stockholders are advised to review our bylaws which also specify requirements as to the form and content of a stockholder’s notice, including the information required by Rule 14a-19 under the Exchange Act.

In addition, any stockholder proposal intended to be included in the proxy statement for the next annual meeting of our stockholders in 2025 must satisfy the requirements of Rule 14a-8 under the Exchange Act and be received not later than December 25, 2024. If the date of such annual meeting is moved by more than 30 days from the date contemplated at the time of the previous year’s proxy statement, then notice must be received within a reasonable time

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before we begin to print and send proxy materials. If that happens, we will publicly announce the deadline for submitting a proposal in a press release or in a document filed with the SEC.

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 each Notice to ensure that all of your shares are voted.

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

Preliminary voting results will be announced at the Annual Meeting. In addition, final voting results will be published in a current report on Form 8-K that we expect to file with the SEC within four business days after the Annual Meeting.

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OVERVIEW OF PROPOSALS

This Proxy Statement contains four proposals requiring stockholder action, which are as follows:

Each of the above proposals is discussed in more detail in the pages that follow.

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PROPOSAL 1

ELECTION OF DIRECTORS

The Board of Directors is divided into three classes. One class is elected each year at the annual meeting of stockholders for a term of three years. Vacancies on the Board of Directors may be filled exclusively by the affirmative vote of a majority of the remaining directors, even if less than a quorum of the Board of Directors, and may not be filled by holders of our common stock. A director elected by the Board of Directors to fill a vacancy in a class shall hold office for the remainder of the full term of that class, and until the director’s successor is duly elected and qualified or until his or her earlier death, resignation, or removal.

The terms of the Class I directors are scheduled to expire on the date of the upcoming Annual Meeting. Based on the recommendation of our Nominating and Corporate Governance Committee, the Board of Directors’ nominees for election by the stockholders are the following current Class I members: Elizabeth Barrett and Geno Germano. If elected, each nominee will serve as a director until the annual meeting of stockholders in 2027 and until his or her successor is duly elected and qualified, or until his or her earlier death, resignation, or removal.

Steven Paul, M.D. has notified the Board of Directors of his intention to retire from the Board of Directors when his current term ends at the Annual Meeting. Dr. Paul’s decision is not the result of any disagreement with us on any matter relating to our operations, policies or practices. In connection with his retirement, the authorized number of directors on the Board of Directors will be reduced from nine to eight and the number of Class I directors will be reduced from three to two.

The names of and certain information about the directors in each of the three classes are set forth below.

It is intended that proxies will be voted, unless otherwise indicated, for the election of the Class I director nominees to the Board of Directors. Each of the nominees has indicated his or her willingness to serve as a Class I director if elected. We have no reason to believe that any nominee will be unable to serve. If any of the nominees should for any reason be unable or unwilling to serve at any time prior to the Annual Meeting, however, the proxies may be voted for the election of such substitute nominee as the Board of Directors may designate.

Nominees for Class I Directors

The names of the nominees for Class I directors and certain information about each as of April 16, 2024, are set forth below.

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Directors Not Up for Election at the Annual Meeting

The names of and certain information as of April 16, 2024, about the members of the Board of Directors who are not standing for re-election at this year’s Annual Meeting are set forth below.

Biographical Information Concerning Our Board of Directors

Set forth below are the biographies of each director, as well as a discussion of the particular experience, qualifications, attributes, and skills that led our Board of Directors to conclude that each person nominated to serve or currently serving on our Board of Directors should serve as a director. In addition to the information presented below, we believe that each director meets the minimum qualifications established by the Nominating and Corporate Governance Committee for our directors.

Elizabeth (Liz) Barrett. Ms. Barrett has served as a member of our Board of Directors since January 2019. Ms. Barrett has served as President and Chief Executive Officer and a board member of UroGen Pharma Ltd., a commercial-stage biopharmaceutical company since January 2019. She previously served as Chief Executive Officer of Novartis Oncology, or Novartis, from February to December 2018. Prior to Novartis, she was Global President, oncology at Pfizer Inc., or Pfizer, from 2015 to 2018. From 2009 to 2015, she held a series of leadership positions at Pfizer, including President, Europe, Global Innovative Pharma, President, North America, and President, U.S. Oncology business unit. Prior to Pfizer, from 2006 to 2009, Ms. Barrett was Vice President and General Manager of the Oncology business unit at Cephalon Inc. She also held senior roles across multiple market sectors at Johnson & Johnson from 1993 to 2006. In addition, Ms. Barrett has served as a member of the board of directors of Allogene Therapeutics, Inc., a public clinical stage immune-oncology company, since July 2021. Ms. Barrett received a B.S. from the University of Louisiana and an M.B.A. from Saint Joseph’s University. We believe Ms. Barrett’s qualifications to sit on our Board of Directors include her executive experience and years of leadership in the pharmaceutical industry.

Michael F. Cola. Mr. Cola has served as a member of our Board of Directors since September 2014. Mr. Cola has served as an advisor for Yale Ventures since October 2022 and an advisor for Mayo Ventures since June 2022. He served as Chief Executive Officer and a board member of Avalo Therapeutics, Inc. (formerly Cerecor, Inc.), or Avalo, a biopharmaceutical company, from February 2020 to February 2022. Prior to Avalo, Mr. Cola served as Chief Executive Officer of Aevi Genomic Medicine, Inc., or Aevi, a biopharmaceutical company formerly named Medgenics, Inc. from 2013 to February 2020. Prior to joining Aevi, from 2005 to 2012, he served as president of specialty pharmaceuticals at Shire plc, or Shire, a global specialty pharmaceutical company. Previously, from 2000 to 2005, Mr. Cola served as a Growth Capital Provider and President of the life sciences group for Safeguard Scientifics, Inc., where he served as Chairman and Chief Executive Officer of Clarient, Inc., and Chairman of Laureate Pharma, Inc. In addition, Mr. Cola has held senior positions in product development and commercialization at Astra Merck Inc., where he led Phase 2 through Phase 4 clinical development efforts, and at AstraZeneca plc., where he led clinical development worldwide. He also currently serves on the board of directors of Phathom Pharmaceuticals, Inc., a late-stage biopharmaceutical company. Mr. Cola received a B.A. in biology and physics from Ursinus College and an M.S. in biomedical science from Drexel University. We believe Mr. Cola’s qualifications to sit on our Board of Directors include his extensive experience working for various pharmaceutical and biotechnology companies.

James M. Frates. Mr. Frates has served as a member of our Board of Directors since May 2014. Since January 2021, Mr. Frates has served as the Chief Financial Officer of Amylyx Pharmaceuticals, Inc., a pharmaceutical company focused on developing new treatments for amyotrophic lateral sclerosis (ALS), Alzheimer’s disease and other

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neurodegenerative diseases. Mr. Frates previously served as Senior Vice President and Chief Financial Officer of Alkermes plc from September 2011 until January 2021. From 2007 to 2011, Mr. Frates served as Senior Vice President and Chief Financial Officer of Alkermes, Inc. From 1998 to 2007, Mr. Frates served as Vice President, Chief Financial Officer and Treasurer of Alkermes, Inc. From 1992 to 1994 and 1996 to 1998, he was employed at Robertson, Stephens & Company, most recently as a Vice President in Investment Banking. Prior to that time, he was employed at Morgan Stanley & Co. Mr. Frates earned an A.B. in government from Harvard College and an M.B.A. from Harvard Business School. We believe Mr. Frates’ qualifications to sit on our Board of Directors include his leadership experience, financial expertise, business judgment and industry knowledge.

Geno Germano. Mr. Germano has served as the Chair of our Board of Directors since January 2024 and as a member of our Board of Directors since July 2016. Since August 2018, Mr. Germano has served as President and Chief Executive Officer and a board member of Elucida Oncology, Inc., a biotechnology company. He previously served as President of Intrexon Corporation, or Intrexon, a leader in engineering and industrialization of biology, from June 2016 to March 2017. Prior to joining Intrexon, from 2014 to February 2016, Mr. Germano was Group President of the Global Innovative Pharma Business of Pfizer, where he led a growing global $14 billion business with market-leading medicines and an extensive portfolio of late-stage development candidates in several therapeutic areas. Mr. Germano was also Co-Chair of the Portfolio Strategy and Investment Committee at Pfizer from 2013 to February 2016. Previously, from 2009 through 2013, Mr. Germano served as President and General Manager of Pfizer’s Specialty Care and Oncology business units where he led commercial, medical, and post proof-of-concept pipeline strategy and development across global markets. Additionally, Mr. Germano has served on the board of directors of Precision Biosciences, Inc., a clinical stage biotechnology company, since March 2020, and in the past five years, Mr. Germano served on the boards of directors of Bioverativ Inc. (acquired by Sanofi S.A. in March 2018) and The Medicines Company (acquired by Novartis AG in January 2020). Mr. Germano received his B.S. in Pharmacy from Albany College of Pharmacy. We believe Mr. Germano’s qualifications to serve on our Board of Directors include his over 30 years of experience in the pharmaceutical industry and his consistent track record of improving operating performance and increasing shareholder value, including across numerous leadership roles in multiple therapeutic categories and global markets at several pharmaceutical companies.

George S. Golumbeski, Ph.D. Dr. Golumbeski has served as a member of our Board of Directors since January 2019. Since October 2020, Dr. Golumbeski has served as a partner at DROIA Ventures, a venture capital firm focused on therapeutics for oncology and genetic disease, and previously served as the President of GRAIL, Inc., a health-care company focused on the early detection of cancer, from August 2018 to September 2019. From 2009 to April 2018, Dr. Golumbeski was employed by Celgene Corporation, or Celgene, as Executive Vice President of Business Development. Prior to Celgene, Dr. Golumbeski was Vice President of Business Development, Licensing, and Strategy at Novartis. Earlier in his career, he held leadership positions at Elan Pharmaceuticals Inc. and Schwarz Pharma AG, where he focused on neurology and neuropsychiatry therapeutics. Dr. Golumbeski has served on the boards of directors of Shattuck Labs, Inc., a public clinical-stage biotechnology company focused on cancer and autoimmune disease, since January 2018 and MorphoSys AG, a public commercial-stage biopharmaceutical company focused on cancer, since May 2018. He previously served on the board of directors of Enanta Pharmaceuticals, Inc., a public clinical stage biotechnology company focused on viral infections from February 2014 through March 2021. He also serves on the boards of directors of various private companies. Dr. Golumbeski received a B.A. in Biology from the University of Virginia and a Ph.D. in Genetics from the University of Wisconsin—Madison. We believe Dr. Golumbeski’s qualifications to sit on our Board of Directors include his years of experience in research and development, business development and leadership at various pharmaceutical companies.

Barry E. Greene. Mr. Greene has served as our Chief Executive Officer and President since December 2020 and as a member of our Board of Directors since October 2020. Mr. Greene served as President of Alnylam Pharmaceuticals, Inc., or Alnylam, a public biopharmaceutical company, from 2007 through September 2020, and served as its Chief Operating Officer from 2003 to September 2016. Prior to Alnylam, he was General Manager of Oncology at Millennium Pharmaceuticals, Inc., a public biopharmaceutical company. Prior to joining Millennium in 2001, Mr. Greene served as Executive Vice President and Chief Business Officer for Mediconsult.com, a healthcare consulting company. Prior to joining Mediconsult.com, Mr. Greene’s experience included serving as Vice President of Marketing and Customer Services for AstraZeneca (formerly AstraMerck), a pharmaceutical company; Vice President, Strategic Integration with responsibility for the AstraZeneca North American post-merger integration; and a partner of Andersen Consulting, a consulting company. Mr. Greene has served as a member of the board of directors of Karyopharm Therapeutics, Inc., since 2013 and previously served as a member of the boards of directors of Acorda Therapeutics, Inc., a public

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biotechnology company focused on nervous system disorders, from January 2007 to August 2021 and BCLS Acquisition Corporation, a former special purpose acquisition company, from October 2020 to October 2022. Mr. Greene received his B.S. in Industrial Engineering from the University of Pittsburgh and served as a Senior Scholar at Duke University’s Fuqua School of Business. We believe Mr. Greene’s qualifications to sit on our Board of Directors include his extensive experience and leadership in the healthcare and biopharmaceutical industries, including his experience serving as Chief Executive Officer at Sage.

Jeffrey M. Jonas, M.D. Dr. Jonas has served as a member of our Board of Directors since August 2013. Dr. Jonas is a partner at Cure Ventures, a life sciences venture capital firm. Prior to joining Cure Ventures in 2024, Dr. Jonas served as Chief Executive Officer and a Director of ABio-X, a private biotechnology incubator from November 2022 to January 2024. From December 2020 to November 2022, Dr. Jones served as our Chief Innovation Officer. Prior to assuming his role as Chief Innovation Officer, he had served as our President and Chief Executive Officer from August 2013 to December 2020. From 2012 to 2013, Dr. Jonas served as the President of the Regenerative Medicine Division of Shire, and from 2008 to 2012 as Senior Vice President of Research and Development, Pharmaceuticals at Shire. Dr. Jonas served from 2007 to 2008 as the Executive Vice President of Ionis Pharmaceuticals, Inc., formerly known as ISIS Pharmaceuticals, Inc.; from 2006 to 2007 as Chief Medical Officer and Executive Vice President of Forest Laboratories, Inc.; and from 1991 to 1996 in senior-level positions at Upjohn Laboratories. Dr. Jonas also founded AVAX Technologies, Inc. and SCEPTOR Industries, Inc., where he served as the Chief Executive Officer, President and a Director. Dr. Jonas currently serves on the board of directors of Generation Bio Co., a public biotechnology company, and Noema Pharma AG, a private biotechnology company. Dr. Jonas also served on the board of directors of Karuna Therapeutics, Inc., or Karuna, a public biopharmaceutical company, from October 2018 until its acquisition by Bristol Myers Squibb in March 2024. Dr. Jonas has authored more than 200 books, provided guidance on scientific articles and abstracts, and has received numerous awards. Dr. Jonas received his B.A. from Amherst College and M.D. from Harvard Medical School. He completed a residency in psychiatry at Harvard Medical School, and he served as Chief Resident in psychopharmacology at McLean Hospital, Harvard Medical School. We believe Dr. Jonas’ qualifications to serve on our Board of Directors include his over 20 years of experience on both the scientific and business sides of the pharmaceutical and healthcare industries, particularly in the central nervous system field, including his past experience serving as Chief Executive Officer and Chief Innovation Officer at Sage.

Jessica J. Federer. Ms. Federer has served as a member of our Board of Directors since March 2023. Ms. Federer has served as a senior external advisor for McKinsey & Company since January 2024. She previously served as a Partner at Boston Millennia Partners, an investment fund focused on health technology companies, from May 2017 to September 2022. Ms. Federer also served as Chief Digital Officer at Bayer A.G. from October 2014 to January 2017, and in other leadership roles in regulatory affairs, market access, communications, and public affairs at Bayer A.G. beginning in 2008. She has served on the board of Aspivix SA, a private medical device company based in Switzerland, since December 2023, and as a board member of Pluto Health, a private health tech company, since September 2022. She has also served as an investment advisory board member of the Blavatnik Fund at Yale Ventures, since August 2023; a board member of Angelini Ventures, based out of Rome, Italy, since April 2022; and as a member of the Yale Institutional Review Board for oncology since December 2021. Ms. Federer served on the United Nations International Telecommunication Union (ITU) advisory board from July 2016 to July 2018. She began her public health career as an analyst at the Agency for Healthcare Research and Quality in the U.S. Department of Health and Human Services. Ms. Federer received a B.S. from the George Washington University and a M.P.H. from Yale University. We believe Ms. Federer’s qualifications to sit on our Board of Directors include her extensive experience and leadership in the life sciences industry and track record of using technology to help improve access and care.

Vote Required and Board of Directors’ Recommendation

Directors will be elected by a plurality of the votes cast by the stockholders entitled to vote on this proposal at the Annual Meeting, which means that the two nominees receiving the most votes FOR election will be elected. Broker non-votes will not affect the outcome of the election, and proxies marked to withhold authority with respect to one or more nominees will not affect the outcome of the election for such nominees.

