Company: GANX
Filing Date: 2025-11-28
Form Type: 424B5
Source: 0001104659-25-116944
Chunk: 20

Company: Gain Therapeutics, Inc.
Filing Date: 2025-11-28
Form: 424B5
Chunk 20
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 in an escrow, trust or similar arrangement. Oppenheimer will use its commercially reasonable efforts consistent with its normal trading and sales practices, to solicit offers to purchase the shares of common stock under the terms and subject to the conditions set forth in the Distribution Agreement. In connection with the sale of the common stock on our behalf, Oppenheimer will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of Oppenheimer will be deemed to be underwriting commissions or discounts. We have agreed to provide indemnification and contribution to Oppenheimer against certain civil liabilities, including liabilities under the Securities Act and the Exchange Act.

The offering of our common stock pursuant to the Distribution Agreement will terminate as permitted therein. We and Oppenheimer may each terminate the Distribution Agreement at any time upon ten days’ prior notice.

Oppenheimer and its affiliates may in the future provide various investment banking, commercial banking and other financial services for us and our affiliates, for which services they may in the future receive customary fees. To the extent required by Regulation M, Oppenheimer will not engage in any market making activities involving our common stock while the offering is ongoing under this prospectus supplement. We have filed a copy of the Distribution Agreement with the SEC as an exhibit to the Current Report on Form 8-K filed on September 6, 2024.

This prospectus supplement in electronic format may be made available on a website maintained by Oppenheimer, and Oppenheimer may distribute this prospectus supplement electronically.

Our common stock is listed on Nasdaq under the trading symbol “GANX.”

The transfer agent for our common stock to be issued in this offering is Pacific Stock Transfer Company, 6725 Via Austi Pkwy, Suite 300, Las Vegas, NV 89119.

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TABLE OF CONTENTS

### LEGAL MATTERS
Lowenstein Sandler LLP, New York, New York, will pass upon the validity of the issuance of the shares being sold in this offering. Oppenheimer & Co. Inc. is being represented in connection with this offering by Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., New York.

### EXPERTS
The consolidated financial statements of Gain Therapeutics, Inc. appearing in Gain Therapeutics, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2024have been audited by Ernst & Young AG,