Gain Therapeutics Presents Initial Data from Phase 1b Clinical Study of GT-02287 in Parkinson’s Patients at International Congress of Parkinson’s Disease and Movement Disorders® 

Rhea-AI Summary

Gain Therapeutics (NASDAQ: GANX) presented interim Phase 1b data for GT-02287 in Parkinson’s disease on October 6, 2025. Early dosing produced stability and trending improvements in MDS‑UPDRS Parts II and III by Day 90 in several participants while Part I remained unchanged.

GT-02287 was generally well tolerated with no treatment‑emergent serious adverse events, a consistent plasma PK profile within the projected therapeutic range, and DMC recommendations to continue the study. Australian authorities approved a study extension allowing treatment up to 12 months. A virtual KOL webinar is scheduled for October 14, 2025.

Positive

• No treatment‑emergent serious adverse events reported
• Plasma PK within projected therapeutic range across sampled patients
• DMC recommended continuation after two independent reviews
• Australian approval to extend Phase 1b treatment up to 12 months
• Mean MDS‑UPDRS Parts II and III improved by Day 90 in several participants

Negative

• Transient alkaline phosphatase and liver enzyme increases observed in some participants
• Early efficacy signals limited to initial nine participants with 90‑day data

Insights

Clinical Development Strategist

Early Phase 1b safety and exploratory efficacy signals are promising but limited by small sample and interim status.

GT-02287 showed tolerability with no treatment-emergent serious adverse events and plasma exposures in patients matched projected therapeutic ranges and prior healthy-volunteer data, which supports continued dosing and collection of PK/safety data.

The reported mean improvements in MDS-UPDRS Parts II and III at Day 90 were observed in several participants but were not present at Day 30; this finding is preliminary given the small number of participants (first 9 observed improvements) and the interim nature of the dataset. Transient liver enzyme elevations were noted and normalized despite ongoing dosing; two independent DMC reviews recommended continuation and Australian authorities approved treatment extension to up to 12 months.

Watch for complete data from the full cohort at the end of the 90-day follow-up, formal statistical analyses of MDS-UPDRS changes, detailed safety tables including liver enzyme time courses, and longer-term outcomes from the approved up-to-12-month extension. The October 14, 2025 KOL webinar will provide additional context.

Improvement observed in MDS-UPDRS scores in first 9 participants enrolled; 90-day follow-up continuing in remaining participants

Plasma exposures in patients within projected therapeutic range and comparable to exposures observed in Phase 1 healthy volunteer study

GT-02287 was generally well-tolerated with no treatment emergent serious adverse events (TESAEs); no changes recommended from two independent DMC reviews

Gain to host GT-02287 KOL event on October 14^th at 4 p.m. EST

BETHESDA, Md., Oct. 06, 2025 (GLOBE NEWSWIRE) -- Gain Therapeutics, Inc. (Nasdaq: GANX) (“Gain”, or the “Company”), a clinical-stage biotechnology company leading the discovery and development of the next generation of allosteric small molecule therapies, today presented a poster at the International Congress of Parkinson’s Disease and Movement Disorders^® summarizing early safety and tolerability findings, the primary endpoint, and observations from key exploratory endpoints from the Phase 1b clinical study of GT-02287 in people with Parkinson’s disease (PD) with or without a GBA1 mutation.

“We are pleased to be able to present encouraging early takeaways from our Phase 1b study,” said Gene Mack, President and Chief Executive Officer of Gain Therapeutics. “The stability and trending improvements we have observed in MDS-UPDRS scores was not something we were expecting to see with 90 days of dosing. We look forward to further contextualizing our observations in an upcoming webinar.”

The poster, titled, “GT-02287 in Parkinson’s Disease: Interim data from a Phase 1b study,” was presented on-site by Chief Medical Officer Jonas Hannestad, M.D., Ph.D. GT-02287 was generally well tolerated, with no treatment-emergent serious adverse events observed. A transient increase in alkaline phosphatase and other liver enzymes has been observed in some participants and normalized despite ongoing dosing. At two different meetings, the data monitoring committee (DMC) has recommended continuation of the study and more recently, Australian health authorities have approved the Phase 1b study extension for patients who can now be treated for up to 12 months.