The proposal for the election of directors relates solely to the election of two Class I directors nominated by our Board of Directors.

Our Board of Directors recommends that stockholders vote “FOR” the election of each of the Class I director nominees listed above.

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CORPORATE GOVERNANCE

Board and Committee Matters

Board Leadership and Independence. Our Board of Directors has determined that all members of the Board of Directors, except Mr. Greene and Dr. Jonas, are independent, as determined in accordance with the rules of Nasdaq. In making such independence determination, the Board of Directors considered the relationships that each such non-employee director has with us and all other facts and circumstances that the Board of Directors deemed relevant in determining his or her independence, including the beneficial ownership of our common stock by each non-employee director. In considering the independence of our directors, our Board of Directors considered the association of our directors with the holders of more than 5% of our common stock. There are no family relationships among any of our directors or executive officers.

The positions of our Chair of the Board of Directors, or Chair of the Board, and Chief Executive Officer are presently separated. Separating these positions 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. Our Board of Directors recognizes the time, effort and energy that the Chief Executive Officer must devote to the position, as well as the commitment required to serve as the Chair of the Board, particularly as the Board of Directors’ oversight responsibilities continue to grow. Our Board of Directors also believes that this structure ensures a greater role for the non-management directors in the oversight of the Company and active participation of the independent directors in setting agendas and establishing priorities and procedures for the work of our Board of Directors. Our Board of Directors believes its administration of its risk oversight function has not been affected by its leadership structure. Although our Bylaws do not require our Chair of the Board and Chief Executive Officer positions to be separate, our Board of Directors believes that having separate positions is the appropriate leadership structure for us at this time.

Classified Board Structure. Our Board of Directors currently consists of nine members and is currently divided into three classes with Class I consisting of three directors, Class II consisting of two directors and Class III consisting of four directors. In connection with Dr. Paul’s retirement, the authorized number of directors on the Board of Directors will be reduced from nine to eight and the number of Class I directors will be reduced from three to two. Each class has a three-year term. At each annual meeting of our stockholders, the successors to directors whose terms then expire will be elected to serve from the time of election until the third annual meeting following the election. Any additional directorships resulting from an increase in the number of directors will be distributed among the three classes so that, as nearly as possible, each class will consist of one-third of our directors. Vacancies on our Board of Directors may be filled only by persons elected by a majority of the remaining directors. A director elected by the Board of Directors to fill a vacancy in a class, including vacancies created by an increase in the number of directors, shall serve for the remainder of the full term of that class and until the director’s successor is duly elected and qualified or his or her earlier resignation or removal.

Our Nominating and Corporate Governance Committee and our Board of Directors continue to believe that our classified board structure remains in the best interests of our business and our stockholders, and a prudent protection for a company of our size and stage of development, for the following key reasons:

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Notably, as of the date of our last assessment of the board structure of our peers in March 2023, over 75% of the companies in our 2023 Peer Group, which is described below under “Executive Officer and Director Compensation – Compensation Discussion and Analysis,” had classified boards. Our Board of Directors will continue to periodically assess the value of a classified Board to determine whether it remains in the best interests of our business and our stockholders.

Plurality Voting. Pursuant to our Bylaws, directors are elected by a plurality of the votes properly cast by the stockholders entitled to vote on the election of directors at each annual meeting of stockholders. This means that the nominees who receive the greatest number of votes are elected. Our Nominating and Corporate Governance Committee seeks to nominate directors that serve the best interests of our business and our stockholders. Our Board of Directors believes that plurality voting is in our best interests and the best interests of our stockholders because it avoids the possible consequences of a “failed election,” such as an unanticipated vacancy that could impact our ability to comply with applicable Nasdaq listing standards or securities laws with respect to committee composition or director independence, by significantly increasing the likelihood that all open positions up for election are filled at each director election.

We believe stockholders continue to have a strong voice in our director elections. Stockholders may use the “withhold” vote as a means to communicate dissatisfaction with a director nominee or our Board of Directors as a whole. For example, in 2021, in direct response to stockholder feedback regarding director commitments, including by way of withholding majority support for a director nominee, our Nominating and Corporate Governance Committee determined that, going forward, in the event that any director nominee were to receive less than majority stockholder support at a Sage annual meeting of stockholders as an apparent result of his or her number of other board memberships, our Board of Directors would evaluate the director nominee’s other commitments and assess his or her ability to dedicate the requisite time and attention to our business in order to effectively fulfill his or her responsibilities as a member of our Board of Directors.

Over 75% of companies in our 2023 Peer Group used plurality voting as of the date of our last assessment of peer company voting standards in March 2023. Our Board of Directors will continue to periodically assess the value of plurality voting and remains open to stockholder feedback on this matter.

Supermajority Voting Standards in Governing Documents. As required by the DGCL, any amendment of our Certificate of Incorporation must first be approved by a majority of our Board of Directors, and if required by law or our Certificate of Incorporation, must thereafter be approved by a majority of the outstanding shares entitled to vote on the amendment. An amendment to our Certificate of Incorporation relating to stockholder actions, provisions concerning the structure and composition of our Board of Directors, limitation of liability and additional amendments to our Certificate of Incorporation must be approved by not less than 75% of the outstanding shares entitled to vote on the amendment. Our Bylaws may be amended (i) by the affirmative vote of a majority of the directors then in office, subject to any limitations set forth in our Bylaws, (ii) by the affirmative vote of at least 75% of the outstanding shares entitled to vote on the amendment, or (iii) if the Board of Directors recommends that the stockholders approve the amendment, by the affirmative vote of the majority of the outstanding shares entitled to vote on the amendment. In addition, our Certificate of Incorporation provides that directors may be removed only for cause and then only by the affirmative vote of the holders of 75% or more of the shares then entitled to vote at an election of directors.

Our Board of Directors continues to believe that the supermajority voting standards in our Certificate of Incorporation and Bylaws are in the best interests of the Company and stockholders. These standards ensure that a large majority of stockholders are in alignment with any stockholder action to change our fundamental corporate documents or remove a director. In addition, supermajority voting standards can help safeguard the business against potentially unfair or

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hostile third-party takeover attempts, encouraging potential acquirors to communicate with our Board of Directors, who may then consider appropriate alternatives and maximize stockholder value for all stockholders.

As of the date of our last assessment in March 2023, all but one company in our 2023 Peer Group had supermajority voting standards for fundamental corporate changes. Our Board of Directors will continue to periodically assess the value of these standards to stockholder value.

Board Meetings and Committees. Our Board of Directors held ten meetings during 2023. The directors regularly hold executive sessions comprised of only independent directors at meetings of the Board of Directors. During 2023, none of our directors then in office attended less than 75% of the aggregate of all meetings of the Board of Directors and all meetings of the committees of our Board of Directors on which such director then served. Continuing directors and nominees for election as directors in a given year are required to attend the annual meeting of our stockholders, barring significant commitments or special circumstances. All of our then-current directors attended the 2023 annual meeting of stockholders.

Our Board of Directors currently has four standing committees: Audit Committee, Compensation Committee, Nominating and Corporate Governance Committee, and Science and Technology Committee.

Audit Committee. The current members of the Audit Committee of our Board of Directors, or our Audit Committee, are Elizabeth Barrett, Jessica J. Federer, and James M. Frates. Mr. Frates serves as the Chair of the Audit Committee. Michael F. Cola previously served as a member of the Audit Committee until January 2024, at which time our Board of Directors appointed Ms. Federer to serve on the Audit Committee. Our Board of Directors has determined that each member of the Audit Committee is independent for Audit Committee purposes as that term is defined in the rules of the SEC and the applicable Nasdaq rules, and has sufficient knowledge in financial and auditing matters to serve on the Audit Committee. Our Board of Directors has designated James M. Frates as an “Audit Committee financial expert,” as defined under the applicable rules of the SEC.

The Audit Committee’s responsibilities include:

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The Audit Committee held four meetings during 2023. The Audit Committee operates under a written charter that satisfies the applicable standards of the SEC and Nasdaq. A copy of the Audit Committee charter is available on our website at http://investor.sagerx.com/corporate-governance.

Compensation Committee. The current members of the Compensation Committee of our Board of Directors are Elizabeth Barrett, James M. Frates and Michael F. Cola. Mr. Cola serves as the Chair of the Compensation Committee. Our Board of Directors has determined that each member of the Compensation Committee is “independent” as defined in the applicable Nasdaq rules.

The Compensation Committee’s responsibilities include:

The Compensation Committee held six meetings during 2023. The Compensation Committee operates under a written charter adopted by the Board of Directors, which is available on our website at http://investor.sagerx.com/corporate-governance.

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Nominating and Corporate Governance Committee. The current members of the Nominating and Corporate Governance Committee are George Golumbeski, Ph.D., Steven Paul, M.D., and Geno Germano. Mr. Germano serves as the Chair of the Nominating and Corporate Governance Committee. We expect that Dr. Paul will continue to serve on the Nominating and Corporate Governance Committee until his current term ends at the Annual Meeting. Our Board of Directors has determined that each member of the Nominating and Corporate Governance Committee is “independent” as defined in the applicable Nasdaq rules.

The Nominating and Corporate Governance Committee’s responsibilities include:

The Nominating and Corporate Governance Committee held four meetings during 2023. The Nominating and Corporate Governance Committee operates under a written charter adopted by the Board of Directors, which is available on our website at http://investor.sagerx.com/corporate-governance.

Science and Technology Committee. The current members of the Science and Technology Committee are Michael F. Cola, Steven Paul, M.D., and Jeffrey M. Jonas, M.D. Dr. Jonas serves as the Chair of the Science and Technology Committee. We expect that Dr. Paul will continue to serve on the Science and Technology Committee until his current term ends at the Annual Meeting.

The Science and Technology Committee’s responsibilities include:

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The Science and Technology Committee held three meetings during 2023. The Science and Technology Committee operates under a written charter adopted by the Board of Directors, which is available on our website at http://investor.sagerx.com/corporate-governance.

Director Nomination Process

Our Board of Directors is responsible for filling vacancies on our Board of Directors and for nominating candidates for election by our stockholders each year in the class of directors whose term expires at the relevant annual meeting. The Board of Directors delegates the selection and nomination process to the Nominating and Corporate Governance Committee, with the expectation that other members of the Board of Directors and management will be requested to take part in the process, as appropriate.

Generally, the Nominating and Corporate Governance Committee identifies candidates for director nominees in consultation with management, through recommendations from members of the Board of Directors, the use of search firms or other advisors, through networking and participation in associations which aim to increase board diversity, or through such other methods as the Nominating and Corporate Governance Committee deems to be helpful to identify candidates. Once candidates have been identified, the Nominating and Corporate Governance Committee confirms that the candidates meet all of the minimum qualifications for director nominees established by the Nominating and Corporate Governance Committee. The Nominating and Corporate Governance Committee may gather information about the candidates through interviews, detailed questionnaires, comprehensive background checks or any other means that the Nominating and Corporate Governance Committee deems to be appropriate in the evaluation process. The Nominating and Corporate Governance Committee then meets as a group to discuss and evaluate the qualities and skills of each candidate, both on an individual basis and taking into account the overall composition and needs of our Board of Directors. Based on the results of the evaluation process, the Nominating and Corporate Governance Committee recommends candidates for approval by the Board of Directors to fill a vacancy or as director nominees for election to the Board of Directors by our stockholders each year in the class of directors whose term expires at the relevant annual meeting.

Qualifications, Criteria and Diversity. In considering whether to recommend any particular candidate for selection by the Board of Directors as a director nominee, the Nominating and Corporate Governance Committee will apply the following criteria that it believes must be met by all directors:

Our Board of Directors and Nominating and Corporate Governance Committee believe that it is essential that our directors represent diverse viewpoints with broad experience in areas important to the operation of the Company. When considering candidates as potential board members, the Board of Directors and the Nominating and Corporate Governance Committee evaluate the candidates’ ability to contribute to such diversity. We believe that our Board of

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Directors, taken as a whole, should provide a significant breadth of skills, experience, knowledge, and background that will allow our Board of Directors to advance our strategic objectives and fulfill our responsibilities to our stockholders. In this context, our Nominating and Corporate Governance Committee considers the following qualifications, in addition to the criteria set forth above, when evaluating nominees for our Board of Directors:

Our Nominating and Corporate Governance Committee is committed to recruitment efforts that focus on highly qualified diverse candidates, including racial, ethnic, and gender diversity. Our Nominating and Corporate Governance Committee charter requires any search firm engaged in a search for Board candidates to include qualified candidates with diversity of race, ethnicity and gender in the pool from which director candidates are chosen (also known as a “Rooney Rule” policy). We continue to network in an effort to increase diversity in our director candidate pool and ultimately on our Board of Directors. In March 2023, we appointed Jessica J. Federer to the Board of Directors, further diversifying the Board of Directors’ overall skillset and capabilities while also increasing gender diversity on the Board of Directors.

The table below summarizes certain information regarding the members of our Board of Directors, including specified categories of skills and experience based on the standards described above, certain diversity attributes and other factors important to us when evaluating our Board of Directors as a whole. The table does not summarize all of the skills, experience or diversity attributes applicable to each of our directors and the fact that a particular category of skills and experience or attribute is not listed does not mean that a director does not possess it. Moreover, the absence of a particular category of skills and experience or attribute with respect to any one director does not mean that director does not possess the ability to contribute to strategic decision-making related to that area. The type and degree of skill and experience listed below may vary among each member of our Board of Directors.

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Stockholder Recommendations. In selecting nominees for directors, the Nominating and Corporate Governance Committee will review candidates recommended by stockholders in the same manner and using the same general criteria as candidates recruited by the Nominating and Corporate Governance Committee and/or recommended by our Board of Directors and our Chief Executive Officer. Any stockholder who wishes to recommend a candidate for consideration by the Nominating and Corporate Governance Committee as a nominee for director should submit such recommendations to the Nominating and Corporate Governance Committee by sending the individual’s name and qualifications to our Secretary at Sage Therapeutics, Inc., 215 First Street, Cambridge, Massachusetts 02142, who will forward all recommendations to the Nominating and Corporate Governance Committee.

Stockholder Engagement. We believe that effective corporate governance includes active and regular engagement with our stockholders, and we are committed to investing time with our stockholders to increase transparency and gain a better understanding of the practices our stockholders most value. We communicate with our stockholders regularly and solicit input on our executive compensation, corporate governance and disclosure practices. In 2023 and early 2024, we have undertaken significant, proactive stockholder engagement and solicited feedback from our stockholders through open dialogue and individual outreach and communication. Our stockholder engagement team consists of members of our legal, human resources, and investor relations teams, and between mid-2023 and early 2024, we solicited feedback from stockholders representing approximately 87% of our outstanding shares based on public filings as of December 31, 2023, and engaged with stockholders then representing approximately 67% of our outstanding shares. The key topics discussed included executive compensation, board composition, and the option exchange program we implemented. Our discussions with our stockholders have been productive and informative and have provided a valuable opportunity to deepen our understanding of our stockholders’ interests and voting policies while sharing insight with our stockholders about our motivations and priorities with respect to governance and executive compensation.

For example, in late 2023, we engaged with several of our largest stockholders to solicit their feedback about option exchange programs, including their perspectives on certain design elements being considered at that time for an option exchange program for our employees. We then incorporated such stockholder feedback, including allowing participation only by non-executive officer employees and using exchange ratios intended to approximately result in a “value for value” or “value-neutral” exchange, into the design of our program. The option exchange program was approved by our stockholders at a special meeting of stockholders held on January 31, 2024. The option exchange program received support from ISS and Glass Lewis, and approximately 99% of stockholders that were present or represented by proxy at the special meeting of stockholders voted in favor of the program.

