UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No. )

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Sage Therapeutics, Inc.

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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on June 5, 2019. SAGE THERAPEUTICS, INC. SAGE THERAPEUTICS, INC. 215 FIRST STREET CAMBRIDGE, MA 02142 E77537-P22410 Meeting Information Meeting Type: Annual Meeting For holders as of: April 8, 2019 Date: June 5, 2019 Time: 9:00 a.m. Eastern Time Location: Company Headquarters 215 First Street Cambridge, Massachusetts 02142 You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. proxy See the materials reverse and side voting of this instructions. notice to obtain

Before You Vote How to Access the Proxy Materials Proxy Materials Available to VIEW or RECEIVE: NOTICE AND PROXY STATEMENT ANNUAL REPORT How to View Online: Have the information that is printed in the box marked by the arrowï§XXXX XXXX XXXX XXXX (located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL*: sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrowï§XXXX XXXX XXXX XXXX (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 22, 2019 to facilitate timely delivery. How To Vote Please Choose One of the Following Voting Methods Vote In Person: Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares. P22410 Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box—marked by the arrow §XXXX XXXX XXXX XXXX (located on the following page) available and follow the instructions. E77538 Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.

Voting Items The Board of Directors recommends you vote FOR the following: 1. Election of Directors Nominees: 01) Kevin P. Starr 02) James M. Frates 03) George Golumbeski, Ph.D. The Board of Directors recommends you vote FOR proposals 2 and 3. 2. To ratify the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2019. 3. To hold a non binding advisory vote to approve the compensation paid to our named executive officers. NOTE: To transact such other business as may properly come before the meeting or at any and all adjournments or postponements thereof. - P22410 E77539

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