Regeneron’s garetosmab BLA for FOP accepted by FDA with Priority Review
Regeneron said the FDA accepted its garetosmab BLA for FOP and granted Priority Review, with a decision expected by August 2026. Phase 3 OPTIMA data reported major lesion reductions versus placebo.
Regeneron Pharmaceuticals announced that its Biologics License Application (BLA) for garetosmab, a treatment for fibrodysplasia ossificans progressiva (FOP), has been accepted by the U.S. Food and Drug Administration and granted Priority Review. The FDA’s decision is expected by August 2026. Garetosmab is a monoclonal antibody that targets an ultra-rare genetic disorder with no approved therapies.
The BLA submission is supported by Phase 3 OPTIMA trial data in adult patients. Reported results over 56 weeks included:
- A 90% to 94% reduction in new bone lesions versus placebo.
- A 99% reduction in the total volume of abnormal bone formation in a post-hoc analysis.
By neutralizing Activin A—a protein central to FOP’s bone growth—garetosmab addresses the root cause of the disease. FOP typically leads to severe mobility loss, and the article states a median survival age of 56 years.
Regeneron said it intends to initiate the OPTIMA 2 trial later in 2026 to evaluate safety and efficacy in pediatric and adolescent populations. The condition affects approximately 1,000 people in the U.S. and Europe.
On February 25, 2026, Regeneron closed with a 1.57% gain. The stock traded with a volume of $0.59 billion, ranking 207th in trading activity that day.