Stockholder Communications. The Board of Directors provides to every stockholder the ability to communicate with the Board of Directors, as a whole, and with committees of the Board of Directors or individual directors on the

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Board of Directors through an established process for stockholder communication. For a stockholder communication directed to the Board of Directors as a whole, stockholders may send such communication to the attention of the Chair of the Board via U.S. Mail or expedited delivery service to: Sage Therapeutics, Inc., 215 First Street, Cambridge, Massachusetts 02142, Attention: Chair of the Board of the Directors. All such communications will be delivered to the Board of Directors. For a stockholder communication directed to a committee of the Board of Directors or to an individual director in his or her capacity as a member of the Board of Directors, stockholders may send such communication to the attention of the individual director via U.S. Mail or expedited delivery service to: Sage Therapeutics, Inc., 215 First Street, Cambridge, Massachusetts 02142, Attention: [Name of Individual Director]. We will forward any such stockholder communication to the applicable committee chair or individual director, and the Chair of the Board in his or her capacity as a representative of the Board of Directors, to whom such stockholder communication is addressed to the address specified by each such director and the Chair of the Board, unless there are safety or security concerns that mitigate against further transmission.

Risk Oversight. Our Board of Directors administers its risk oversight function directly and indirectly through its committees. In particular, our Board of Directors performs this oversight role by using several different levels of review of risks inherent in the operation of our business and the implementation of our business strategies. In connection with its reviews of our corporate strategy and long-range plans, our Board of Directors reviews management’s assessment of the primary risks associated with those strategies and plans. In addition, our Board of Directors reviews the risks associated with our business operations and corporate functions periodically throughout the year as part of its consideration of undertaking certain activities. The Board of Directors also evaluates from time to time the processes by which our exposure to risk is assessed and managed by management.

Each of the committees of our Board of Directors also oversees risks that fall within such committee’s areas of responsibility. In performing this function, each committee has full access to management, as well as the ability to engage advisors. The following summarizes each committee’s role in the risk oversight function:

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Code of Business Conduct and Ethics. Our Values Code applies to all of our employees, consultants, officers and directors, including those officers responsible for financial reporting. The current version of our Values Code, as may be amended from time to time, is available on our website at http://investor.sagerx.com/corporate-governance. A copy of our Values Code may also be obtained, free of charge, upon a request directed to: Sage Therapeutics, Inc., 215 First Street, Cambridge, Massachusetts 02142, Attention: Legal and Compliance. We intend to disclose any amendment or waiver of a provision of our Values Code that applies to our principal executive officer, principal financial officer, or principal accounting officer, or persons performing similar functions, by posting such information on our website (available at www.sagerx.com) and/or in our public filings with the SEC.

Corporate Governance Guidelines. Our Board of Directors has adopted corporate governance guidelines to assist and guide its members in the exercise of their responsibilities. These guidelines should be interpreted in accordance with any requirements imposed by applicable federal or state laws or regulations, Nasdaq and our Certificate of Incorporation and Bylaws. Our corporate governance guidelines are available in the corporate governance section of our website at http://investor.sagerx.com/corporate-governance. Although these corporate governance guidelines have been approved by our Board of Directors, it is expected that these guidelines will evolve over time as customary practice and legal requirements change. In particular, guidelines that encompass legal, regulatory or exchange requirements as they currently exist will be deemed to be modified as and to the extent that such legal, regulatory or exchange requirements are modified. In addition, the guidelines may also be amended by our Board of Directors at any time as it deems appropriate.

Anti-Hedging Policy. Pursuant to our Insider Trading Policy, as amended and restated in 2023, no individual deemed to be covered person pursuant to our Insider Trading Policy may engage in any of the following transactions with respect to Sage securities: short sales, including short sales “against the box”; purchases or sales of puts, calls or other derivative securities; or purchases of financial instruments (including prepaid variable forward contracts, equity swaps, collars and exchange funds) or other transactions that hedge or offset, or are designed to hedge or offset, any decrease in the market value of Sage securities.

The SageCitizen Social Impact Initiative is an enterprise-wide social impact effort that activates and amplifies Sage’s long-standing commitment to:

Our development opportunities for our employees include 1:1 career coaching, a mentoring program, and expanded opportunities for professional development through in-person training and online learning. To support a culture of appreciation, we have an employee recognition program, SageAppreciation, with a digital platform to facilitate and share memorable, meaningful and personalized appreciation moments for Sage

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employees while connecting them to our mission, accomplishments and each other. Our SageFlex model enables employees to work from where they choose when the business allows, whether that be remote, in our office space, or a combination of each. Our offices are meant to be a magnet, not a mandate, where employees can gather to collaborate, connect and build relationships when they wish.

We believe that successful execution of our strategy is dependent on attracting, retaining and motivating a diverse team of highly skilled employees at all levels. We offer our employees a comprehensive total rewards package that focuses on our employees’ financial, physical and mental wellbeing. We seek to provide employees with competitive compensation, including a market-competitive salary reviewed annually, cash incentives, equity awards, matching contributions to a 401(k) retirement plan, life insurance, and the opportunity to participate in the 2014 ESPP. Our annual cash incentive bonus opportunity is tied to both company performance and individual performance to foster a pay-for-performance culture. In addition, we strive to promote our employees’ wellbeing through various activities, including wellness weeks and access to counseling through our employee assistance program. We strive to offer a highly competitive benefits package that includes medical, dental, vision and flexible spending accounts, and short-and long-term disability coverages. In 2023, we expanded our employee-centric, benefits choice approach by offering a new wellbeing reimbursement account that provides employees the opportunity to choose the benefits that best support their needs and wellbeing depending on where they are in their life journey. We regularly benchmark our rewards against our industry peers to help us remain competitive. Our voluntary turnover rate in 2023 was approximately 7.2%, compared to a median voluntary overall turnover rate of 11.6% for the life sciences, biotechnology and pharmaceutical industries reported in a 2023 Aon/Radford study.

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Our mission to pioneer solutions to deliver life-changing brain health medicines so every person can thrive depends on our ability to attract, develop, engage, and retain the industry’s highest quality talent across all dimensions of diversity. This understanding guides our approach to recruiting, managing and supporting our human capital resources. We are committed to taking action to integrate diversity, equity, inclusion, and equal opportunity to foster a diverse workforce, a sense of belonging, and innovative thinking. Accordingly, DE&I is an integrated philosophy across our core business that we take seriously. We have four core areas of focus:

Our commitment to DE&I is reflected in our employee snapshot as of year-end 2023 below:

Employee Snapshot

We are committed to fostering an inclusive environment in which everyone feels valued, respected, and empowered to contribute and provided access to the resources and opportunities to do so, while making a positive difference for patients and their families.

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PROPOSAL 2

RATIFICATION OF APPOINTMENT OF INDEPENDENT AUDITORS

On the recommendation of the Audit Committee, our Board of Directors has appointed PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2024. The Board of Directors recommends that stockholders vote “FOR” ratification of this appointment. If this proposal is not approved at the Annual Meeting, our Board of Directors will reconsider its appointment. Even if the appointment is ratified, the Audit Committee may, in its discretion, direct the appointment of a different independent registered public accounting firm at any time during the year if the Audit Committee determines that such a change would be in our stockholders’ best interests.

PricewaterhouseCoopers LLP has audited our financial statements for each fiscal year since December 31, 2013. We expect representatives of PricewaterhouseCoopers LLP to be present by webcast at the Annual Meeting and available to respond to appropriate questions. They will have the opportunity to make a statement if they desire to do so.

PricewaterhouseCoopers LLP Fees

The following table sets forth fees incurred for professional audit services and other services rendered to us by PricewaterhouseCoopers LLP and its affiliates for the fiscal years ended December 31, 2023 and December 31, 2022.

Audit Fees. Audit fees consist of fees billed for professional services performed by PricewaterhouseCoopers LLP for the audit of our annual consolidated financial statements, the review of interim condensed consolidated financial statements, and related services that are normally provided in connection with registration statements, including the registration statements for our follow-on offerings.

Audit-Related Fees. Audit-related fees consist of fees billed by PricewaterhouseCoopers LLP for assurance and related services that are reasonably related to the performance of the audit or review of our consolidated financial statements. In 2023 and 2022, the audit-related fees were incurred for accounting consultations related to the future accounting treatment of the collaboration with Biogen MA Inc., or BIMA, and Biogen International GmbH, or Biogen International. We collectively refer to BIMA and Biogen International as Biogen.

Tax Fees. Tax fees consist of fees for tax-related services, including tax consulting and compliance performed by PricewaterhouseCoopers LLP.

All Other Fees. All other fees in 2023 and 2022 consisted of fees for software programs, including a proprietary accounting research database.

Pre-Approval of Audit and Non-Audit Services

It is the policy of our Audit Committee that all services to be provided by our independent registered public accounting firm, including audit services and permitted audit-related and non-audit services, must be approved in advance by our Audit Committee or through properly delegated authority to one or more members of the Audit Committee.

All PricewaterhouseCoopers LLP services and fees in the fiscal years ended December 31, 2023 and 2022 were pre-approved by the Audit Committee or through properly delegated authority.

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Vote Required and Board of Directors’ Recommendation

The approval of Proposal 2 requires that a majority of the votes properly cast be voted FOR this proposal. Shares that are voted “abstain” and broker non-votes will not affect the outcome of this proposal.

Our Board of Directors recommends that stockholders vote “FOR” ratification of the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2024.

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PROPOSAL 3

ADVISORY VOTE ON NAMED EXECUTIVE OFFICER COMPENSATION

Our Board of Directors is committed to excellence in governance. As part of this commitment, and as required by Section 14A(a)(1) of the Exchange Act, our Board of Directors is providing our stockholders with an opportunity to cast a non-binding, advisory vote to approve the compensation of our named executive officers.

As described below under “Executive Officer and Director Compensation—Compensation Discussion and Analysis,” we have developed a compensation program that is designed to attract and retain key executives responsible for our success and motivate management to enhance long-term stockholder value. The executive compensation program is designed to reward short-term and long-term performance and to align the financial interests of executive officers with the interests of our stockholders. We believe our executive compensation program strikes an appropriate balance between the implementation of responsible, measured compensation practices and the effective provision of incentives for our named executive officers to exert their best efforts for our success.

We are asking for stockholder approval, on an advisory basis, of the compensation of our named executive officers as disclosed in this Proxy Statement, which includes the disclosures in the “Executive Officer and Director Compensation—Compensation Discussion and Analysis” section below, and the compensation tables and the narrative discussion following the compensation tables in this Proxy Statement. This vote is not intended to address any specific item of compensation, but rather the overall compensation of our named executive officers and the policies and practices described in this Proxy Statement. For the reasons discussed above, our Board of Directors unanimously recommends that our stockholders vote in favor of the following resolution:

“RESOLVED, that the Company’s stockholders hereby approve, on an advisory basis, the compensation of the named executive officers, as disclosed in the Company’s proxy statement for the 2024 Annual Meeting of Stockholders pursuant to the compensation disclosure rules of the Securities and Exchange Commission, including the Compensation Discussion and Analysis, Summary Compensation Table and the other compensation related tables and disclosure.”

As this vote is advisory, it will not be binding upon our Board of Directors or the Compensation Committee and neither our Board of Directors nor our Compensation Committee will be required to take any action as a result of the outcome of this vote. However, our Compensation Committee will carefully consider the outcome of this vote when considering future executive compensation policies and decisions.

Vote Required and Board of Directors’ Recommendation

The approval of Proposal 3 requires that a majority of the votes properly cast be voted FOR this proposal. Shares that are voted “abstain” and broker non-votes will not affect the outcome of this proposal.

Our Board of Directors recommends that stockholders vote “FOR” the advisory resolution approving our named executive officer compensation.

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PROPOSAL 4

APPROVAL OF THE SAGE THERAPEUTICS, INC. 2024 EQUITY INCENTIVE PLAN

Why We are Requesting Stockholder Approval

We are asking stockholders to approve the Sage Therapeutics, Inc. 2024 Equity Incentive Plan, or the 2024 Plan. Our Board of Directors believes that our success depends, in large part, on our ability to maintain a competitive position by attracting, retaining and motivating the best talent in what is a competitive labor market. Central to these objectives is our equity-based compensation program, which is consistent with our compensation philosophy and the compensatory practices of other companies in our peer group and other companies that we compete with for talent. We and our Board of Directors understand that our equity compensation needs must be balanced against the dilutive effect of such programs on our stockholders. Based on careful weighing of these considerations, as more fully described below, on April 4, 2024, or the Board Approval Date, following the recommendation of the Compensation Committee, the Board of Directors adopted the 2024 Plan, subject to stockholder approval.

The 2024 Plan is intended to replace the Sage Therapeutics, Inc. 2014 Stock Option and Incentive Plan, or the 2014 Plan, which will expire by its terms on July 23, 2024. If our stockholders approve the 2024 Plan, we will not grant any further awards under the 2014 Plan after the time of such approval, but awards previously granted under the 2014 Plan will remain outstanding. If the stockholders do not approve the 2024 Plan, then the 2014 Plan will remain in effect pursuant to its existing terms until its expiration, and we will consider other alternatives as a means of properly and competitively compensating our employees, directors and other service providers.

We intend to utilize the 2024 Plan as we have utilized the 2014 Plan: specifically, to grant equity awards to our employees, non-employee directors, consultants, and advisors in order to recruit, incentivize, retain and reward them.

Our Compensation Committee determined the requested number of shares for the 2024 Plan based on projected annual equity awards to our employees and non-employee directors, new-hire equity awards, employee recognition and promotion awards, and an assessment of the magnitude of the share reserve under the 2024 Plan that our stockholders would likely find acceptable. In addition, our Compensation Committee considered the impact of our recent option exchange program, which was approved by our stockholders at a special meeting held on January 31, 2024, and which was completed on February 21, 2024, or collectively the Option Exchange Program. We designed the Option Exchange Program with the goals of restoring equity value for our non-executive officer employees, increasing employee retention and motivation in a competitive labor market, and better aligning our employee and stockholder interests for long-term growth. Pursuant to the Option Exchange Program, our non-executive officer employees were given the opportunity, pursuant to the tender offer rules of the SEC, to exchange certain outstanding options with an exercise price of $35.00 per share or higher, for a lesser number of replacement options with an exercise price equal to the closing price of our common stock on the date of grant. The replacement options were granted with a new vesting schedule and seven-year term. We cancelled tendered options to purchase 3,079,608 shares of common stock and we issued replacement options to purchase 1,483,113 shares of common stock. The net shares subject to cancelled options tendered by participants in the Option Exchange Program were not returned to the pool of shares available for future grants under the 2014 Plan to prevent the Option Exchange Program from being dilutive to our stockholders. Further, our executive officers and directors were not eligible to participate in the Option Exchange Program, and such individuals continue to have a significant portion of their equity holdings in the Company in underwater stock options. As a result, while we view the completion of Option Exchange Program as an important step in helping our equity compensation program serve its intended purposes of motivating employees and aligning employee interests with those of our stockholders, stockholder approval of the 2024 Plan is requested in order for us to have the ability to bring the equity holdings of our employees, including our executive officers, and our directors closer to a market-competitive position and to support our continued business objectives and the future growth of our Company.

If stockholders approve the 2024 Plan, subject to adjustment in the event of stock splits and other similar events, awards may be made under the 2024 Plan for up to a number of shares of common stock equal to the sum of: (i) 5,500,000 shares of common stock and (ii) such additional number of shares of common stock as is equal to the number of shares of common stock subject to awards granted under the 2014 Plan that are outstanding as of the date that the 2024 Plan is approved by our stockholders and which awards expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase

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right (subject, however, in the case of incentive stock options, to any limitations under the Internal Revenue Code of 1986, as amended, and any regulations thereunder, or collectively the Code. The 2024 Plan does not include an evergreen provision (which the 2014 Plan contains) and includes several features that are consistent with protecting the interests of our stockholders and sound corporate governance practices, as described below.

In addition to grants made to newly hired employees under the 2014 Plan, in the past, we periodically relied on the inducement grant exception under Nasdaq Listing Rule 5635(c)(4) to grant nonstatutory stock options, or Inducement Awards, under our 2016 Inducement Equity Plan, as amended and restated, or the 2016 Inducement Plan, to newly hired employees who were eligible under the Nasdaq rules to receive such grants. However, since 2020, we have not granted any Inducement Awards under the 2016 Inducement Plan and have instead made grants to newly hired employees only under the 2014 Plan. As a result, and in connection with considering the approval of the 2024 Plan, effective as of April 16, 2024, our Board of Directors adopted an amendment to the 2016 Inducement Plan, or the Inducement Plan Amendment, to reduce the number of shares available for grant thereunder by 2,482,526 shares, such that no future awards may be granted under the 2016 Inducement Plan following the date of the Inducement Plan Amendment, but awards previously granted under the 2016 Inducement Plan will remain outstanding. The number of shares available under the 2024 Plan, if the plan is approved, was carefully calibrated to enable us to make new-hire equity grants as well as annual and ongoing equity grants to our current employees under the 2024 Plan.

