Form of Restricted Stock Unit Agreement under the 2024 Equity Incentive Plan

Sage Therapeutics, Inc.

RESTRICTED STOCK UNIT AGREEMENT

Granted under 2024 Equity Incentive Plan

Sage Therapeutics, Inc. (the “Company”) hereby grants the following restricted stock units to the recipient named below pursuant to its 2024 Equity Incentive Plan (as amended through the date hereof, the “Plan”). The terms and conditions attached hereto are also a part hereof and incorporated herein by reference.

Notice of Grant

Vesting Schedule:

For so long as Participant remains an Eligible Participant (as defined in Section 3 hereof) on the relevant date, the RSUs shall vest as set forth below.

This grant of RSUs satisfies in full all commitments that the Company has to the Participant with respect to the issuance of stock, stock options or other equity securities.

Sage Therapeutics, Inc.

Restricted Stock Unit Agreement

Incorporated Terms and Conditions

1. Award of Restricted Stock Units.

The Company has granted to the Participant, subject to the terms and conditions set forth in this Restricted Stock Unit Agreement (this “Agreement”) and in the Plan, an award with respect to the number of restricted stock units set forth in the Notice of Grant that forms part of this Agreement (the “Notice of Grant”). Each RSU represents the right to receive one share of common stock, $0.0001 par value per share, of the Company (“Common Stock”) upon vesting of the RSU, subject to the terms and conditions set forth herein.

2. Vesting.

The RSUs shall vest in accordance with the vesting schedule set forth in the Notice of Grant (the “Vesting Schedule”). Any fractional shares resulting from the application of any percentages used in the Vesting Schedule shall be rounded down to the nearest whole number of RSUs. As soon as practicable after the vesting of the RSU, the Company will deliver to the Participant, for each RSU that becomes vested, one share of Common Stock, subject to the payment of any taxes pursuant to Section 7. The Common Stock will be delivered to the Participant as soon as practicable following each vesting date, but in any event within 30 days of such date.

3. Termination of Employment with the Company.

In the event that the Participant ceases to be an Eligible Participant (as defined below) for any reason, all of the RSUs that are unvested as of the time of such cessation shall be forfeited immediately and automatically to the Company, without the payment of any consideration to the Participant, effective as of such cessation. Upon forfeiture of any unvested RSUs, the Participant shall have no further rights with respect to the unvested RSUs or any Common Stock that may have been issuable with respect thereto.

The Participant shall be an “Eligible Participant” if he or she is an employee of the Company or any other entity the employees of which are eligible to receive RSUs under the Plan. Notwithstanding anything to the contrary in this Agreement, neither the Company nor any subsidiary is obligated, by or as a result of the Plan or this Agreement, to continue the Participant as an employee of the Company or any subsidiary, and neither the Plan nor this Agreement shall interfere in any way with the right of the Company or any subsidiary to terminate the employment of the Participant with the Company or any subsidiary at any time.

4. Transfer Restrictions; Clawback.

(a) The RSUs may not be sold, assigned, transferred, pledged, encumbered or otherwise disposed of by the Participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution. The Company shall not be required to treat as the owner

of any RSUs or issue any Common Stock to any transferee to whom such RSUs have been transferred in violation of any of the provisions of this Agreement.

(b) In accepting the RSUs, the Participant agrees to be bound by any clawback policy that the Company has in place or may adopt in the future, including without limitation Sage Therapeutics’ Compensation Recovery Policy adopted in accordance with stock exchange listing requirements (or any successor policy).

5. Rights as a Stockholder.

The Participant shall have no rights as a stockholder of the Company with respect to any shares of Common Stock that may be issuable with respect to the RSUs until the issuance of the shares of Common Stock to the Participant following the vesting of the RSUs. For the avoidance of doubt, the Participant shall have no right to vote the shares of Common Stock subject to the RSUs unless and until such shares are issued to the Participant and the Participant shall have no right to receive dividends with respect to the shares of Common Stock subject to the RSUs unless and until such shares are issued to the Participant.

6. Provisions of the Plan.

This Agreement is subject to the provisions of the Plan (including the provisions relating to amendments to the Plan), a copy of which is furnished to the Participant with this Agreement.

7. Tax Matters.

(a) Acknowledgments; No Section 83(b) Election. The Participant acknowledges that he or she is responsible for obtaining the advice of the Participant’s own tax advisors with respect to the award of RSUs and the Participant is relying solely on such advisors and not on any statements or representations of the Company or any of its agents with respect to the tax consequences relating to the RSUs. The Participant understands that the Participant (and not the Company) shall be responsible for the Participant’s tax liability that may arise in connection with the acquisition, vesting and/or disposition of the RSUs. The Participant acknowledges that no election under Section 83(b) of the Internal Revenue Code of 1986, as amended, (the “Code”) is available with respect to RSUs.

