BioMarin Pharmaceutical has signed an exclusive worldwide licence agreement with GC Biopharma and Hanmi Pharm of South Korea for HM15421/GC1134A, an investigational long acting enzyme replacement therapy for Fabry disease. BioMarin will pay 70 million dollars upfront. The two Korean companies are jointly eligible for up to a further 405 million dollars in development and commercial milestone payments, plus tiered royalties on net sales, taking the combined upfront and milestone consideration to 475 million dollars before royalties.
The candidate is a recombinant human alpha galactosidase A enzyme in a Phase 1/2 open label, dose ranging proof of concept trial in adults with Fabry disease, registered as NCT06858397. It received United States orphan drug designation in 2024. BioMarin says the design, built for extended half life and subcutaneous dosing, has the potential to make it the first subcutaneous enzyme replacement therapy for Fabry disease. That is a company claim about an unapproved product, and the differentiated efficacy the company cites comes from preclinical studies, not from clinical results.
Under the agreement, BioMarin takes sole responsibility for later development, manufacturing and commercialisation outside South Korea once the ongoing Phase 1/2 study completes. GC Biopharma and Hanmi retain commercialisation rights in South Korea.
Fabry disease is a lysosomal storage disorder in which a fatty substance builds up in cells and blood vessels. For BioMarin, a rare disease specialist, the deal adds a second potential Fabry treatment alongside the franchise it gained through this years Amicus acquisition, and it does so at an early stage price: 70 million dollars committed now, with the remaining 405 million dollars payable only if development and commercial milestones are met.