The following table includes information, as of April 16, 2024, regarding all of our outstanding equity awards under all of our equity-based compensation plans and arrangements under which shares of common stock may be issued, inclusive of any impacts of the Option Exchange Program, as well as the maximum number of shares we will grant between April 16, 2024 and the date of the Annual Meeting. Specifically, the table includes (i) shares subject to outstanding awards under the 2014 Plan, the 2011 Stock Option and Grant Plan, or the 2011 Plan, and the 2016 Inducement Plan and (ii) 75,000 shares, which represents the maximum number of shares we will grant pursuant to promotion and new hire awards under the 2014 Plan between April 16, 2024 and the date of the Annual Meeting, but does not include (iii) shares issuable under our 2014 Employee Stock Purchase Plan, as amended or (iv) 3,489,240 shares that will remain available under the 2014 Plan for future awards as of the date of the Annual Meeting (as we will not grant awards with respect to such shares between April 16, 2024 and the date of the Annual Meeting and such shares will no longer remain available for future awards under the 2014 Plan or the 2024 Plan upon stockholder approval of the 2024 Plan).

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As of April 16, 2024, there were no outstanding shares of restricted stock, no stock appreciation rights, or SARs, or any other stock-based awards.

We expect that the proposed share pool under the 2024 Plan will allow us to continue to grant equity awards at our historic rates for approximately two to three years, but the actual duration of the share pool may vary based on changes in participation, the Company’s stock price and market practice.

We believe that our stock-based compensation programs have been integral to our success in the past and will be important to our ability to succeed in the future. The 2014 Plan will expire on July 23, 2024, in accordance with its terms. Additionally, as a result of the Inducement Plan Amendment, no future awards may be granted under the 2016 Inducement Plan. If the 2024 Plan is not approved by our stockholders, we will not be able to make equity incentive awards under the 2014 Plan after the expiration of the 2014 Plan to meet our hiring and retention needs in a highly competitive market, which could have an adverse impact on our business. Further, if the 2024 Plan is not approved, we could be forced to increase cash compensation, which will reduce the resources we are able to allocate towards meeting our business needs and objectives. Therefore, we believe the approval of the 2024 Plan is vital to our future success.

If this proposal is approved by our stockholders, we intend to register the additional shares reserved for issuance under the 2024 Plan by filing a Registration Statement on Form S-8 as soon as practicable following such approval.

Our Board of Directors believes approval of the 2024 Plan is in the best interests of Sage and its stockholders and recommends a vote “FOR” the approval of the 2024 Plan.

Following below is a discussion of:

Highlights of the 2024 Plan

The 2024 Plan includes several features that are consistent with protecting the interests of our stockholders and sound corporate governance practices. These features are highlighted below and are more fully described in the summary of the 2024 Plan further below in this proposal as well as in the copy of the 2024 Plan in Appendix A to this proxy statement.

No Evergreen. The 2024 Plan does not include an “evergreen” or other provision that automatically increases the number of shares available for grant under the plan and therefore any increase to the maximum share reserve in the 2024 Plan is subject to approval by our stockholders, allowing our stockholders to have a say in our equity compensation programs.

Clawback Policy. In accepting an Award under the 2024 Plan, a participant agrees to be bound by any clawback policy that the Company has in effect or may adopt in the future (including our clawback policy adopted in 2023 in compliance with applicable Nasdaq rules).

Minimum Vesting Provisions. Minimum vesting provisions of one year generally apply to all awards to participants, with the exception of awards for up to 5% of the shares of stock reserved under the 2024 Plan.

No Automatic Vesting of Awards on a Change in Control Event. The 2024 Plan does not provide for the automatic vesting of awards in connection with a change in control event.

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No Liberal Share Recycling. The 2024 Plan prohibits the re-granting of (i) shares withheld or delivered to satisfy the exercise price of an award or to satisfy tax withholding obligations, (ii) shares that were subject to a SAR and were not issued upon the net settlement or net exercise of such award, or (iii) shares repurchased on the open market using proceeds from the exercise of an award.

No Repricing of Awards. The 2024 Plan prohibits the direct or indirect repricing of stock options or SARs without stockholder approval.

No Discounted Stock Options or SARs. All stock options and SARs must have an exercise or measurement price that is at least equal to the fair market value of the underlying common stock on the date of grant.

No Reload Stock Options or SARs. No stock options or SARs granted under the 2024 Plan may contain a provision entitling the award holder to the automatic grant of additional stock options or SARs in connection with any exercise of the original stock option or SAR.

No Dividend Equivalents on Stock Options or SARs. No stock options or SARs granted under the 2024 Plan may provide for the payment or accrual of dividend equivalents.

Dividends and Dividend Equivalents on Restricted Stock, Restricted Stock Units and Other-Stock Based Awards Not Paid Until Award Vests. Any dividends or dividend equivalents paid or credited with respect to restricted stock, restricted stock units, or RSUs, or other stock-based awards will be subject to the same restrictions on transfer and forfeitability as the award with respect to which they are paid.

Limit on Non-Employee Director Compensation. The maximum aggregate amount of cash earned or paid and value of awards (calculated based on grant date fair value for financial reporting purposes) granted to any non-employee director in any calendar year may not exceed $750,000 in the case of an incumbent director. Such maximum aggregate amount shall not exceed $1,500,000 in any calendar year for any individual non-employee director in such non-employee director’s initial year of election or appointment. Exceptions to these limitations may only be made by our Board of Directors in extraordinary circumstances, provided that the non-employee director receiving any additional compensation may not participate in the decision to award such compensation.

Material Amendments Require Stockholder Approval. Stockholder approval is required prior to an amendment of the 2024 Plan that would (i) materially increase the number of shares authorized (other than as provided under the 2024 Plan with respect to certain corporate events or substitute awards), (ii) expand the types of awards that may be granted, or (iii) materially expand the class of participants eligible to participate.

Administered by an Independent Committee. The 2024 Plan is administered by the Compensation Committee, as delegated by our Board of Directors. The Compensation Committee is made up entirely of independent directors.

Reasons Why Stockholders Should Approve the 2024 Plan

Incentivizes, Retains and Motivates Talent. It is critical to our success that we incentivize, retain and motivate the best talent in what is a competitive labor market. Our equity-based compensation program has always been and will continue to be a key component in our ability to pay market-competitive compensation to our employees.

Aligns with Our Pay-for-Performance Compensation Philosophy. We believe that equity-based compensation is inherently performance-based. As the value of our stock appreciates, our employees receive greater compensation at the same time that our stockholders are receiving a greater return on their investment. Conversely, if the stock price does not appreciate following the grant of an equity award, then our employees would not receive any compensation in respect of stock options and would receive lower compensation than intended in respect of restricted stock units.

Aligns Employee and Director Interests with Stockholder Interests. Providing our employees and non-employee directors with compensation in the form of equity directly aligns the interests of those employees and non-employee directors with the interests of our stockholders. If the 2024 Plan is approved by our stockholders, we will be able to continue granting equity-based incentives that foster this alignment between our employees and non-employee directors and our stockholders.

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Consistent with Stockholder Interests and Sound Corporate Governance. As described under the heading “Highlights of the 2024 Plan” and more thoroughly below, the 2024 Plan was purposefully designed to include features that are consistent with the interests of our stockholders and sound corporate governance practices.

Information Regarding Overhang and Gross Burn Rate

In developing our share request for the 2024 Plan and analyzing the impact on our stockholders of utilizing equity as a means of compensation, we considered both our “overhang” and our “gross burn rate.”

Overhang

Overhang is a measure of potential dilution, which we define as the sum of (i) the total number of shares underlying all equity awards outstanding and (ii) the total number of shares available for future award grants, divided by the number of shares of common stock outstanding. In the paragraphs below we have calculated our overhang as of April 16, 2024 both prior to and following the impact of the adoption of the 2024 Plan, assuming stockholder approval of the 2024 Plan. We refer to our overhang, as determined prior to the impact of the adoption of the 2024 Plan, as our “actual overhang”, and as determined following such impact, as our “pro forma overhang”. For purposes of these calculations we (i) included the impacts of the Option Exchange Program and (ii) calculated the number of equity awards outstanding as of such date based on the “target” number of shares subject to equity awards with TSR milestones and the “maximum” number of shares subject to equity awards with all other performance-based achievement milestones.

Actual Overhang. As of April 16, 2024, there were 11,167,204 shares underlying all equity awards outstanding), 3,564,240 shares available under the 2014 Plan for future awards, and 60,182,031 shares of common stock outstanding. Accordingly, our actual overhang as of April 16, 2024 was 24.5%.

Pro Forma Overhang. If, for purposes of the overhang calculation, we include (i) the 5,500,000 shares proposed to be authorized for grant under the 2024 Plan and (ii) 75,000 shares, which represents the maximum number of shares we will grant pursuant to promotion and new hire awards under the 2014 Plan between April 16, 2024 and the date of the Annual Meeting, and we exclude (iii) 3,489,240 shares that will remain available for issuance under the 2014 Plan for future awards as of the date of the Annual Meeting (as we will not grant awards with respect to such shares between April 16, 2024 and the date of the Annual Meeting and such shares will no longer remain available for future awards under the 2014 Plan or the 2024 Plan upon stockholder approval of the 2024 Plan), and (iv) 2,462,326 shares that are no longer available for issuance under the 2016 Inducement Plan following the adoption of the Inducement Plan Amendment, our pro forma overhang on April 16, 2024 would have been 27.8%.

Gross Burn Rate

Gross burn rate provides a measure of the potential dilutive impact of our equity award program, which we calculate by dividing the number of shares subject to equity awards granted during the year by the basic weighted average number of shares outstanding. Set forth below is a table that reflects our gross burn rate for the 2023, 2022 and 2021 calendar years, as well as an average over those years.

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Equity Compensation Plan Information

For more information on our equity compensation plans, please see the section titled “Executive Officer and Director Compensation—Equity Compensation Plan Information as of December 31, 2023” contained elsewhere in this proxy statement.

Description of the 2024 Plan

The following is a brief summary of the 2024 Plan, a copy of which is attached as Appendix A to this proxy statement. References to the Board of Directors in this summary shall include the Compensation Committee or any similar committee or sub-committee or the Delegated Persons (as defined below) to the extent that our Board of Directors’ powers or authority under the 2024 Plan have been delegated to such committee or Delegated Persons, in accordance with the 2024 Plan.

For purposes of this proposal and except where the context otherwise requires, the term “Company” and similar terms shall include any of the Company’s present or future parent or subsidiary corporations as defined in Sections 424(e) or (f) of the Code and any other business venture (including, without limitation, joint venture or limited liability company) in which the Company has a controlling interest, as determined by the Board of Directors.

Types of Awards; Shares Available for Awards; Share Counting Rules

The 2024 Plan provides for the grant of incentive stock options intended to qualify under Section 422 of the Code, nonstatutory stock options, SARs, restricted stock, RSUs, other stock-based awards, and cash awards as described below, which we refer to, collectively, as awards.

Subject to adjustment in the event of stock splits, stock dividends and other similar events, awards may be made under the 2024 Plan for up to a number of shares of common stock equal to the sum of: (i) 5,500,000 shares of our common stock; and (ii) such additional number of shares of common stock as is equal to the number of shares of common stock subject to awards granted under the 2014 Plan that are outstanding as of the date the 2024 Plan is approved by our stockholders which awards expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right (subject, however, in the case of incentive stock options to any limitations under the Code). Awards with respect to no more than 16,323,734 shares of our common stock may be granted under the 2024 Plan in the form of incentive stock options. Shares of common stock issued under the 2024 Plan may consist in whole or in part of authorized but unissued shares or treasury shares.

The 2024 Plan provides that the maximum aggregate amount of cash and value of awards (calculated based on grant date fair value for financial reporting purposes) granted to any individual non-employee director in any calendar year may not exceed $750,000 in the case of an incumbent director. Such maximum aggregate amount shall not exceed $1,500,000 in any calendar year for any individual non-employee director in such non-employee director’s initial year of election or appointment. Fees paid by the Company on behalf of any non-employee director in connection with regulatory compliance and any amounts paid to a non-employee director as reimbursement of an expense will not count against these limits. Exceptions to these limitations may only be made by our Board of Directors in extraordinary circumstances, provided that any non-employee director receiving additional compensation may not participate in the decision to award such compensation. This limitation does not apply to cash or awards granted to a non-employee director in his or her capacity as an advisor or consultant to the Company. The Board of Directors may from time to time adopt policies, practices or guidelines to implement the terms of the 2024 Plan as it relates to non-employee director compensation, subject in all cases to the policies, limits and terms and conditions set forth in the 2024 Plan.

For purposes of counting the number of shares available for the grant of awards under the 2024 Plan, all shares of common stock covered by SARs shall be counted against the number of shares available for the grant of awards under the 2024 Plan. However, SARs that may be settled only in cash will not be so counted. Similarly, to the extent that an

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RSU award may be settled only in cash, no shares will be counted against the shares available for the grant of awards under the 2024 Plan. In addition, if we grant a SAR in tandem with a stock option for the same number of shares of our common stock and provide that only one such award may be exercised, referred to as a tandem SAR, only the shares covered by the stock option, and not the shares covered by the tandem SAR, will be so counted, and the expiration of one in connection with the other’s exercise will not restore shares to the 2024 Plan.

Shares covered by awards under the 2024 Plan that expire or are terminated, surrendered, or cancelled without having been fully exercised or are forfeited in whole or in part (including as the result of shares subject to such award being repurchased by us at the original issuance price pursuant to a contractual repurchase right) or that result in any shares not being issued (including as a result of an award being settled in cash rather than stock) will again be available for the grant of awards under the 2024 Plan (subject, in the case of incentive stock options, to any limitations under the Code). In the case of the exercise of a SAR, the number of shares counted against the shares available for the grant of awards under the 2024 Plan will be the full number of shares subject to the SAR multiplied by the percentage of the SAR actually exercised, regardless of the number of shares actually used to settle the SAR upon exercise, and the shares covered by a tandem SAR will not again become available for grant upon the expiration or termination of the tandem SAR.

Shares of common stock that are delivered (by actual delivery, attestation, or net exercise) to us by a participant to purchase shares of common stock upon exercise of an award or to satisfy tax withholding obligations (including shares retained from the award creating the tax obligation) will not be added back to the number of shares available for the future grant of awards under the 2024 Plan. Shares repurchased by us on the open market using proceeds from the exercise of an award will not increase the number of shares available for future grant of awards under the 2024 Plan.

In connection with a merger or consolidation of an entity with us or our acquisition of property or stock of an entity, our Board of Directors may grant awards under the 2024 Plan in substitution for any stock options or other stock or stock-based awards granted by such entity or an affiliate thereof on such terms as our Board of Directors determines appropriate in the circumstances, notwithstanding any limitation on awards contained in the 2024 Plan. No such substitute awards shall count against the overall share limit contained in the 2024 Plan, except as required by reason of Section 422 and related provisions of the Code.

Descriptions of Awards

Stock Options. A participant who is awarded a stock option receives the right to purchase a specified number of shares of common stock at a specified exercise price and subject to the other terms and conditions that are specified in connection with the award agreement. A stock option that is not intended to be an “incentive stock option” is a “nonstatutory stock option.” Stock options may not be granted with an exercise price that is less than 100% of the fair market value of our common stock on the date of grant. If our Board of Directors approves the grant of a stock option with an exercise price to be determined on a future date, the exercise price may not be less than 100% of the fair market value of our common stock on that future date. Under present law, incentive stock options may not be granted at an exercise price less than 110% of the fair market value in the case of stock options granted to participants who hold more than 10% of the total combined voting power of all classes of our stock or any of our subsidiaries. Under the terms of the 2024 Plan, stock options may not be granted for a term in excess of ten years (and, under present law, five years in the case of incentive stock options granted to participants who hold greater than 10% of the total combined voting power of all classes of our stock or any of our subsidiaries).

