BioMarin Signs $475M Licensing Deal for Investigational Fabry Disease Therapy

BioMarin Pharmaceutical Inc. (BMRN) announced an exclusive worldwide licensing agreement with GC Biopharma Corp. (006280.KS) and Hanmi Pharm Co., Ltd. (128940.KS) to develop and commercialize HM15421/GC1134A, an investigational long-acting enzyme replacement therapy for Fabry disease, excluding South Korea. BioMarin will pay $70 million upfront, with GC Biopharma and Hanmi jointly eligible for up to $405 million in development and commercial milestone payments plus tiered royalties on net sales. The candidate, a recombinant alpha-galactosidase A enzyme therapy in Phase 1/2 trials, is designed to extend half-life and improve stability, potentially enabling subcutaneous administration—which could make it the first subcutaneous enzyme replacement treatment for Fabry disease. It received FDA Orphan Drug Designation in 2024. BioMarin will assume subsequent clinical development, manufacturing and commercialization outside South Korea following the Phase 1/2 study. The deal expands BioMarin's Fabry portfolio after its acquisition of Amicus earlier in 2026. BMRN traded at $56.78, up 1.39%.