This Amendment No. 3 (this Amendment) amends and supplements the
Solicitation/Recommendation Statement on Schedule 14D-9 (as amended or supplemented from time to time, the Schedule 14D-9) previously filed by Sage
Therapeutics, Inc., a Delaware corporation (Sage or Company), with the Securities and Exchange Commission on July 2, 2025, relating to the tender offer by Supernus Pharmaceuticals, Inc., a Delaware corporation
(Supernus or Parent), and Saphire, Inc., a Delaware corporation and a wholly owned subsidiary of Supernus (Purchaser), to purchase all of the outstanding shares of common stock of Sage, par value $0.0001 per share
(the Shares), for (i) $8.50 per Share, net to the seller in cash, without interest and subject to any withholding of taxes, plus (ii) one contingent value right per Share (a CVR), which represents the right to
receive up to $3.50 per Share upon the satisfaction of specified milestones, net to the seller in cash, without interest and subject to any withholding of taxes, pursuant to the CVR Agreement (as defined in the Agreement and Plan of Merger, dated
June 13, 2025, by and among Supernus, Purchaser and Sage (the Merger Agreement)), upon the terms and subject to the conditions set forth in the Offer to Purchase, dated July 2, 2025 (as may be amended or supplemented from time
to time, the Offer to Purchase) and in the related Letter of Transmittal (as may be amended or supplemented from time to time, and together with the Offer to Purchase, the Offer), pursuant to the Merger Agreement.
Except to the extent specifically provided in this Amendment, the information set forth in the
Schedule 14D-9 remains unchanged. Capitalized terms used but not otherwise defined in this Amendment shall have the meanings ascribed to them in the
Schedule 14D-9. This Amendment is being filed to reflect certain updates as set forth below.
Item 8. Additional Information.
Item 8 of
the Schedule 14D-9 is hereby amended and supplemented as follows:
1. By adding the following
section after the last full paragraph on page 70 in the section captioned Cautionary Note Regarding Forward Looking Statements:
Expiration of Offering Period; Completion of Merger
At one minute past 11:59 p.m., Eastern Time, on July 30, 2025 (the Expiration Date), the Offer expired and
was not further extended. Equiniti Trust Company, LLC, in its capacity as the depositary for the Offer, advised Purchaser that, as of the Expiration Date, a total of 36,313,509 Shares were validly tendered (and not validly withdrawn) pursuant to the
Offer, representing approximately 58% of the total number of Shares outstanding at the time of the expiration of the Offer. The number of Shares tendered satisfied the Minimum Condition. As the Minimum Condition and each of the other conditions of
the Offer were satisfied, Purchaser irrevocably accepted for payment all the Shares validly tendered (and not validly withdrawn) pursuant to the Offer effective as of the Expiration Date, and will, as promptly as practicable thereafter, pay for such
Shares as required by the Merger Agreement.
Following the consummation of the Offer on July 31, 2025, Supernus
completed its acquisition of Sage, pursuant to the terms of the Merger Agreement, through the merger of Purchaser with and into Sage without a meeting of the Sage stockholders in accordance with Section 251(h) of the DGCL, with Sage continuing
as the Surviving Corporation and a wholly owned subsidiary of Supernus.
As a result of the Merger, the Shares will be
delisted from and will cease to trade on the Nasdaq Global Market and will be deregistered under the Exchange Act.
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