The 2024 Plan permits participants to pay the exercise price of stock options using one or more of the following manners of payment: (i) payment by cash or by check, (ii) except as may otherwise be provided in the applicable award agreement or approved by our Board of Directors, in connection with a “cashless exercise” through a broker, (iii) to the extent provided in the applicable award agreement or approved by our Board of Directors, and subject to certain conditions, by delivery to us (either by actual delivery or attestation) of shares of common stock owned by the participant valued at their fair market value, (iv) to the extent provided in an applicable nonstatutory stock option award agreement or approved by our Board of Directors, by delivery of a notice of “net exercise” as a result of which we will retain a number of shares of common stock otherwise issuable pursuant to the stock option equal to the aggregate exercise price for the portion of the stock option being exercised divided by the fair market value of our common stock on the date of exercise, (v) to the extent permitted by applicable law and provided for in the applicable award

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agreement or approved by our Board of Directors, by any other lawful means, or (vi) by any combination of these forms of payment. No stock option granted under the 2024 Plan may contain a provision entitling the participant to the automatic grant of additional stock options in connection with any exercise of the original stock option. No stock options granted under the 2024 Plan may provide for the payment or accrual of dividend equivalents.

Stock Appreciation Rights. A participant who is awarded a SAR receives, upon exercise, a number of shares of our common stock, or cash (or a combination of shares of our common stock and cash) determined by reference to appreciation, from and after the date of grant, in the fair market value of a share of our common stock over the measurement price. The 2024 Plan provides that the measurement price of a SAR may not be less than 100% of the fair market value of our common stock on the date the SAR is granted (provided, however, that if our Board of Directors approves the grant of a SAR effective as of a future date, the measurement price shall not be less than 100% of the fair market value on such future date) and that SARs may not be granted with a term in excess of 10 years. No SARs granted under the 2024 Plan may contain a provision entitling the participant to the automatic grant of additional SARs in connection with any exercise of the original SAR. No SARs granted under the 2024 Plan may provide for the payment or accrual of dividend equivalents.

Limitation on Repricing of Stock Options or SARs. Unless such action is approved by our stockholders or otherwise permitted under the terms of the 2024 Plan in connection with certain changes in capitalization and reorganization events, we may not (i) amend any outstanding stock option or SAR granted under the 2024 Plan to provide an exercise price or measurement price per share that is lower than the then-current exercise price or measurement price per share of such outstanding stock option or SAR, (ii) cancel any outstanding stock option or SAR (whether or not granted under the 2024 Plan) and grant in substitution therefor new awards under the 2024 Plan (other than certain substitute awards issued in connection with a merger or consolidation of an entity with us or an acquisition by us, described above) covering the same or a different number of shares of our common stock and having an exercise price or measurement price per share lower than the then-current exercise price or measurement price per share of the cancelled stock option or SAR, (iii) cancel in exchange for a cash payment any outstanding stock option or SAR with an exercise price or measurement price per share above the then-current fair market value of our common stock, or (iv) take any other action under the 2024 Plan that constitutes a “repricing” within the meaning of the rules of the Nasdaq Stock Market or any other exchange or marketplace on which the Company’s stock is listed or traded.

Restricted Stock Awards. A participant who is granted a restricted stock award is entitled to acquire shares of our common stock, subject to our right to repurchase all or part of such shares at their issue price or other stated or formula price (or to require forfeiture of such shares if issued at no cost), in the event that the conditions specified in the applicable award are not satisfied prior to the end of the applicable restriction period established for such award. Any dividends (whether paid in cash, stock or property) declared and paid by us with respect to shares of restricted stock will be paid to the participant only if and when such shares become free from the restrictions on transferability and forfeitability that apply to such shares. No interest will be paid on unvested dividends.

Restricted Stock Unit Awards. A participant who is granted an RSU award is entitled to receive shares of our common stock, or cash equal to the fair market value of such shares or a combination thereof, in the event that the conditions specified in the applicable award are satisfied, with such shares to be delivered at the time such award vests or on a deferred basis pursuant to the terms and conditions established by our Board of Directors. Our Board of Directors may provide that settlement of RSUs will be deferred, on a mandatory basis or at the election of the participant, in a manner that complies with Section 409A of the Code. A participant has no voting rights with respect to any RSU. An RSU award agreement may provide the applicable participant with the right to receive an amount equal to any dividends or other distributions declared and paid on an equal number of outstanding shares of our common stock. Any such dividend equivalents may be credited to an account for the participant, settled in cash and/or shares of our common stock and will be subject to the same restrictions on transfer and forfeitability as the RSUs with respect to which such dividend equivalents are awarded. No interest will be paid on dividend equivalents.

Other Stock-Based Awards. Under the 2024 Plan, our Board of Directors may grant other awards of shares of our common stock, and other awards that are valued in whole or in part by reference to, or are otherwise based on, shares of our common stock or other property, having such terms and conditions as our Board of Directors may determine. We refer to these types of awards as other stock-based awards. At the discretion of our Board of Directors, other stock-based awards may be used as a form of payment in settlement of other awards granted under the 2024 Plan or as payment in lieu of compensation to which a participant is otherwise entitled. Other stock-based awards may be paid in

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shares of our common stock or in cash, as our Board of Directors may determine. The award agreement of an other stock-based award may provide the participant who receives such award with the right to receive dividend equivalents. Dividend equivalents may be credited to an account for the participant, settled in cash and/or shares of our common stock and will be subject to the same restrictions on transfer and forfeitability as the other stock-based award with respect to which they are awarded. No interest will be paid on dividend equivalents.

Cash Awards. Under the 2024 Plan, the Board of Directors has the right to grant cash-based awards including awards subject to performance conditions.

Performance Conditions. Awards under the 2024 Plan may be made subject to the achievement of performance goals. Our Board of Directors may specify that the degree of granting, vesting, and/or payout of any award subject to performance-based vesting conditions will be subject to the achievement of one or more of the following performance measures established by the Board of Directors, which may be based on the relative or absolute attainment of specified levels of one or any combination of the following measures (and which may be determined pursuant to generally accepted accounting principles, or GAAP, or on a non-GAAP basis, as determined by the Board of Directors): (i) achievement of domestic or international regulatory milestones, including the submission of filings required to advance products, services or technologies in clinical development or the achievement of approvals by regulatory authorities relating to the commercialization of products, services or technologies; (ii) specified levels of product sales, patients on therapy, net income, earnings before or after discontinued operations, interest, taxes, depreciation and/or amortization, operating profit before or after discontinued operations and/or taxes, sales, sales growth, earnings growth, cash flow or cash position, gross margins, stock price, market share, return on sales, assets, equity or investment; (iii) the entry into or completion of a phase of clinical development for any product, service or technology, such as the entry into or completion of phase 1, 2 and/or 3 clinical trials; (iv) the achievement of discovery, preclinical and clinical stage scientific objectives, discoveries or inventions or results for products, services or technologies under research and development; (v) the entry into an arrangement or agreement with a third party for the development, commercialization, marketing or distribution of products, services or technologies, or for conducting a research program to discover and develop a product, service or technology, and/or the achievement of milestones under such arrangement or agreement, including events that trigger an obligation or payment right; (vi) the consummation of debt or equity financing transactions, or acquisitions of business, technologies or assets; (vii) new product or service releases; (viii) the achievement of qualitative or quantitative performance measures set forth in operating plans approved by the Board of Directors from time to time; (ix) improvement of financial ratings; (x) achievement of balance sheet or income statement objectives; (xi) total stockholder return; (xii) other comparable measures of financial and operational performance; and/or (xiii) any other measure selected by the Board of Directors. Such goals may reflect absolute entity or business unit performance or a relative comparison to the performance of a peer group of entities or other external measure of the selected performance criteria and may be absolute in their terms or measured against or in relationship to other companies comparably, similarly or otherwise situated. The Board of Directors may specify that such performance measures will be adjusted to exclude any one or more of: (a) extraordinary items; (b) gains or losses on the dispositions of discontinued operations; (c) the cumulative effects of changes in accounting principles; (d) the write-down of any asset; (e) fluctuation in foreign currency exchange rates; (f) charges for restructuring and rationalization programs; (g) non-cash, mark-to-market adjustments on derivative instruments; (h) amortization of purchased intangibles; (i) the net impact of tax rate changes; (j) non-cash asset impairment charges; and (k) any other factors as the Board of Directors may determine. Such performance measures may: (A) vary by participant and may be different for different awards; (B) be particular to a participant or the department, branch, line of business, subsidiary or other unit in which the participant works and (C) cover such period as may be specified by the Board of Directors. The Board of Directors will have the authority to make equitable adjustments to the performance goals, including in recognition of any changes in the Company’s capitalization, unusual or non-recurring events affecting the Company or the financial statements of the Company, in response to changes in applicable laws or regulations or to account for items of gain, loss or expense determined to be extraordinary or unusual in nature or infrequent in occurrence or related to the disposal of a segment of a business or related to a change in accounting principles. Our Board of Directors may adjust the amount of cash or number of shares payable pursuant to a performance award, and our Board of Directors may, at any time, waive the achievement of the applicable performance measures.

Notwithstanding its designation as a performance award, no stock option or SAR will provide for the payment or accrual of dividend equivalents, any dividends declared and paid by the Company with respect to shares of restricted stock will be subject to the same dividend rules for restricted stock awards not designated as a performance award and

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any right to receive dividend equivalents on an award of RSUs and other stock-based awards will be subject to the same dividend equivalent rules for such awards that are not designated as a performance award.

Eligibility to Receive Awards

All of our employees, officers, and directors, as well as our consultants and advisors, are eligible to receive awards under the 2024 Plan. However, incentive stock options may only be granted to our employees, employees of our present or future parent or subsidiary corporations as defined in Sections 424(e) or (f) of the Code, and employees of any other entities the employees of which are eligible to receive incentive stock options under the Code.

As of April 16, 2024, approximately 629 persons were eligible to receive awards under the 2024 Plan, including 5 executive officers (who are current employees), 483 employees (excluding executive officers), 8 non-employee directors, 98 consultants and 35 advisors (excluding consultants).

On April 19, 2024, the last reported sale price of our common stock on the Nasdaq Global Market was $13.33.

Transferability of Awards

Awards shall not be sold, assigned, transferred, pledged or otherwise encumbered by a participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution or, other than in the case of an incentive stock option, pursuant to a qualified domestic relations order. During the life of the participant, awards are exercisable only by the participant. However, except with respect to awards that are subject to Section 409A of the Code and incentive stock options, our Board of Directors may permit or provide in an award for the gratuitous transfer of the award by the participant to or for the benefit of any immediate family member, family trust or other entity established for the benefit of the participant and/or an immediate family member thereof if we would be eligible to use a Form S-8 under the Securities Act of 1933, as amended, for the registration of the sale of the common stock subject to such award to the proposed transferee. Further, we are not required to recognize any such permitted transfer until such time as the permitted transferee has, as a condition to the transfer, delivered to us a written instrument in form and substance satisfactory to us confirming that such transferee will be bound by all of the terms and conditions of the award. None of the restrictions described in this paragraph prohibit a transfer from the participant to the Company.

No Rights as a Stockholder

No participant or designated beneficiary shall have any rights as a stockholder with respect to any shares of common stock to be distributed with respect to an award granted under the 2024 Plan until becoming a record holder of such shares, subject to the terms of an award agreement.

Clawback

In accepting an award under the 2024 Plan, a participant agrees to be bound by any clawback policy that the Company has in effect or may adopt in the future, including without limitation the Sage Therapeutics, Inc. Compensation Recovery Policy adopted in accordance with stock exchange listing requirements (or any successor policy). A participant agrees that in the event it is determined in accordance with any such policy that any award (including any dividends, unvested dividends or dividend equivalents paid with respect thereto), any shares of common stock issued upon exercise or settlement thereof (including securities or other property received therefor), or any other proceeds from the exercise or settlement of such award or the sale of such shares of common stock or any other compensation subject to such policy must be forfeited or reimbursed to the Company, the participant will promptly take any action necessary to effectuate such forfeiture and/or reimbursement as determined by the Company.

New Plan Benefits Table

Set forth below is the “new plan benefits table”, which reflects the dollar value and number of awards to be granted under the 2024 Plan in the future, to the extent we are able to determine such figures at this time. The granting of awards under the 2024 Plan is discretionary, and we cannot now determine the number or type of awards to be granted in the future to any particular person or group, except that under our non-employee director compensation policy, we

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are obligated to grant, on an annual basis, each of our non-employee directors a stock option to purchase shares of our common stock. If the 2024 Plan is approved by our stockholders, subject to the limitations described in our current non-employee director compensation policy, each non-employee director is expected to receive an annual stock option award of 12,500 shares under the 2024 Plan on the date of our Annual Meeting, for an aggregate of 87,500 shares of our common stock subject to such stock options. See “Director Compensation” for a further discussion of non-employee director compensation.

If our stockholders do not approve the 2024 Plan, we will grant the equity awards to be made on the date of the Annual Meeting to the non-employee directors who are then-serving as members of our Board of Directors under the 2014 Plan.

Administration

The 2024 Plan will be administered by our Board of Directors. Our Board of Directors has the authority to grant awards and to adopt, amend and repeal the administrative rules, guidelines and practices relating to the 2024 Plan that it deems advisable and to construe and interpret the provisions of the 2024 Plan and any award agreements entered into under the 2024 Plan. Our Board of Directors may correct any defect, supply any omission or reconcile any inconsistency in the 2024 Plan or any award. All actions and decisions by our Board of Directors with respect to the 2024 Plan and any awards made under the 2024 Plan will be made in our Board’s discretion and will be final and binding on all persons having or claiming any interest in the 2024 Plan or in any applicable award.

Pursuant to the terms of the 2024 Plan, our Board of Directors may delegate any or all of its powers under the 2024 Plan to one or more committees or subcommittees of our Board of Directors. The Board of Directors has authorized the Compensation Committee to administer the 2024 Plan. Awards granted to non-employee directors must be granted and administered by the Board of Directors or a committee of the Board of Directors, provided that, in the event awards are granted and administered by a committee of the Board of Directors, all of the members of such committee must be independent directors as defined by Section 5605(a)(2) of the rules of the Nasdaq Stock Market.

Subject to any requirements of applicable law, the Board of Directors may, by resolution, delegate to one or more persons (including officers) or bodies, such persons or bodies, the “Delegated Persons”, the power to grant awards (subject to any limitations under the 2024 Plan) to the Company’s employees and officers, as well as to consultants and advisors of the Company (as the terms consultants and advisors are defined and interpreted for purposes of Form S-8 under the Securities Act of 1933, as amended, or any successor form) and to exercise such other powers under the 2024 Plan as the Board of Directors may determine, provided that the Board of Directors shall fix (i) the maximum number of awards, and the maximum number of shares issuable upon exercise thereof, that may be issued by such Delegated

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Persons, (ii) the time period during which such awards, and during which the shares issuable upon exercise thereof, may be issued, and (iii) the minimum amount of consideration (if any) to be received by the Company for which such awards may be issued, and a minimum amount of consideration for the shares issuable upon exercise thereof; and provided further that (I) no Delegated Person shall be authorized to grant awards to himself or herself, and (II) no Delegated Person shall be authorized to grant awards to any “executive officer” (as defined by Rule 3b-7 under the Securities Exchange Act of 1934, as amended, or the Exchange Act, or to any “officer” (as defined by Rule 16a-1(f) under the Exchange Act).

Subject to applicable limitations contained in the 2024 Plan, the Board of Directors, the Compensation Committee, or any other committee or subcommittee or Delegated Person to whom the Board of Directors has delegated authority pursuant to the 2024 Plan, as the case may be, selects the recipients of awards and determines (i) the number of shares of common stock, cash or other consideration covered by awards and the terms and conditions of such awards, including the dates upon which such awards become exercisable or otherwise vest, (ii) the exercise or measurement price of awards, if any, and (iii) the duration of awards.

