Diamyd Medical AB: Diamyd Medical receives Notice of Grant in Japan for insulin-based antigen therapy patent in type 1 diabetes

Diamyd Medical has received a Notice of Grant in Japan for a patent covering the use of insulin-based antigens to treat individuals with type 1 diabetes who carry the HLA DR4-DQ8 genetic marker. Once issued, the patent is expected to remain in force until 2038.

Diamyd Medical holds granted precision medicine patents for treating and preventing type 1 diabetes in key global markets:

• The newly granted Japanese patent for insulin-based antigen therapy targeting individuals with HLA DR4-DQ8 has corresponding patents granted in Europe, Eurasia, Hong Kong, and South Korea, with additional applications pending in other territories.
• Patents covering the treatment and prevention of type 1 diabetes in individuals carrying HLA DR3-DQ2 using retogatein (rhGAD65) have been granted in Europe, Eurasia, Hong Kong, Israel, Japan, South Africa, and South Korea. These protections extend through 2038, with further applications under review in additional markets.

Together, the HLA DR3-DQ2 and HLA DR4-DQ8 genetic markers are present in up to 90% of individuals with type 1 diabetes, highlighting the broad clinical relevance of these targeted therapies.

About Diamyd Medical
Diamyd Medical develops precision medicine therapies to prevent and treat type 1 diabetes. Retogatein (rhGAD65) formulated with alum is an investigational antigen-specific immunotherapy, designed to induce antigen-specific immune tolerance to GAD65 and preserve endogenous insulin production in individuals with type 1 diabetes who carry the HLA DR3-DQ2 gene. Retogatein has been granted Orphan Drug Designation in the U.S. as well as Fast Track Designation by the U.S. FDA for the treatment of Stage 3 (clinically diagnosed symptomatic) type 1 diabetes. Fast Track Designation has also been granted for the treatment of Stage 1 and 2 (pre-symptomatic) type 1 diabetes. DIAGNODE-3, a confirmatory Phase 3 trial with potential for an accelerated approval pathway in the US, is being conducted at 57 clinics in eight European countries and in the US in patients with recent-onset (Stage 3) type 1 diabetes. Significant results in preserving endogenous insulin production have previously been shown in a large genetically predefined patient group - both in a large-scale meta-analysis as well as in the Company's prospective European Phase 2b trial. The DIAGNODE-3 trial has only included patients from this specific patient group that carries the common genotype known as HLA DR3-DQ2, which constitutes approximately 40 % of patients with type 1 diabetes in Europe and the US. A biomanufacturing facility is under development in Umeå, Sweden, for the manufacture of retogatein (recombinant GAD65 protein), the active ingredient in the antigen-specific immunotherapy. Diamyd Medical is a major shareholder in the stem cell company NextCell Pharma AB and in the artificial intelligence company MainlyAI AB.

Diamyd Medical's B share is traded on Nasdaq First North Growth Market under the ticker DMYD B. FNCA Sweden AB is the Company's Certified Adviser.

For further information, please contact:
Ulf Hannelius, President and CEO
Phone: [phone]
E-mail: [e-mail]

Diamyd Medical AB (publ)
Box 7349, SE-103 90 Stockholm, Sweden. Phone: [phone], Fax: [phone]
E-mail: [e-mail] Reg. no.: 556242-3797 Website: https://www.diamyd.com

This information is information that Diamyd Medical is obliged to make public pursuant to the EU Market Abuse Regulation. The information was provided by the contact person above, for publication on 14.05 CET, March 19, 2026.