EMA Grants Orphan Drug Designation To Dyne Therapeutics’ DYNE-251 For Duchenne Muscular Dystrophy

Dyne Therapeutics, Inc., a clinical-stage biotechnology company focused on developing life-changing therapies for individuals with genetically driven neuromuscular diseases, has announced that the European Commission (EC) has granted orphan drug designation to its investigational therapy, DYNE-251, for the treatment of Duchenne muscular dystrophy (DMD).

DYNE-251 is currently being studied in the Phase 1/2 DELIVER global clinical trial, which is enrolling individuals with DMD who are amenable to exon 51 skipping. The therapy has shown promising results in the ongoing trial, with long-term clinical data demonstrating unprecedented and sustained functional improvement at the selected registrational dose. These results were presented in March at the 2025 Muscular Dystrophy Association (MDA) Clinical & Scientific Conference. Among the key functional assessments being used in the trial is the Stride Velocity 95th Centile (SV95C), a digital outcome measure recognized as a primary endpoint in DMD clinical studies in Europe.

Doug Kerr, MD, PhD, chief medical officer of Dyne, stated, “Our recent long-term DELIVER trial results demonstrated clinically relevant and sustained functional improvement through 18 months, including as assessed by SV95C, which may support a strong rationale for regulatory approval in Europe. We are pleased that the EC has granted orphan drug designation to DYNE-251, reinforcing our belief that our next-generation exon 51 skipping investigational therapy for DMD may be able to bring clinically meaningful functional improvement to those living with this devastating disease. With full enrollment of the registrational expansion cohort in the DELIVER trial complete, we look forward to sharing data from this cohort in late 2025 and the potential to move forward with our first regulatory submissions in early 2026.”

The European Commission grants orphan drug designation to treatments intended for the diagnosis, prevention, or treatment of rare, serious, and life-threatening diseases that affect fewer than five in 10,000 people in the European Union. This designation offers several incentives to developers, including reduced regulatory fees, access to clinical protocol assistance, eligibility for research grants, and the potential for up to ten years of market exclusivity within the EU if the treatment is approved.

In addition to this latest recognition by the EC, DYNE-251 received orphan drug and rare pediatric disease designations from the U.S. Food and Drug Administration (FDA) in March 2023. These designations highlight the potential of DYNE-251 as an important therapeutic option for individuals living with DMD, a severe and progressive muscle-wasting disorder.