Except as otherwise provided in the 2024 Plan, each award under the 2024 Plan may be made alone or in addition or in relation to any other award. The terms of each award need not be identical, and our Board of Directors need not treat participants uniformly. Our Board of Directors will determine the effect on an award of the disability, death, termination or other cessation of employment or service, authorized leave of absence or other change in the employment or other service status of a participant, and the extent to which, and the period during which, the participant (or the participant’s legal representative, conservator, guardian or designated beneficiary) may exercise rights or receive any benefits under an award.

The Board of Directors may at any time provide that any award shall become immediately exercisable in whole or in part, free from some or all restrictions or conditions or otherwise realizable in whole or in part, as the case may be. Subject to the preceding sentence, no award under the 2024 Plan shall vest earlier than the first anniversary of its date of grant, unless such award is granted in lieu of salary, bonus or other compensation otherwise earned by or payable to the participant; provided, that, such limitation will not apply to awards granted, in the aggregate, for up to 5% of the maximum number of authorized shares under the 2024 Plan.

In the event of any stock split, reverse stock split, stock dividend, recapitalization, combination of shares, reclassification of shares, spin-off or other similar change in capitalization or event, or any dividend or distribution to holders of our common stock, other than an ordinary cash dividend, we are required to make equitable adjustments (or make substituted awards, as applicable), in the manner determined by our Board of Directors, to (i) the number and class of securities available under the 2024 Plan, (ii) the number of shares issuable pursuant to incentive stock options under the 2024 Plan, (iii) the share counting rules set forth in the 2024 Plan, (iv) the number, class, exercise, measurement or purchase price and any other per share related provisions of shares subject to each outstanding award, and (v) any performance goals applicable to an award. In the event we effect a split of our common stock by means of a stock dividend and the exercise price of and the number of shares subject to an outstanding stock option are adjusted as of the date of the distribution of the dividend (rather than as of the record date for such dividend), then a participant who exercises a stock option between the record date and the distribution date for such stock dividend shall be entitled to receive, on the distribution date, the stock dividend with respect to the shares of common stock acquired upon such stock option exercise, notwithstanding the fact that such shares were not outstanding as of the close of business on the record date for such stock dividend.

We will indemnify and hold harmless each director, officer, employee or agent to whom any duty or power relating to the administration or interpretation of the 2024 Plan has been or will be delegated against any cost or expense (including attorneys’ fees) or liability (including any sum paid in settlement of a claim with our Board of Directors’ approval) arising out of any act or omission to act concerning the 2024 Plan unless arising out of such person’s own fraud or bad faith.

Amendment of Awards. Except as otherwise provided under the 2024 Plan with respect to repricing outstanding stock options or SARs and with respect to actions requiring stockholder approval, our Board of Directors may amend, modify or terminate any outstanding award, including but not limited to, substituting therefor another award of the same or a different type, changing the date of exercise or realization, and converting an incentive stock option to a nonstatutory

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stock option, provided that the participant’s consent to any such action will be required unless our Board of Directors determines that the action, taking into account any related action, does not materially and adversely affect the participant’s rights under the 2024 Plan or the change is otherwise permitted under the terms of the 2024 Plan in connection with certain corporate events.

Reorganization Events

The 2024 Plan contains provisions addressing the consequences of any reorganization event. A reorganization event is defined under the 2024 Plan as (i) any merger or consolidation of us with or into another entity as a result of which all of our common stock is converted into or exchanged for the right to receive cash, securities or other property, or is cancelled, (ii) any transfer or disposition of all of our common stock for cash, securities or other property pursuant to a share exchange or other transaction or (iii) our liquidation or dissolution.

Provisions Applicable to Awards Other than Restricted Stock. Under the 2024 Plan, if a reorganization event occurs, our Board of Directors may take any one or more of the following actions as to all or any (or any portion of) outstanding awards other than restricted stock on such terms as our Board of Directors determines (except to the extent specifically provided otherwise in an applicable award agreement, another agreement between a participant and us, or another Company plan): (i) provide that such awards shall be assumed, or substantially equivalent awards shall be substituted, by the acquiring or succeeding corporation (or an affiliate thereof), (ii) upon written notice to a participant, provide that all unvested awards will be forfeited immediately before the reorganization event and/or that all unexercised awards will terminate immediately prior to the consummation of such reorganization event unless exercised by the participant (to the extent then exercisable) within a specified period following the date of such notice, (iii) provide that outstanding awards shall become exercisable, realizable, or deliverable, or restrictions applicable to an award shall lapse, in whole or in part prior to or upon such reorganization event, (iv) make or provide for a payment in such form (which may include, without limitation, cash, cash equivalents and/or securities of the acquiring or succeeding corporation (or an affiliate thereof)) as may be determined by our Board of Directors to participants with respect to each award held by a participant equal in value to (I) the number of shares of our common stock subject to the vested portion of the award (after giving effect to any acceleration of vesting that occurs upon or immediately prior to such reorganization event) multiplied by (II) the excess, if any, of (A) the amount of cash and/or value, as determined by our Board of Directors in its discretion, of any non-cash consideration per share of common stock to be received by holders of common stock as a result of the reorganization event, or the Acquisition Price, over (B) the exercise, measurement or purchase price of such award and any applicable tax withholdings, in exchange for the termination of such award, provided, that any escrow, holdback, earn out or similar provisions in the definitive agreement governing the reorganization event may (as determined by our Board of Directors) apply to such payments to the same extent and in the same manner as such provisions apply to holders of common stock, and provided further that if the Acquisition Price does not exceed the exercise price of the award, then the award will be cancelled without any payment of consideration, (v) provide that, in connection with our liquidation or dissolution, awards shall convert into the right to receive liquidation proceeds (if applicable, net of the exercise, measurement or purchase price thereof and any applicable tax withholdings) and (vi) any combination of the foregoing.

Our Board of Directors is not obligated to treat all awards, all awards held by a participant, or all awards of the same type, identically. Certain RSU awards that are subject to Section 409A of the Code will be settled in accordance with the terms of the applicable award agreement or as otherwise specified in the 2024 Plan. Our Board of Directors, with reasonable notice to participants holding stock options or SARs, may impose a limitation on the ability of these participants to exercise their awards for the minimum number of days prior to the closing of the reorganization event as is reasonably necessary to facilitate the orderly closing of the reorganization event.

Provisions Applicable to Restricted Stock. Upon the occurrence of a reorganization event other than our liquidation or dissolution, our repurchase and other rights with respect to outstanding restricted stock will inure to the benefit of our successor and will, unless our Board of Directors determines otherwise, apply to the cash, securities or other property which our common stock was converted into or exchanged for pursuant to such reorganization event in the same manner and to the same extent as they applied to such restricted stock. However, our Board of Directors may either provide for termination or deemed satisfaction of such repurchase or other rights under the instrument evidencing any restricted stock or any other agreement between a participant and us, either initially or by amendment or provide for

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forfeiture of such restricted stock if issued at no cost. Upon the occurrence of a reorganization event involving our liquidation or dissolution, except to the extent specifically provided to the contrary in the instrument evidencing any award of restricted stock or any other agreement between the participant and us, all restrictions and conditions on all restricted stock then outstanding shall automatically be deemed terminated or satisfied.

Provisions for Foreign Participants

The Board of Directors may establish one or more sub-plans under the 2024 Plan to satisfy applicable securities, tax or other laws of various jurisdictions. The Board of Directors will establish such sub-plans by adopting supplements to the 2024 Plan containing any limitations on the Board of Directors’ discretion under the 2024 Plan and any additional terms and conditions not otherwise inconsistent with the 2024 Plan as the Board of Directors deems necessary or desirable. All supplements adopted by the Board of Directors will be deemed to be part of the 2024 Plan, but each supplement will only apply to participants within the affected jurisdiction.

Withholding

The participant must satisfy all applicable federal, state, and local or other income and employment tax withholding obligations before we will deliver stock certificates or otherwise recognize ownership of common stock under an award. We may elect to satisfy the withholding obligations through additional withholding on salary or wages. If we elect not to or cannot withhold from other compensation, the participant must pay us the full amount, if any, required for withholding or have a broker tender to us cash equal to the withholding obligations. Payment of withholding obligations is due before we will issue any shares on exercise, vesting or release from forfeiture of an award or at the same time as payment of the exercise or purchase price, unless we determine otherwise. If provided for in an award or approved by the Board of Directors, a participant may satisfy the tax obligations in whole or in part by delivery (either by actual delivery or attestation) of shares of common stock, including shares retained from the award creating the tax obligation, valued at their fair market value. However, except as otherwise provided by the Board of Directors, the total tax withholding where stock is being used to satisfy such tax obligations cannot exceed our minimum statutory withholding obligations (based on minimum statutory withholding rates for federal and state tax purposes, including payroll taxes, that are applicable to such supplemental taxable income), except that, to the extent that we are able to retain shares of common stock having a fair market value that exceeds the statutory minimum applicable withholding tax without financial accounting implications or we are withholding in a jurisdiction that does not have a statutory minimum withholding tax, we may retain such number of shares (up to the number of shares having a fair market value equal to the maximum individual statutory rate of tax) as we shall determine to be necessary to satisfy the tax liability associated with any award. Shares used to satisfy tax withholding requirements cannot be subject to any repurchase, forfeiture, unfulfilled vesting or other similar requirements.

Amendment or Termination

No award may be granted under the 2024 Plan after June 9, 2034, but awards previously granted may extend beyond that date. Our Board of Directors may amend, suspend or terminate the 2024 Plan or any portion of the 2024 Plan at any time, except that (i) no amendment may be made to the plan to permit a stock option or SAR to be repriced without stockholder approval and (ii) no amendment that would require stockholder approval under the rules of the national securities exchange on which we maintain our primary listing may be made effective unless and until such amendment has been approved by our stockholders. If the national securities exchange on which we maintain our primary listing does not have rules regarding when stockholder approval of amendments to equity compensation plans is required (or if our common stock is not then listed on any national securities exchange), no amendment of the 2024 Plan materially increasing the number of shares authorized under the plan (other than as provided under the 2024 Plan with respect to certain corporate events or substitute awards), expanding the types of awards that may be granted under the plan or materially expanding the class of participants eligible to participate in the plan will be effective unless and until our stockholders approve such amendment. If at any time the approval of our stockholders is required as to any other modification or amendment under Section 422 of the Code or any successor provision with respect to incentive stock options, our Board of Directors may not effect such modification or amendment without such approval.

Unless otherwise specified in the amendment, any amendment to the 2024 Plan adopted in accordance with the procedures described above will apply to, and be binding on the holders of, all awards outstanding under the 2024 Plan at the time the amendment is adopted, provided that our Board of Directors determines that such amendment, taking into account any related action, does not materially and adversely affect the rights of participants under the 2024 Plan. No award will be made that is conditioned on stockholder approval of any amendment to the 2024 Plan unless the

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award provides that (i) it will terminate or be forfeited if stockholder approval of such amendment is not obtained within no more than 12 months from the date the award was granted and (ii) it may not be exercised or settled (or otherwise result in the issuance of shares of our common stock) prior to the receipt of such stockholder approval.

If stockholders do not approve the 2024 Plan, the 2024 Plan will not go into effect, and we will not grant any awards under the 2024 Plan. In this event, the Board of Directors will consider whether to adopt alternative arrangements based on its assessment of our needs.

Federal Income Tax Consequences

The following is a summary of the United States federal income tax consequences that generally will arise with respect to awards granted under the 2024 Plan. This summary is based on the federal tax laws in effect as of the date of this proxy statement. In addition, this summary assumes that all awards are exempt from, or comply with, the rules under Section 409A of the Code regarding nonqualified deferred compensation. Changes to these laws could alter the tax consequences described below.

Incentive Stock Options. A participant will not have income upon the grant of an incentive stock option. Also, except as described below, a participant will not have income upon exercise of an incentive stock option if the participant has been employed by the Company or its corporate parent or 50% or more-owned corporate subsidiary at all times beginning with the stock option grant date and ending three months before the date the participant exercises the stock option. If the participant has not been so employed during that time, then the participant will be taxed as described below under “Nonstatutory Stock Options.” The exercise of an incentive stock option may subject the participant to the alternative minimum tax.

A participant will have income upon the sale of the stock acquired under an incentive stock option at a profit (if sales proceeds exceed the exercise price). The type of income will depend on when the participant sells the stock. If a participant sells the stock more than two years after the stock option was granted and more than one year after the stock option was exercised, then all of the profit will be long-term capital gain. If a participant sells the stock prior to satisfying these waiting periods, then the participant will have engaged in a disqualifying disposition and a portion of the profit will be ordinary income and a portion may be capital gain. This capital gain will be long-term if the participant has held the stock for more than one year and otherwise will be short-term. If a participant sells the stock at a loss (sales proceeds are less than the exercise price), then the loss will be a capital loss. This capital loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

Nonstatutory Stock Options. A participant will not have income upon the grant of a nonstatutory stock option. A participant will have compensation income upon the exercise of a nonstatutory stock option equal to the value of the stock on the day the participant exercised the stock option less the exercise price. Upon sale of the stock, the participant will have capital gain or loss equal to the difference between the sales proceeds and the value of the stock on the day the stock option was exercised. This capital gain or loss will be long-term if the participant has held the stock for more than one year and otherwise will be short-term.

Stock Appreciation Rights. A participant will not have income upon the grant of a SAR. A participant generally will recognize compensation income upon the exercise of a SAR equal to the amount of the cash and the fair market value of any stock received. Upon the sale of the stock, the participant will have capital gain or loss equal to the difference between the sales proceeds and the value of the stock on the day the SAR was exercised. This capital gain or loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

Restricted Stock Awards. A participant will not have income upon the grant of restricted stock unless an election under Section 83(b) of the Code is made within 30 days of the date of grant. If a timely 83(b) election is made, then a participant will have compensation income equal to the value of the stock less the purchase price, if any. When the stock is sold, the participant will have capital gain or loss equal to the difference between the sales proceeds and the value of the stock on the date of grant. If the participant does not make an 83(b) election, then when the stock vests the participant will have compensation income equal to the value of the stock on the vesting date less the purchase price, if any. When the stock is sold, the participant will have capital gain or loss equal to the sales proceeds less the value of the stock on the vesting date. Any capital gain or loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

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Restricted Stock Units. A participant will not have income upon the grant of an RSU. A participant is not permitted to make a Section 83(b) election with respect to an RSU award. When the shares of common stock are delivered with respect to the RSUs (which may be upon vesting or may be at a later date), the participant will have income on the date of delivery in an amount equal to the fair market value of the stock on such date less the purchase price, if any. When the stock is sold, the participant will have capital gain or loss equal to the sales proceeds less the value of the stock on the delivery date. Any capital gain or loss will be long-term if the participant held the stock for more than one year and otherwise will be short-term.

Other Stock-Based Awards. The tax consequences associated with any other stock-based award will vary depending on the specific terms of such award. Among the relevant factors are whether or not the award has a readily ascertainable fair market value, whether or not the award is subject to forfeiture provisions or restrictions on transfer, the nature of the property to be received by the participant under the award, and the participant’s holding period and tax basis for the award or underlying common stock.

Tax Consequences to the Company. There will be no tax consequences to the Company except that the Company will be entitled to a deduction when a participant has compensation income, subject to the limitations of Section 162(m) of the Code.

The Board of Directors recommends that stockholders vote “for” the approval of the 2024 Plan.

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TRANSACTION OF OTHER BUSINESS

Our Board of Directors knows of no other matters that will be presented for consideration at the Annual Meeting. If any other matters are properly brought before the Annual Meeting, it is the intention of the persons named in the accompanying proxy to vote on such matters in accordance with their best judgment.

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EXECUTIVE OFFICER AND DIRECTOR COMPENSATION

COMPENSATION DISCUSSION AND ANALYSIS

Executive Summary

This Compensation Discussion and Analysis discusses the principles underlying our policies and decisions with respect to the compensation of our named executive officers, and all material factors relevant to an analysis of these policies and decisions. Our named executive officers for the fiscal year ended on December 31, 2023, are:

Significant Compensation Actions

In December 2023, our Board of Directors evaluated our 2023 performance against our 2o23 corporate goals and, considering Mr. Greene’s recommendation regarding the level of achievement against each corporate goal, our Board of Directors assessed our total corporate goal achievement percentage at 82.5% for all employees, including the named executive officers.