Of the 21 participants, two are treatment-naïve, two are on deep brain stimulation, and 18 are on levodopa and/or dopamine agonists or other PD drugs.

Mean MDS-UPDRS scores at baseline were 5.8, 7.4, and 24.7 for Parts I, II, and III, respectively. Importantly, several participants experienced an improvement in their UPDRS Part II and III scores after 90 days of dosing with GT-02287 while mean Part I scores remained unchanged. The mean improvement in Parts II and III by Day 90, which was not observed by Day 30, suggests that GT-02287 has a disease-slowing effect, consistent with the preclinical models in vivo and the proposed mechanism of action of GT-02287, supporting continued development.

The plasma pharmacokinetics (PK) profile was consistent across all 14 participants sampled, was within the projected therapeutics range, and comparable to exposures observed in healthy volunteers in the Phase 1 study.

A PDF of the poster presented at the International Congress of Parkinson’s Disease and Movement Disorders is available on the Science and Technology section of the Company’s website at https://gaintherapeutics.com/science-and-technology/posters.

Upcoming Virtual KOL Event Registration

Gain Therapeutics will host a webinar on Tuesday, October 14 at 4:00pm ET to review results presented at the International Congress of Parkinson’s Disease and Movement Disorders. Further details about the event will be issued at a later date in a separate press release. To register, please click here: https://lifescievents.com/event/gst492thwp/ 

About GT-02287
Gain Therapeutics’ lead drug candidate, GT-02287, is in clinical development for the treatment of Parkinson’s disease (PD) with or without a GBA1 mutation. The orally administered, brain-penetrant small molecule is an allosteric enzyme modulator that restores the function of the lysosomal enzyme glucocerebrosidase (GCase) which becomes misfolded and impaired due to mutations in the GBA1 gene, the most common genetic abnormality associated with PD, or other age-related stress factors. In preclinical models of PD, GT-02287 restored GCase enzymatic function, reduced ER stress, lysosomal and mitochondrial pathology, aggregated α-synuclein, neuroinflammation and neuronal death, as well as plasma neurofilament light chain (NfL) levels, a biomarker of neurodegeneration. In rodent models of both GBA1-PD and idiopathic PD, GT-02287 was shown to rescue deficits in motor function and gait and prevent the development of deficits in complex behaviors such as nesting.

Compelling preclinical data in models of both GBA1-PD and idiopathic PD, demonstrating a disease-modifying effect after administration of GT-02287, suggest that GT-02287 may have the potential to slow or stop the progression of Parkinson’s disease.

Results from a Phase 1 study of GT-02287 in healthy volunteers demonstrated favorable safety and tolerability, plasma and CNS exposures in the projected therapeutic range, and target engagement with a >50% increase in glucocerebrosidase (GCase) activity among those receiving GT-02287 at clinically relevant doses.

GT-02287 is currently being evaluated in a Phase 1b clinical trial for the treatment of Parkinson’s disease with or without a GBA1 mutation. The primary endpoint of the trial, which enrolled participants across 7 sites in Australia, is to evaluate the safety and tolerability of GT-02287 after 3 months of dosing in people with Parkinson’s disease.

Gain’s lead program in Parkinson’s disease has been awarded funding support early in its development from The Michael J. Fox Foundation for Parkinson’s Research (MJFF) and The Silverstein Foundation for Parkinson’s with GBA, as well as from the Eurostars-2 joint program with co-funding from the European Union Horizon 2020 research and Innosuisse – Swiss Innovation Agency.

