Atamyo Therapeutics Presents Promising Results in the First Patients Treated With Its ATA-200 Gene Therapy in the Clinical Trial Targeting LGMD-R5 Limb-Girdle Muscular Dystrophy

Atamyo Therapeutics announced at the American Society of Gene and Cell Therapy Annual Meeting 2026 the first safety, pharmacodynamics and efficacy results for its ATA-200 gene therapy in LGMD-R5 limb-girdle muscular dystrophy. The company said four patients have received the therapy as part of an ongoing Phase 1b/2 trial at the Powell Gene Therapy Center at the University of Florida. Dr. Barry Byrne is the principal investigator. Twelve-month follow-up data for the first two patients demonstrate the safety of the product and promising efficacy results. At a dose of 1.0E+14 vg/kg, the company said more than 90% of muscle fibers expressed the SGCG gene, a significant and sustained reduction in CPK levels was observed, and clinical benefits were seen at 12 months post-treatment. CEO Angela Columbano said the initial results are very encouraging and demonstrate the potential of the product with biological data rarely seen in neuromuscular diseases at such an early stage. Further results from the ongoing study are expected in the coming months.