This Amendment No. 1 (this “Amendment”) amends and supplements the Tender
Offer Statement on Schedule TO filed by Sigma Merger Sub, Inc., a Delaware corporation (“Purchaser”) and a direct wholly owned subsidiary of Neurocrine Biosciences, Inc., a Delaware corporation (“Neurocrine”), and
Neurocrine with the U.S. Securities and Exchange Commission on April 20, 2026 (together with any subsequent amendments and supplements thereto, the “Schedule TO”). The Schedule TO relates to the offer by Purchaser to purchase
all of the outstanding shares of common stock, par value $0.001 per share (the “Shares”), of Soleno Therapeutics, Inc., a Delaware corporation (“Soleno”), in exchange for $53.00 per Share, payable in cash without interest and
subject to reduction for any applicable withholding taxes, upon the terms and conditions set forth in the offer to purchase, dated April 20, 2026 (the “Offer to Purchase”), filed as Exhibit (a)(1)(A) to the Schedule TO, and in the
related letter of transmittal (the “Letter of Transmittal”), filed as Exhibit (a)(1)(B) to the Schedule TO, which, as each may be amended or supplemented from time to time, collectively constitute the “Offer.”
Except as otherwise set forth in this Amendment, the information set forth in the Schedule TO remains unchanged and is incorporated herein by
reference to the extent relevant to the items in this Amendment. Capitalized terms used but not defined herein have the meanings ascribed to them in the Offer to Purchase.
Items 1 through 9, and Item 11.
The
Offer to Purchase and Items 1 through 9 and Item 11 of the Schedule TO, to the extent such items incorporate by reference the information contained in the Offer to Purchase, are hereby amended and supplemented as follows:
a) “The Tender Offer—Section 15—Conditions to the Offer” of the Offer to Purchase is amended by adding a new
paragraph at the end of such section to read as follows:
“The Regulatory Condition to the Offer, requiring that all
applicable waiting periods under the HSR Act and any required antitrust approvals shall have expired or been terminated (including any timing agreement entered into with any Governmental Authority) and any approvals or clearances required thereunder
shall have been obtained, has been satisfied. The Offer continues to be subject to the remaining Offer Conditions.”
b) “The
Tender Offer—Section 16—Certain Legal Matters; Regulatory Approvals” of the Offer to Purchase is amended by adding a new paragraph at the end of the subsection titled “Compliance with the HSR Act” to read as
follows:
“Pursuant to the Merger Agreement, on April 10, 2026, each of Neurocrine and Soleno filed a Premerger
Notification and Report Form under the HSR Act with respect to the Offer and the Merger with the Antitrust Division of the United States Department of Justice and the FTC. As of 11:59 p.m. Eastern Time, on April 27, 2026, the waiting period
under the HSR Act applicable to the Offer expired. Accordingly, the Regulatory Condition to the Offer, requiring that all applicable waiting periods under the HSR Act and any required antitrust approvals shall have expired or been terminated
(including any timing agreement entered into with any Governmental Authority) and any approvals or clearances required thereunder shall have been obtained, has been satisfied. The Offer continues to be subject to the remaining conditions set forth
in the Offer to Purchase. See Section 15—‘Conditions to the Offer.’”
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