About Gain Therapeutics, Inc.
Gain Therapeutics, Inc. is a clinical-stage biotechnology company leading the discovery and development of next generation allosteric therapies. Gain’s lead drug candidate, GT-02287 is currently being evaluated for the treatment of Parkinson’s disease with or without a GBA1 mutation in a Phase 1b clinical trial. GT-02287 has further potential in Gaucher’s disease, dementia with Lewy bodies, and Alzheimer’s disease. Gain has multiple undisclosed preclinical assets targeting lysosomal storage disorders, metabolic diseases, and solid tumors.

Gain’s unique approach enables the discovery of novel, allosteric small molecule modulators that can restore or disrupt protein function. Deploying its highly advanced Magellan™ platform, Gain is accelerating drug discovery and unlocking novel disease-modifying treatments for untreatable or difficult-to-treat disorders including neurodegenerative diseases, rare genetic disorders and oncology.

Forward-Looking Statements
This release contains “forward-looking statements” made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. These statements are typically preceded by words such as “believes,” “expects,” “anticipates,” “intends,” “will,” “may,” “should,” or similar expressions. These forward-looking statements reflect management’s current knowledge, assumptions, judgment and expectations regarding future performance or events. Although management believes that the expectations reflected in such statements are reasonable, they give no assurance that such expectations will prove to be correct or that those goals will be achieved, and you should be aware that actual results could differ materially from those contained in the forward-looking statements. Forward-looking statements are subject to a number of risks and uncertainties, including, but not limited to, statements regarding: the development of the Company’s current or future product candidates including GT-02287; expectations regarding the completion, quality and timing of results from a Phase 1b clinical study for GT-02287; expectations regarding the timing of patient enrollment for a Phase 1b clinical study for GT-02287, including the dose extension study; the timing of any submissions to the FDA or other regulatory bodies and agencies; and the potential therapeutic and clinical benefits of the Company’s product candidates. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the Company’s business in general, please refer to the Company’s Form 10-K for the year ended December 31, 2024. All forward-looking statements are expressly qualified in their entirety by this cautionary notice. You are cautioned not to place undue reliance on any forward-looking statements, which speak only as of the date of this release. We have no obligation, and expressly disclaim any obligation, to update, revise or correct any of the forward-looking statements, whether because of new information, future events or otherwise.

Investors:
Gain Therapeutics, Inc. 
Apaar Jammu 
Manager, Investor Relations and Public Relations
ajammu@gaintherapeutics.com

LifeSci Advisors LLC
Chuck Padala
Managing Director
chuck@lifesciadvisors.com

Media:
Russo Partners LLC
Nic Johnson and Elio Ambrosio
nic.johnson@russopartnersllc.com
elio.ambrosio@russopartnersllc.com
(760) 846-9256

FAQ

What interim results did Gain Therapeutics report for GT-02287 (GANX) on October 6, 2025?

Gain reported trending improvements in MDS‑UPDRS Parts II and III by Day 90 in several participants and no treatment‑emergent serious adverse events.

How many participants have shown improvement in the Phase 1b GT-02287 study (GANX)?

Improvements were observed in the first nine participants with 90‑day data; the full 21‑participant cohort remains under follow‑up.

Were there any safety concerns reported for GT-02287 in the October 6, 2025 update?

No treatment‑emergent serious adverse events were reported, though some participants had transient increases in alkaline phosphatase and other liver enzymes.

What did the data monitoring committee decide about the GT-02287 Phase 1b study (GANX)?

Two independent DMC reviews recommended continuation of the study without changes.

Did regulators allow longer GT-02287 treatment in the Phase 1b study (GANX)?

Yes; Australian health authorities approved a study extension permitting treatment up to 12 months.

How did GT-02287 plasma levels compare to prior studies in the October 6, 2025 update?

Plasma pharmacokinetics were consistent across sampled patients and comparable to exposures seen in the Phase 1 healthy volunteer study.

When is Gain Therapeutics hosting a webinar to discuss the GT-02287 results (GANX)?

A virtual KOL webinar is scheduled for October 14, 2025 at 4:00 PM ET.