(b) Withholding. [The minimum tax withholding obligation arising from vesting of the RSUs will be satisfied through withholding by the Company from shares of Common Stock to be issued to the Participant a number of shares of Common Stock with an aggregate fair market value (as determined by the Company) that would satisfy the withholding amount due.] OR [The Participant acknowledges and agrees that the Company has the right to deduct from payments of any kind otherwise due to the Participant any federal, state, local or other taxes of

any kind required by law to be withheld with respect to the vesting of the RSUs. To the extent the Grantee has not previously executed and delivered to the Company effective durable sell-to-cover instructions that by their terms would cover any taxes required by law to be withheld with respect to the vesting of the RSUs, at such time as the Participant is not aware of any material nonpublic information about the Company or the Common Stock and is not prohibited from doing so by the Company’s insider trading policy or otherwise, the Participant shall execute the instructions set forth in Schedule A attached hereto (the “Durable Automatic Sell-to-Cover Instruction”) as the means of satisfying such tax obligation. If the Participant is required to but does not execute the Durable Automatic Sell-to-Cover Instruction prior to an applicable vesting date, then the Participant agrees that if under applicable law the Participant will owe taxes at such vesting date on the portion of the award then vested the Company shall be entitled to immediate payment from the Participant of the amount of any tax required to be withheld by the Company. The Company shall not deliver any shares of Common Stock to the Participant until it is satisfied that all required withholdings have been made.]

8. Section 409A.

The RSUs awarded pursuant to this Agreement are intended to be exempt from or comply with the requirements of Section 409A of the Code and the Treasury Regulations issued thereunder (“Section 409A”). The delivery of shares of Common Stock on the vesting of the RSUs may not be accelerated or deferred unless permitted or required by Section 409A.

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Schedule A

DURABLE AUTOMATIC SELL-TO-COVER INSTRUCTION

This Durable Automatic Sell-to-Cover Instruction (this “Instruction”), which is being delivered to Sage Therapeutics, Inc. (the “Company”) by the undersigned on the date set forth below (the “Adoption Date”), relates to the Covered RSUs (as defined following my signature below). This Instruction provides for “eligible sell-to-cover transactions” (as described in Rule 10b5-1(c)(1)(ii)(D)(3) under the Securities Exchange Act of 1934 (the “Exchange Act”)) with respect to the Covered RSUs and is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c)(1) under the Exchange Act.

I acknowledge that upon vesting and settlement of any Covered RSUs in accordance with the applicable RSU’s terms, whether vesting is based on the passage of time or the achievement of performance goals, I will have compensation income equal to the fair market value of the shares of the Company’s common stock subject to the RSUs that are settled on such settlement date and that the Company is required to withhold income and employment taxes in respect of that compensation income.

I desire to establish a plan and process to satisfy such withholding obligation in respect of all Covered RSUs through an automatic sale of the number of shares of the Company’s common stock that would otherwise be issuable to me on each applicable settlement date in an amount sufficient to satisfy the applicable withholding obligation, with the proceeds of the sale delivered to the Company in satisfaction of the applicable withholding obligation.

I understand that the Company has arranged for the administration and execution of its equity incentive programs and the sale of securities by participants thereunder pursuant to a platform administered by a third party (the “Administrator”) and the Administrator’s designated brokerage partner.

Upon the settlement of any of my Covered RSUs after the 30th day following the Adoption Date or such longer period as required by the Company’s insider trading policy or otherwise (the “Cooling-Off Period”), I hereby appoint the Administrator (or any successor administrator) to automatically sell such number of shares of the Company’s common stock issuable with respect to such RSUs that vested and settled as is sufficient to generate net proceeds sufficient to satisfy the Company’s minimum statutory withholding obligations with respect to the income recognized by me in connection with the vesting and settlement of such RSUs (based on minimum statutory withholding rates for all tax purposes, including payroll and social security taxes, that are applicable to such income), and the Company shall receive such net proceeds in satisfaction of such tax withholding obligation.

I hereby appoint the Chief Executive Officer, the Chief Financial Officer and the Senior Vice President, General Counsel, and any of them acting alone and with full power of substitution, to serve as my attorneys-in-fact to arrange for the sale of shares of the Company’s common stock in accordance with this Instruction. I agree to execute and deliver such documents, instruments and certificates as may reasonably be required in connection with the sale of the shares of common stock pursuant to this Instruction.

I hereby agree and acknowledge that this Instruction shall automatically terminate and be of no further force and effect if I am appointed to the Company’s Leadership Team by the Board of Directors of the Company, effective upon the date of any such appointment or such later date as may be required under the rules and regulations promulgated by the Securities and Exchange Commission and under the Company’s policies and procedures including its insider trading policy.

I hereby certify that, as of the Adoption Date:

(i) I am not prohibited from entering into this Instruction by the Company’s insider trading policy or otherwise;

(ii) I am not aware of any material nonpublic information about the Company or its common stock; and

(iii) I am adopting this Instruction in good faith and not as part of a plan or scheme to evade the prohibitions of Rule 10b-5 under the Exchange Act.

________________________________

Print Name: _____________________

Date: __________________________

Covered RSUs:

The following restricted stock units (“RSUs”) are covered by this Instruction.