07:48 AM EDT, 09/17/2025 (MT Newswires) -- Regeneron Pharmaceuticals ( REGN ) said Wednesday its phase 3 study of garetosmab in adults with fibrodysplasia ossificans progressiva, or FOP, met its primary endpoint, demonstrating a greater reduction in new bone lesions compared with placebo.

The company said the trial enrolled 63 people with FOP aged at least 18 years old. The primary and key secondary endpoints were assessed at 56 weeks, with results indicating a reduction in total new lesion volume with garetosmab, Regeneron added.

Regeneron said it plans to complete the US regulatory submission for garetosmab in FOP by year-end, to be followed by global regulatory submissions in 2026. The company said it also expects to start a phase 3 trial of garetosmab in adolescents and children with FOP in 2026.

Regeneron shares were fractionally higher in premarket trading.