Commencing in 2023, the Compensation Committee increased the proportion of equity awards granted as PSUs to our leadership team, other than our Chief Executive Officer, from 45% to approximately 55%, and for our Chief Executive Officer from 45% to approximately 53%, as a result of the grant of new PSUs which vest only upon our achievement of certain TSR milestones, which we refer to as the TSR Awards. Granted in March 2023, the TSR Awards are eligible for vesting based on achievement of specific levels of relative stock price performance as measured against the Nasdaq Biotechnology Index, or NBI, at the end of a three-year performance period, as discussed further below. We continued the practice of granting TSR equity awards to our leadership team in 2024.

In September 2023, Dr. Robichaud resigned as our Chief Scientific Officer, a position Dr. Robichaud had served in since Sage’s founding in 2011. In connection with Dr. Robichaud’s resignation, we entered into a separation agreement with him providing for certain severance benefits. As of April 24, 2024, Dr. Robichaud has remained in service to Sage as a scientific consultant and member of our medicinal chemistry and pre-clinical scientific advisory boards.

Stockholder Engagement and Say-on-Pay Vote Results

In evaluating our executive compensation program, our Compensation Committee considers a number of factors, including feedback we receive from our stockholders about our executive compensation program. Our Compensation Committee views stockholder feedback as an important factor in developing and improving our executive compensation program. Our stockholder outreach is a year-round effort by our management to engage with our stockholders in a continuous and meaningful way. Members of our Compensation Committee and our Nominating and Corporate Governance Committee have participated in some of these discussions.

At the 2023 annual meeting of stockholders, our annual say-on-pay proposal for our 2022 compensation program received support from 78.1% of the votes cast by our stockholders on the matter, up from 43.4% support in 2022. Between mid-2023 and early 2024, we solicited feedback from stockholders representing approximately 87% of our outstanding shares based on public filings as of December 31, 2023 and engaged with stockholders then representing approximately 67% of our outstanding shares to seek input on our corporate governance and compensation matters.

Our Compensation Committee and management team carefully evaluated stockholder feedback related to our executive compensation program in the context of our compensation philosophy, objectives, and peer practices. In response to positive stockholder feedback regarding our use of TSR awards in 2023, we have continued a similar practice in 2024,

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with a certain portion of equity awards granted to our leadership team, including our named executive officers, as PSUs including a TSR goal. In addition, in response to stockholder feedback, we have included more detailed description of our 2023 goals and the performance assessment conducted by our Board of Directors.

Corporate Background and Highlights for 2023

We are a biopharmaceutical company with a mission to pioneer solutions to deliver life-changing brain health medicines, so every person can thrive. Alongside our postpartum depression commercial products, we are targeting diseases and disorders of the brain across our clinical development and earlier stage pipeline. Our focus as a company is on brain health, and we are currently targeting two critical central nervous system, or CNS, receptor systems, GABA and NMDA. The GABA receptor family, which is recognized as the major inhibitory neurotransmitter in the CNS, mediates downstream neurologic and bodily function via activation of GABA_A receptors. The NMDA-type receptors of the glutamate receptor system are a major excitatory receptor system in the CNS. Dysfunction in these systems is implicated in a broad range of CNS disorders.

Because we have a pay-for-performance philosophy, actual compensation levels for our executive officers, including our named executive officers, are correlated to the achievement of corporate goals and individual performance. Below are our key business and performance highlights from 2023, which the Compensation Committee and Board considered when assessing the Company’s performance against the 2023 corporate goals for the purposes of funding the Annual Bonus Incentive Plan for 2023 for all employees, including our named executive officers:

Compensation Philosophy and Objectives

Our Compensation Committee believes that a well-designed compensation program should align executive interests with the drivers of growth and stockholder return, including by supporting our achievement of our primary business goals and our ability to attract and retain employees whose talents, expertise, leadership, and contributions are expected to build and sustain growth in long-term stockholder value. As a result, we maintain a strong pay-for-performance orientation in our compensation program by making a significant portion of total compensation variable and dependent on performance against goals, by differentiating awards based on individual performance, and, beginning in March 2023, by tying the vesting of certain PSU awards made to our leadership team to specified TSR milestones, all of which are intended to align our compensation program with stockholder interests.

To achieve these objectives, our Compensation Committee regularly reviews our compensation policies and overall program design to ensure that they are aligned with the interests of our stockholders and our business goals, and that the total compensation paid to our employees and directors is fair, reasonable and competitive for our size and stage of development. Specifically, for our executive officers, our Compensation Committee targets base salaries within a market-competitive range for our peer group and targets annual cash bonuses and annual long-term equity incentive awards around the market median for our peer group, with variability in actual payments based on corporate and individual performance.

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Key Performance Factors in Determining Executive Compensation

The biopharmaceutical industry is characterized by a very long product development cycle, including a lengthy research and development period and a rigorous regulatory approval process, including the requirements for multiple phases of human testing and the need to meet a significant number of other government requirements. We are heavily focused on the commercialization of ZURZUVAE for women with PPD, and we continue to focus on advancing our clinical-stage product candidates and on research and development. Accordingly, our Compensation Committee believes that the following performance factors may best support our future growth:

Executive Compensation Elements

Key elements of our compensation programs include the following:

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Other Compensation Practices

In addition to our compensation elements, the following compensation program features are designed to align our executive team’s interests with stockholder interests and market best practices:

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Target Pay

Our Compensation Committee exercises its judgment to determine what it believes to be the appropriate level and mix of the various compensation components, after a rigorous process of reviewing benchmark information provided by the Compensation Committee’s compensation consultant and other relevant data on market practices. We strive to provide our executive officers with a balance of short-term and long-term incentives to encourage and reward consistently strong performance. Approximately 88% of our 2023 compensation for our Chief Executive Officer and approximately 73% of our 2023 compensation for our other executive officers, including our other named executive officers, was variable, at risk and based on performance. Ultimately, the objective in setting the balance between long-term and short-term compensation is to ensure adequate base and short-term incentive compensation to attract and retain talent, while providing incentives to maximize long-term value for the Company and our stockholders.

Roles and Executive Compensation Process

Role of our Compensation Committee – Our Compensation Committee is responsible for, among other things, reviewing and approving, or recommending for approval by our Board of Directors, the compensation of our executive officers and certain other members of our leadership team, including salary, bonus and incentive compensation levels, equity compensation (including awards to induce employment), severance arrangements, change-in-control benefits and other forms of executive officer compensation. A full description of the Compensation Committee’s role and responsibilities is in the Compensation Committee’s written charter, which was adopted by the Board of Directors and is available on our website at http://investor.sagerx.com/corporate-governance.

Goalsetting and Performance Assessment – Annual corporate goals and strategic milestone goals used as PSU vesting triggers are proposed by our leadership team in December of a given year or in the first quarter of the next year, reviewed by our Compensation Committee, and approved by our Board of Directors. During the same period, our Compensation Committee, with the input of the leadership team, evaluates our annual corporate performance against the prior year’s corporate goals, and taking into account other factors relevant to corporate performance, assigns an annual corporate performance rating which is then assessed and approved by the full Board of Directors. Our strategic milestone goals used as PSU vesting triggers are set by our Board of Directors and assessed on an ongoing basis.

Decision Process – Typically during the first quarter of each year, our Compensation Committee determines the compensation for such year for each of the executive officers other than our Chief Executive Officer and submits a compensation recommendation to our Board of Directors for our Chief Executive Officer. Our Board of Directors then determines the compensation for such year for our Chief Executive Officer. The compensation determination for our Chief Executive Officer and our other executive officers, including the amount of any annual equity awards, the amount of any cash incentive payments, and any changes in base salary, are in each case based on the prior year’s overall corporate performance against the established corporate goals, as well as each individual executive officer’s contributions to the achievement of the corporate goals and individual performance. Bonuses paid under our Annual Bonus Incentive Plan are typically paid in the first quarter of the calendar year. Our Compensation Committee may also periodically review the compensation of our executive officers throughout the course of the year.

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Role of Management – As a part of determining named executive officer performance and compensation, the Compensation Committee receives recommendations from our Chief Executive Officer (except with respect to the Chief Executive Officer’s own compensation and performance). Our Chief Executive Officer’s performance and compensation is approved by our Board of Directors based upon the recommendation of the Compensation Committee. The evaluation of each of our named executive officers is based on our overall corporate performance against annual goals that are approved by our Board of Directors at the beginning of each year, in addition to a review of individual performance.

Role of the Compensation Committee’s Independent Compensation Consultant – For 2023, our Compensation Committee engaged Alpine Rewards, or Alpine, as its independent compensation consultant to advise on executive compensation matters including overall compensation program design, peer group development and updates, and collecting market data to inform our compensation programs for our executives and members of our Board of Directors. Alpine advises the Compensation Committee on all of the principal aspects of executive compensation, including executive new hire compensation arrangements. Alpine consultants attend meetings of the Compensation Committee when requested to do so. Alpine reports directly to our Compensation Committee and not to management, although it meets with management for purposes of gathering information for its analyses and recommendations. Our Compensation Committee has assessed the independence of Alpine consistent with Nasdaq listing standards and has concluded that the engagement of Alpine does not raise any conflict of interest.

Defining and Comparing Compensation to Market Benchmarks

In evaluating the total compensation of our named executive officers, our Compensation Committee reviews publicly available compensation data and survey data provided by our compensation consultant from a peer group. Our Compensation Committee considered companies with the following criteria when establishing our peer group for 2023 compensation decisions:

In addition to a peer group determined using the above criteria, our Compensation Committee also considered companies which list Sage as a peer in their compensation disclosures. The Compensation Committee also uses competitive compensation data from the annual total compensation study of peer companies to inform its decisions about overall compensation opportunities and specific compensation elements.

In determining the 2023 compensation for our named executive officers, our Compensation Committee relied on the following peer group prepared by Alpine and approved by the Compensation Committee in September 2022, which we call our 2023 Peer Group:

Changes as compared to the peer group approved for 2022 included removal of Acceleron Pharmaceuticals, Inc., Biohaven Pharmaceuticals, Inc., Epizyme, Inc. and Global Blood Therapeutics, Inc., each of which was acquired, and bluebird bio and Nektar Therapeutics, each of which fell outside of our market capitalization range criteria. Six

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additional companies meeting our criteria, Amicus Therapeutics, Inc., Apellis Pharmaceuticals, Inc., CRISPR Therapeutics AG, Halozyme Therapeutics, Inc., Mirati Therapeutics, Inc., and Sorrento Therapeutics, Inc., were added to our 2023 Peer Group, for a total of seventeen companies, which the Compensation Committee believed provides a meaningful sample for quality benchmarking.

At the time the 2023 Peer Group was approved, the 30-day average market capitalization of each organization was approximately $3.09 billion, median revenue was $230 million and median research and development expense was $324 million. We believe that the compensation practices of our 2023 Peer Group provided us with appropriate compensation reference points for evaluating the compensation of our named executive officers during 2023. The Compensation Committee also considers other reference points and criteria, including market factors and competition for executive talent, when establishing targeted compensation levels, such as the executive’s experience level, contributions in helping to achieve our goals, individual performance against the executive’s individual goals where applicable, scope of responsibility, skill sets, and leadership potential, as well as our critical needs and succession planning.

Our Compensation Committee reviews the companies in our peer group annually and makes adjustments as necessary to ensure the peer group continues to properly reflect the market in which we compete for talented executives and to ensure the companies in the peer group remain appropriate. For purposes of executive compensation for 2024, our Compensation Committee, with the advice of Alpine, recommended no change to our peer group criteria and examined our 2023 Peer Group in light of our stage of growth as a commercial company, the stage of development of our clinical programs and changes in our market capitalization, among other considerations. With reference to these and other key business metrics, companies whose market capitalization no longer met our criteria and/or whose stage of development was no longer comparable to our stage of development were removed and new companies were added to our peer group that better aligned with our stage of development and market capitalization. Exelixis, Inc. and FibroGen, Inc. were removed from our peer group due to their market capitalization not meeting our criteria, and Sorrento Therapeutics, Inc. was removed due to filing for bankruptcy. To replace the companies that were removed, six biopharmaceutical companies that met our peer group criteria—Amylyx Pharmaceuticals, Inc., Axsome Therapeutics, Inc., Cerevel Therapeutics, Inc., Rhythm Pharmaceuticals, Inc., and Supernus Pharmaceuticals, Inc.—were added to our revised peer group. In September 2023, our Compensation Committee approved the revised peer group, which we refer to as our 2024 Peer Group, consisting of the following companies:

Base Salary

Base salary is intended to provide compensation for day-to-day performance. The Compensation Committee believes that a competitive base salary is a necessary element of any compensation program that is designed to attract and retain talented and experienced executives. Base salaries for our executive officers are intended to be competitive with those received by other individuals in similar positions at the companies with which we compete for talent. Base salaries are originally established at the time the executive is hired based on individual experience, skills and expected contributions, our understanding of what executives in similar positions at peer companies are paid, and negotiations during the hiring process. The base salaries of our executive officers are reviewed annually and may be adjusted to reflect market conditions and our executives’ performance during the prior year as well as our financial position, or if there is a change in the scope of the officer’s responsibilities.

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At the beginning of 2023, our Compensation Committee approved increases in base salary for each of our named executive officers, based upon the named executive officer’s individual performance and the comparison of his or her base salary to the base salaries of executive officers in comparable positions in our 2023 Peer Group. Each salary adjustment was retroactive to January 1, 2023. The table below sets forth the adjustments made in 2023 to the 2022 base salary, in dollars and as a percentage:

Short-Term Incentives – Performance-Based Annual Bonus Incentive Plan

The Compensation Committee reviews the competitiveness of our Annual Bonus Incentive Plan targets annually. No changes were made to incentive targets for executive officers in 2023.

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Short-Term Incentives – Performance-Based Annual Bonus Incentive Plan Corporate Goals Assessment

In making its determination regarding bonuses based on performance in 2023 under our annual cash incentive program, our Compensation Committee considered our performance against our 2023 corporate goals and other considerations reflecting the Company’s significant accomplishments in 2023. The 2023 corporate goals and the weight attributable to each goal were approved by our Board of Directors in the first quarter of 2023. In December 2023, the Board of Directors evaluated our 2023 performance against our corporate goals and considered Mr. Greene’s recommendation regarding the level of achievement against each goal. The Board of Directors assessed the Company’s total corporate goal achievement percentage at 82.5% for all employees, including the named executive officers, which balanced the Company’s significant accomplishments in 2023, including receiving FDA approval for, and making commercially available, ZURZUVAE for the treatment of women with PPD, with the Company’s receipt of a Complete Response Letter for zuranolone for the treatment of major depressive disorder, or MDD, in August 2023. A summary of the corporate goals, relative weightings, level of achievement is set forth in the table below:

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Calculation of Annual Cash Incentives

Our Compensation Committee establishes the annual performance-based cash bonus opportunity for each member of our leadership team other than our Chief Executive Officer, representing a percentage of each individual’s base salary. In January 2024, the Compensation Committee assessed the individual performance of each of our named executive officers other than Mr. Greene and Dr. Robichaud. Mr. Greene’s bonus as Chief Executive Officer was determined solely on the basis of the corporate performance level, and therefore received a bonus equal to 82.5% of his target bonus for 2023. Dr. Robichaud resigned in September 2023, and under the terms of his separation agreement, described further below, he received a pro-rated bonus equal to 60% of his bonus target for 2023. The bonuses paid to our named executive officers excluding Mr. Greene and Dr. Robichaud were a function of both the corporate performance level and individual performance relative to our corporate goals.

