Company: SUPN
Filing Date: 2025-07-02
Form Type: SC TO-T
Source: 0001104659-25-065398
Chunk: 2

Company: SUPERNUS PHARMACEUTICALS, INC.
Filing Date: 2025-07-02
Form: SC TO-T
Chunk 2
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)(2) hereto, are incorporated herein by reference with respect to Items 4, 5, 6 and 11 of this Schedule TO.

Capitalized terms used and not defined herein shall have the meanings assigned to such terms in the Offer to Purchase.

## Item 1.   Summary Term Sheet.
The information set forth in the “Summary Term Sheet” of the Offer to Purchase is incorporated herein by reference.

## Item 2.   Subject Company Information.
(a) The name of the subject company and the issuer of the securities to which this Schedule TO relates is Sage Therapeutics, Inc., a Delaware corporation. Sage’s principal executive offices are located at 55 Cambridge Parkway, Cambridge, Massachusetts 02142. Sage’s telephone number is 617-299-8380.

(b) This Schedule TO relates to the outstanding Shares. Sage has advised Purchaser and Supernus that, as of the close of business on June 27, 2025 (the most recent practicable date), 62,631,252 Shares were issued and 62,628,219 Shares were outstanding.

(c) The information set forth in Section 6 (entitled “Price Range of Shares; Dividends on the Shares”) of the Offer to Purchase is incorporated herein by reference.

## Item 3.   Identity and Background of the Filing Person.
(a) – (c) This Schedule TO is filed by Purchaser and Supernus. The information set forth in Section 8 (entitled “Certain Information Concerning Supernus and Purchaser”) of the Offer to Purchase and Schedule I to the Offer to Purchase is incorporated herein by reference.

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## Item 4.   Terms of the Transaction.
(a)(1)(i) – (viii), (xii), (a)(2)(i) – (iv), (vii) The information set forth in the following sections of the Offer to Purchase is incorporated herein by reference:

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the “Summary Term Sheet”

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the “Introduction”

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Section 1 — “Terms of the Offer”

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Section 2 — “Acceptance for Payment and Payment for Shares”

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Section 3 — “Procedures for Accepting the Offer and Tendering Shares”

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Section 4 — “Withdrawal Rights”

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Section 5 — “Material U.S. Federal Income Tax Considerations”

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Section 11 — “The Merger Agreement; CVR Agreement”

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Section 12 — “Purpose of the Offer; Plans for