Company: GANX
Filing Date: 2025-07-15
Form Type: 424B5
Source: 0001104659-25-068103
Chunk: 7

Company: Gain Therapeutics, Inc.
Filing Date: 2025-07-15
Form: 424B5
Chunk 7
---
 with this offering. All forward-looking statements included in this prospectus and in the documents incorporated by reference in this prospectus are based on information available to us on the date of this prospectus or the date of the applicable document incorporated by reference. Except to the extent required by applicable laws or rules, we undertake no obligation to publicly update or revise any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future events or otherwise. All subsequent written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements contained above and throughout this prospectus and in the documents incorporated by reference in this prospectus. We qualify all of our forward-looking statements by these cautionary statements.

You should rely only on the information in this prospectus. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely upon it.

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TABLE OF CONTENTS

### PROSPECTUS SUPPLEMENT SUMMARY
This summary highlights information contained elsewhere or incorporated by reference in this prospectus supplement, the accompanying prospectus and in the documents we incorporate by reference. This summary does not contain all of the information that you should consider before deciding to invest in our common stock. You should read this entire prospectus supplement carefully, including the “Risk Factors” section contained in this prospectus supplement, the accompanying prospectus and in the documents we incorporate by reference.

### Overview
We are a biotechnology company developing novel small molecule therapeutics to treat diseases across several therapeutic areas, including, central nervous system (“CNS”) disorders, lysosomal storage disorders (“LSDs”), metabolic disorders, and other diseases that can be targeted through protein degradation, such as oncology.

GT-02287 — our lead product candidate, for the treatment of Parkinson’s disease, is currently being evaluated in a Phase 1b study in people with Parkinson’s disease with or without a GBA1 mutation.

We have generated an extensive preclinical data package providing evidence of the mechanism of action and safety of GT-02287. In preclinical models of GBA1 and idiopathic Parkinson’s disease, GT-02287 has been shown to restore glucocerebrosidase, or GCase, function in the lysosome, improve mitochondrial health, reduce toxic lipid substrates and toxic forms of alpha-synuclein, reduce neuroin