When assessing the individual performance of the named executive officers other than Mr. Greene and Dr. Robichaud, the Compensation Committee considered the following contributions to our corporate goals:

Ms. Iguchi. Under Ms. Iguchi’s leadership in 2023, we delivered a robust long-range plan and analysis that provided visibility on key financial metrics, risks and opportunities, and enabled enhanced forecasting and contingency planning. These enhancements supported our management and program teams in key strategic decisions, including in connection with our financing and commercialization strategies and efficient management of operating expenses. Throughout 2023, Ms. Iguchi also drove timely forward-looking analyses and insights, generated multiple business cases for various programs, and facilitated agile investment planning, allowing rapid adjustments to support our strategic reorganization and the extension of our cash runway. Throughout 2023, Ms. Iguchi strategically executed investor outreach and targeting. In addition, Ms. Iguchi oversaw the process to select a new location for our corporate headquarters, ultimately executing a lease that we expect will result in a significant reduction of our Cambridge real estate footprint and related lease and operating expenses.

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Mr. Benecchi. Under Mr. Benecchi’s leadership in 2023, we developed and implemented zuranolone launch readiness planning and made ZURZUVAE commercially available to treat women with PPD in December 2023. In preparation for commercial availability and launch of ZURZUVAE, Mr. Benecchi led development of our go-to-market strategies and operating plans and built relationships with national, regional and government payors, including to advocate for broad and equitable access to ZURZUVAE for women with PPD with minimal restrictions. In addition, Mr. Benecchi provided key inputs for strategic decisions relating to our investment plans, marketing, market access, distribution, branding, and forecasting, including to assist with development of our short- and long-term business planning efforts.

Dr. Gault. Under Dr. Gault’s leadership in 2023, our team achieved significant regulatory milestones, including those associated with the filing of the NDA for zuranolone and resulting in the FDA’s approval of ZURZUVAE for the treatment of women with PPD and the overall label obtained for ZURZUVAE. Dr. Gault made key contributions in 2023 to bolster clinical trial enrollment and establish oversight and data quality initiatives, which helped lead to the early completion of enrollment for several of our clinical trials. Throughout 2023, Dr. Gault developed relationships with key internal and external stakeholders to advance our mission. In addition, Dr. Gault played an instrumental role in our ongoing efforts to integrate our health economics and outcomes research plans into our overall program strategy.

Ms. Cook. Under Ms. Cook’s leadership in 2023, our legal, compliance and intellectual property teams provided pragmatic guidance and solutions on a range of key strategic and business execution matters, including our efforts to gain regulatory approval of zuranolone in the U.S.; our permitted pre-launch and commercial launch activities following the FDA’s approval of ZURZUVAE for the treatment of women with PPD; and other key activities. Throughout 2023, Ms. Cook provided key input and guidance on efforts to support our strong culture of integrity and compliance and with respect to our ongoing collaborations, commercialization efforts, contracting strategy, onboarding and training of personnel, and research and development.

The table below shows, for each named executive officer, such executive’s target cash incentive award under the 2023 annual cash incentive program as a percentage of the named executive officer’s annual base salary in 2023, the target cash incentive award opportunity in dollars for 2023, our Company performance factor based on the Board of Directors’ assessment of our corporate performance, each individual’s performance factor based on an assessment of individual performance, and the actual cash incentive award payments to our named executive officers for 2023 performance, which were paid in February 2024. To calculate each award payment, we multiplied the applicable named executive officer’s target cash incentive award opportunity by both the corporate and individual performance-level multipliers.

2023 Performance-Based Annual Cash Incentive Awards

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Long-Term Incentives – Equity Incentive Compensation

The market for qualified and talented executives in the biopharmaceutical industry is highly competitive, and we compete for talent with many companies that have greater financial resources than we do. Accordingly, we believe equity compensation is a crucial component of any competitive executive compensation package we offer. We typically grant equity awards to each of our executive officers upon commencement of employment; annually in conjunction with our review of individual performance; in connection with a promotion; or as a special incentive.

In determining the annual equity awards to grant to any of our executive officers, which includes our named executive officers, the Compensation Committee typically considers a number of factors, including: our performance against corporate goals during the preceding year, the executive officer’s individual performance during the preceding year, the executive officer’s ability to drive future value creation, the overall retention value of past equity awards, and competitive levels of executive compensation for similarly situated executive officers based on analysis of data from our applicable peer group. In addition, our Compensation Committee reviews all components of the executive officer’s compensation to ensure that his or her total compensation is aligned with our overall philosophy and objectives.

Equity awards for our employees, including our executive officers, take the form of stock options with time-based vesting, RSUs with time-based vesting, and PSUs. As a company that relies heavily on the use of stock options to align the interests of employees, including our executive officers, with the interests of stockholders, we do not believe that the Black-Scholes accounting value (calculated in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718, “Compensation—Stock Compensation”, or FASB Topic 718) should be the primary determinant of award size. We believe stock price volatility is inherent in the drug development industry, and we do not believe that employees should be rewarded with more shares due to decreases in our stock price or penalized with fewer shares due to increases in our stock price. Therefore, we focus on percentage ownership and managing dilution, which we believe are important to our stockholders and provide greater continuity from year to year for our employees. We then validate our assessment with a review of the applicable Black-Scholes accounting values to ensure the market competitiveness of our incentive programs is evaluated holistically.

To this end, we use a unit-based approach to determine equity awards for all employees, including our executive officers, and consider the percent ownership of the Company being awarded as the primary measure for targeting competitive awards. We align the overall pool of equity to be awarded to our executive officers with the median competitive range and allow for some flexibility within that range, dependent on business needs, with sensitivity towards short-, medium-and long-term dilution. Black-Scholes accounting value (calculated in accordance with FASB Topic 718) and current realizable value of historical awards are factors also considered to help ensure appropriate stewardship of the equity plan and reasonable delivery to equity recipients. To establish specific market competitive equity guidelines for our executive officers, we apply the percent ownership of the Company being awarded, using stock options as our benchmark for measurement.

For our executive officers, including our named executive officers, in 2022 we split the total number of shares subject to equity awards 55%/45% between stock options with time-based vesting and PSUs. The shares subject to PSUs only vest upon the achievement of pre-defined strategic milestone goals and are subject to the risk of forfeiture if the applicable goals are not achieved. In 2023, we increased our emphasis on PSUs by adding a TSR-based vesting component and splitting the total number of shares subject to equity awards 47%/53% between stock options with time-based vesting and PSUs for our CEO, and 45%/55% for our other named executive officers. This change was driven by our pay-for-performance philosophy and feedback we received from our stockholders.

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A portion of the PSUs granted to our named executive officers in 2023 vest upon the achievement of strategic regulatory and commercial milestones approved by our Board of Directors. We believe these milestones, summarized as follows, are aligned with potential value creation for our stockholders over a span of one to five years:

In addition, commencing in 2023, a portion of the PSUs granted to our named executive officers vest only upon the achievement of certain TSR milestones. Granted in March 2023, the TSR Awards are eligible for vesting based on achievement of specific levels of relative stock price performance as measured against the NBI at the end of the three-year performance period between January 1, 2023 and December 31, 2025, as set forth below:

The following summarizes milestone activity under historical PSU awards during 2023:

All stock options granted to our executive officers have exercise prices equal to the fair market value of our common stock on the date of grant, so that the recipient will not earn any compensation from his or her options until they are vested and unless our share price increases above the share price on the date of grant. Stock options granted to our executive officers have time-based vesting, typically vesting as to 25% of the shares on the first anniversary of their hire date or date of grant and then in equal monthly installments thereafter until the fourth anniversary of such date subject to the executive officer’s continued employment through each such date, which we believe provides an incentive to our

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executives to add value to the Company over the long-term and to remain with Sage. Vesting of option and PSU grants to employees typically ceases upon termination of employment, and option exercise rights typically cease three months following termination of employment, except in the case of death or disability or where the Compensation Committee or the Board of Directors has exercised its authority to extend the relevant option exercise time period. Prior to the exercise of an option and the vesting and settlement of PSUs, the grantee does not have any rights as a stockholder with respect to the applicable shares underlying the equity awards, including voting rights and the right to receive dividends or dividend equivalents.

All equity awards to our named executive officers are approved by our Compensation Committee, other than equity awards to our Chief Executive Officer, which are approved by the Board of Directors upon a recommendation by the Compensation Committee.

Annual equity awards to our named executive officers other than our Chief Executive Officer are typically granted at one of the first few regularly scheduled meetings of the Compensation Committee of the calendar year. Equity awards vary in size among our executive officers. Because Dr. Gault was hired in October 2022, she received a pro-rated portion of her annual grant in 2023.

A summary of the 2023 annual equity awards granted to each of our named executive officers is shown in the table below:

Executive Officer Stock Ownership Guidelines

Because of the importance of linking the interests of management and stockholders, in 2015, our Compensation Committee established stock ownership guidelines for our executive officers. These guidelines specify the number of shares that our executive officers must accumulate and hold within five years from the later of the effective date of implementation of the guidelines or the date the individual was hired or promoted to an executive officer position. Under the guidelines, ownership targets are set at a value greater than or equal to four times base salary in the case of our Chief Executive Officer, and greater than or equal to two times base salary in the case of our other executive officers. The following forms of equity are counted as owned for purposes of the stock ownership guidelines: shares

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owned outright; unvested restricted stock units (whether or not performance-based); and vested but unexercised “in-the-money” stock options. We conducted our most recent periodic assessment on the basis of ownership as of June 15, 2023, and all executive officers who were required to be in compliance with our ownership guidelines by that date were in compliance. The Compensation Committee oversees compliance with the stock ownership guidelines and periodically reviews and amends the stock ownership guidelines as the Compensation Committee deems advisable.

Stock Option Granting Practices

Delegation to Our Chief Executive Officer

Currently, all of our employees, including our named executive officers, are eligible to participate in the 2014 Plan. Currently, all new employees are granted stock options when they start employment under the 2014 Plan, and all continuing employees are eligible for equity awards on an annual basis under the 2014 Plan based on performance and upon promotions to positions of greater responsibility. Our Compensation Committee has delegated to our Chief Executive Officer the authority to make equity awards under our 2014 Plan within approved guidelines to new hires, to non-employee consultants, and in connection with annual grants and promotions, other than grants to leadership team members who directly report to the Chief Executive Officer, which include all executive officers. The number of stock options or other equity awards our Chief Executive Officer may grant under the 2014 Plan to any individual must be within the range set by our Compensation Committee for these awards.

With respect to stock option awards to new hires made under the 2014 Plan, the award is typically granted to the new hire on the first business day of the calendar month following the date of his or her first date of employment.

Employee Benefits

In addition to the primary elements of compensation described above, the named executive officers participate in the same broad-based employee benefits programs available to all of our employees, including health insurance, life and disability insurance, dental insurance and our 401(k) plan. We do not provide special benefits to our executive officers.

Compliance with IRS Code Section 162(m)

We are generally entitled to a U.S. federal income tax deduction with respect to compensation income paid to our service providers, subject to limitation under Section 162(m) of the Internal Revenue Code of 1986, as amended, with respect to compensation in excess of $1 million paid in any one year to each of certain of the company’s current and former executive officers. The Compensation Committee has and will continue to review on a periodic basis the potential effect of Section 162(m) and may use its judgment to authorize compensation payments that may be in excess of the limit when it believes such payments are appropriate and in the best interests of our company and our stockholders.

Rule 10b5-1 Sales Plans

Our policy governing transactions in our securities by directors, officers and employees permits our directors, officers and employees to enter into trading plans complying with Rule 10b5-1 under the Exchange Act. Certain of our executive officers have adopted, and directors and other executive officers may in the future adopt, Rule 10b5-1 trading plans. Generally, under these trading plans, the individual relinquishes control over the transactions once the trading plan is put into place. Accordingly, sales under these plans may occur at any time during the term of the trading plan, including possibly before, simultaneously with, or immediately after significant events involving the Company, and at other times, including during a closed trading window, when a director, officer, or employee may otherwise be prohibited from trading. The first transaction under a 10b5-1 plan adopted on or after February 27, 2023, for directors and members of our leadership team may occur no earlier than the later of: (i) 90 days following the plan adoption or modification or (ii) two business days following the disclosure in a periodic report of our financial results for the fiscal quarter in which the plan was adopted or modified (up to a maximum of 120 days following plan adoption or modification). The first transaction under a 10b5-1 plan adopted on or after February 27, 2023, for other persons (excluding directors and members of our leadership team) may occur no earlier than 60 days following the plan adoption or modification. The directors, officers and employees who are parties to such sales plans may amend or terminate the plans in certain circumstances.

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Compensation Risk Assessment

Our Compensation Committee periodically reviews and considers whether our compensation programs and policies create risks that are reasonably likely to have a material adverse effect on us. We believe that our executive compensation program does not encourage excessive or unnecessary risk-taking. This is primarily due to the fact that our compensation programs are designed to encourage our executive officers and other employees to remain focused on both short-term and long-term strategic goals. We also have a Values Code in place designed to prevent conduct by our executive officers and other employees that is inconsistent with applicable laws and regulations. Our Values Code serves as the foundation of our corporate governance principles. Disciplinary measures for violations of our Values Code may include a reduction or elimination of bonuses, termination of employment or restitution. We have established several controls to address and mitigate compensation-related risk, such as maintaining an anti-hedging and anti-pledging policy, stock ownership guidelines for our executives and non-employee directors, and a clawback policy to recover cash and equity incentive awards in connection with certain events, as described below. In addition, the stock option agreements that govern stock options granted to our executive officers and other employees provide that the options will terminate in the event of termination of the individual’s employment “for cause.” As a result, we do not believe that our compensation programs are reasonably likely to have a material adverse effect on us.

Clawback Policy

Our Board of Directors adopted an updated clawback policy, effective as of October 2, 2023, in accordance with Rule 10D-1 of the Exchange Act, and Nasdaq listing standards that is applicable to all of our current or former executive officers, or the Covered Persons. The clawback policy is administered by our Compensation Committee. In the event we are required to prepare an accounting restatement due to material noncompliance with any financial reporting requirement under U.S. federal securities laws, including any required restatement to correct an error in previously issued financial statements that is material to the previously issued financial statements or that would result in a material misstatement if the error were corrected in the current period or left uncorrected in the current period, it is our policy to recover reasonably promptly the amount of erroneously awarded incentive-based compensation received by Covered Persons. The recovery of such compensation applies regardless of whether an executive engaged in misconduct or otherwise caused or contributed to the requirement for the accounting restatement.

Compensation Committee Report

Our Compensation Committee has reviewed and discussed the “Compensation Discussion and Analysis” required by Item 402(b) of Regulation S-K with management. Based upon such review and discussions, our Compensation Committee recommended to our Board of Directors that such section be included in this Proxy Statement and incorporated by reference in our Annual Report on Form 10-K for the year ended December 31, 2023, which was filed with the SEC on February 14, 2024.

By the Compensation Committee of the Board of Directors of Sage Therapeutics, Inc.,

Michael F. Cola, Chair

Elizabeth Barrett

James M. Frates

Securities Authorized for Issuance Under Equity Compensation Plans

The following table sets forth information as of December 31, 2023, regarding shares of our common stock that may be issued under our equity compensation plans, consisting of the 2011 Plan, the 2014 Plan, the 2014 ESPP, and our 2016 Inducement Plan. Since the closing of our initial public offering, no additional equity awards have been made under our 2011 Plan. Our 2014 Plan contains an “evergreen” provision, which allows for an annual increase in the number of shares of stock available for issuance on the first day of each year. The annual increase in the number of shares is a maximum of four percent of the number of shares of our common stock issued and outstanding on the immediately preceding December 31, or such lesser number of shares determined by our Board of Directors or Compensation Committee. On April 16, 2024, our Board of Directors approved an amendment to the 2016 Inducement Plan to reduce the number of shares available for grant thereunder, such that no future awards may be granted under the 2016 Inducement Plan following the date of such amendment, but awards previously granted under the 2016 Inducement Plan will remain outstanding.

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Equity Compensation Plan Information as of December 31, 2023

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Executive Compensation

2023 Summary Compensation Table

The following table sets forth the compensation earned during the fiscal years ended December 31, 2023, December 31, 2022, and December 31, 2021 for our chief executive officer, our chief financial officer, our next three highest-paid executive officers in 2023, and our former chief scientific officer, in accordance with applicable SEC rules. We refer to these officers as our named executive officers.