PTC Therapeutics has acquired Sangamo Therapeutics' BLA-stage Fabry disease gene therapy isaralgagene civaparvovec (ST-920) for up to USD 211 million, while Eli Lilly is taking control of Sangamo's genetic medicine platforms and prion disease program ST-506 in a separate USD 50 million deal.
The transactions emerged from a court-supervised auction of Sangamo's assets, with PTC prevailing over Astellas Pharma for ST-920. PTC will pay USD 111 million in cash at closing, plus USD 80 million if the therapy receives US FDA accelerated approval and another USD 20 million upon traditional approval. Lilly will acquire Sangamo's capsid delivery, zinc finger and modular integrase (MINT) platforms alongside ST-506 for USD 50 million.
ST-920 is an AAV-based gene therapy designed to deliver a functional copy of the GLA gene to liver cells, enabling sustained production of alpha-galactosidase A, the enzyme deficient in Fabry disease. The approach is intended to provide a one-time treatment capable of addressing the underlying enzyme deficiency and potentially reducing or eliminating the need for chronic enzyme replacement therapy.
The asset is already moving through US regulatory review. Sangamo began a rolling BLA submission under the accelerated approval pathway following the Phase I/II STAAR study, with preclinical and clinical modules submitted before its bankruptcy filing. The US FDA agreed that estimated glomerular filtration rate slope at 52 weeks could serve as an intermediate clinical endpoint for accelerated approval, with two-year eGFR data providing confirmatory evidence for traditional approval. The registrational dataset includes 32 dosed patients.
For Lilly, the transaction provides outright ownership of technologies aimed at some of the central challenges in genetic medicine, particularly delivery into the central nervous system. Sangamo's STAC-BBB capsid platform is engineered to transport AAV gene therapies across the blood-brain barrier, while its zinc finger technology enables targeted regulation or editing of genes and the MINT platform is designed for site-specific integration of large DNA sequences.
Lilly was already familiar with the delivery technology, having licensed the STAC-BBB capsid in April 2025 for up to five CNS targets. Acquiring the platform outright gives Lilly control of the technology and removes future milestone and royalty obligations as it expands its genetic medicines pipeline.