FDA Speeds Up Trial for Novel Type 1 Diabetes Immunotherapy

STOCKHOLM, SWEDEN – December 29, 2025 – In a significant development for the type 1 diabetes community, Diamyd Medical announced it has received alignment from the U.S. Food and Drug Administration (FDA) to accelerate the timeline for its pivotal Phase 3 trial. The decision will allow the primary efficacy data for its investigational drug, Diamyd®, to be read out nine months earlier than planned, potentially speeding the arrival of a first-of-its-kind precision therapy for a genetically-defined subset of patients.

The Swedish biotech company confirmed that following recent discussions with the agency, the primary endpoint for the DIAGNODE-3 trial will now be assessed at 15 months post-treatment instead of the original 24 months. This change shortens the path to a full data readout, a critical step toward a potential Biologics License Application (BLA).

"We are very pleased with the FDA's feedback as it provides a clear way forward," said Ulf Hannelius, CEO of Diamyd Medical, in a statement. "The proposed change meaningfully shortens the timeline to the full primary efficacy readout in our registrational Phase 3 trial, while maintaining a robust assessment of long-term efficacy."

Navigating the Regulatory Gauntlet

The FDA's decision is more than a simple schedule change; it represents a major validation of Diamyd Medical's clinical strategy and the regulatory framework designed to bring promising drugs for serious conditions to patients faster. The company's therapy has already received multiple designations from the FDA, including Fast Track status for stages 1-3 of type 1 diabetes and Orphan Drug Designation for stage 3.

Fast Track is intended to facilitate the development of drugs that treat serious conditions and fill an unmet medical need, offering more frequent communication with the FDA and eligibility for accelerated approval. The Accelerated Approval pathway itself is a critical component of this strategy. It allows for earlier drug approval based on a surrogate endpoint—a marker believed to predict a clinical benefit—rather than waiting for long-term outcomes. For Diamyd®, the key surrogate endpoint is C-peptide, a biomarker that measures the body's own endogenous insulin production.

The FDA's acceptance of C-peptide preservation at 15 months as a primary endpoint is a landmark step. Preserving even small amounts of natural insulin production can lead to significant clinical benefits for patients, including better blood sugar control, reduced reliance on external insulin, and a lower risk of severe hypoglycemia. This regulatory stance builds on precedent, most notably the 2022 approval of Tzield (teplizumab), the first drug to delay the onset of stage 3 type 1 diabetes, which also used C-peptide data as part of its evidence package.

While the primary analysis is now set for 15 months, the original 24-month assessment will be retained as a key secondary endpoint. This will provide crucial data on the durability of the treatment effect, a key consideration for both regulators and clinicians.

Precision Medicine Takes Aim at Diabetes

Diamyd® is not a one-size-fits-all treatment. It is an antigen-specific immunotherapy at the forefront of precision medicine, designed specifically for individuals with a particular genetic makeup. The DIAGNODE-3 trial is exclusively enrolling approximately 300 individuals recently diagnosed with type 1 diabetes who carry the HLA DR3-DQ2 genotype.

This specific genetic profile is present in approximately 40% of people with type 1 diabetes in Europe and the United States and is strongly associated with the autoimmune response that destroys insulin-producing beta cells in the pancreas. Unlike traditional treatments that focus on replacing lost insulin, Diamyd® aims to intervene directly in the disease process. It works by introducing a specific antigen (the GAD65 protein) to re-educate the immune system, teaching it to tolerate the body's own beta cells rather than attack them.

This targeted approach is based on prior research, including a large-scale meta-analysis and a European Phase 2b trial, which showed significant efficacy in preserving insulin production specifically within this genetically defined patient group. By focusing the Phase 3 trial on the population most likely to respond, Diamyd Medical increases the probability of demonstrating a clear clinical benefit and offers a tailored solution that addresses the root cause of the disease for a substantial portion of the patient population.

The Competitive and Financial Horizon

The accelerated timeline has significant implications for Diamyd Medical's position in the competitive landscape and its appeal to investors. While Tzield broke new ground as a disease-modifying therapy, it is a broad immunomodulator. Diamyd®'s highly specific, antigen-based approach represents a different and potentially complementary strategy in the fight against type 1 diabetes.

For a clinical-stage biotech company, time is a critical resource. Shortening the pivotal trial by nine months significantly de-risks the development pathway and brings the potential for market entry and revenue generation much closer. This news is likely to be viewed favorably by investors, as it enhances the company's valuation and makes it a more attractive candidate for potential partnerships with larger pharmaceutical firms looking to bolster their diabetes portfolios.

The next major catalyst for the company remains the previously scheduled interim efficacy analysis of the DIAGNODE-3 trial. This readout, expected by the end of March 2026, will involve data from approximately 170 participants at the 15-month mark. According to the company, positive results from this interim look could be sufficient to support an accelerated BLA submission, potentially bringing the therapy to patients even sooner.

As the trial continues to recruit patients across 57 clinics in Europe and the U.S., the diabetes community watches with keen interest. The alignment with the FDA not only accelerates a single trial but also reinforces a pathway for innovative, targeted therapies that could one day change the definition of living with type 1 diabetes from a life of management to one of modification and preservation.