Company: GANX
Filing Date: 2025-07-15
Form Type: 424B5
Source: 0001104659-25-068103
Chunk: 9

Company: Gain Therapeutics, Inc.
Filing Date: 2025-07-15
Form: 424B5
Chunk 9
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2024, we received approval in Australia to initiate a Phase 1b trial for GT-02287 in people with Parkinson’s disease with or without the GBA1 mutation. We are working with local Parkinson’s disease (PD) advocacy groups in Australia to support enrollment and expect enrollment to complete in the summer of 2025 with interim data from the study expected by mid-2025. The Phase 1b open-label trial will assess the safety and tolerability of 13.5 mg/kg/day of GT-02287 for three months in patients with GBA1-PD or idiopathic Parkinson’s disease. Secondary endpoints include pharmacokinetics, GCase modulation, levels of GCase substrates, and other biomarkers in plasma and cerebrospinal fluid. The primary goal of the

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Phase 1b trial is to assess the safety and tolerability of GT-02287. Upon successful completion we expect to begin planning a Phase 2 study during the second half of 2025.

In preparation for the treatment of Parkinson’s disease patients, we initiated a chronic (6 months in rodents and 9 months in non-rodents) preclinical toxicity study in July 2024, enabling the conduct of clinical studies in patients with a GT-02287 treatment duration beyond three months. The 6- and 9-month studies will be completed in the second quarter of 2025 and the third quarter of 2025, respectively.

On June 30, 2025, we announced an update on the progress of the ongoing Phase 1b clinical study evaluating the safety and tolerability of GT-02287 in people with Parkinson’s Disease with or without a GBA1 mutation. The study, which aimed to enroll 15-20 participants, reached 16 participants on June 30, 2025, despite a two-month delay in protocol implementation. In addition, the independent data monitoring committee met recently and recommended to continue the study with no changes in dose level, concluding no serious treatment emergent adverse events have occurred. The faster-than-anticipated enrollment means all those participants will reach their 90-day visit in time to facilitate biomarker analysis of all CSF samples taken by fourth quarter of 2025 instead of the first quarter of 2026. Based on the greater relevance of CSF biomarkers as proof of drug activity, and considering the new timeline, we expect to provide full results on 90-day biomarker evidence