Form 8-K

8-K — Gain Therapeutics, Inc.

Accession: 0001104659-26-078848

Filed: 2026-06-29

Period: 2026-06-29

CIK: 0001819411

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Other Events

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM

8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):

June 29, 2026

Gain Therapeutics, Inc.

(Exact name of registrant as specified in its charter)

Delaware

001-40237

85-1726410

(State or Other Jurisdiction

of Incorporation)

(Commission File

Number)

(I.R.S. Employer

Identification No.)

4800 Montgomery Lane, Suite 220

Bethesda, Maryland 20814

(Address of principal executive offices, including zip code)

(301)

500-1556

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since

last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under

any of the following provisions:

¨ Written

communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting

material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement

communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement

communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant

to Section 12(b) of the Act:

Title

of Each Class:

Trading

Symbol

Name

of Each Exchange on which Registered

Common Stock, par value $0.0001 per share

GANX

The

Nasdaq Stock

Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR§230.405)

or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2).

Emerging growth company x

If an emerging growth company,

indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised

financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 8.01. Other Events.

On June 29, 2026, Gain Therapeutics, Inc. (the

“Company”) announced that the U.S. Food and Drug Administration (“FDA”) has authorized the Company’s Investigational

New Drug application for GT-02287. FDA’s decision will allow initiation of the Company’s Phase 2 clinical development of GT-02287

in Parkinson’s disease with or without a GBA1 mutation in the U.S. Both the Phase 1a and Phase 1b studies of GT-02287 were conducted

in Australia. The sites in Australia are expected to also participate in the Phase 2 study along with new sites in the U.S. and select

European centers. The initiation of the Phase 2 study of GT-02287 is anticipated to occur during the third quarter of 2026.

The planned Phase 2a study of oral GT-02287

in treated and untreated participants with early Parkinson’s disease is expected to enroll participants across sites in the

United States, Australia, and Europe. The Company expects initiation of the Phase 2a in the third quarter of 2026.

Cautionary Note Regarding Forward-Looking Statements

This Current Report on Form 8-K 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. Such forward-looking statements include, but are not limited to, statements regarding: the development of the Company’s

current or future product candidates; expectations regarding the completion and timing of results from a Phase 1b clinical study for GT-02287,

including any extension studies; the timing of the commencement of the Phase 2 clinical study for GT-02287; the ability for the Company

to enroll patients in its planned Phase 2 clinical study for GT-02287; the Company’s ability to replicate positive results from

earlier preclinical studies or clinical trials in current or future clinical trials; and the potential therapeutic and clinical benefits

of the Company’s product candidates, including. 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, 2025, and other filings made with the SEC. 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. The Company has no obligation, and expressly disclaims

any obligation, to update, revise or correct any of the forward-looking statements, whether because of new information, future events

or otherwise.

Signature

Pursuant to the requirements

of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto

duly authorized.

GAIN THERAPEUTICS, INC.

Dated: June 29, 2026

By:

/s/ Gene Mack

Gene Mack

Chief Executive Officer

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