Core Viewpoint - Sangamo Therapeutics has received FDA acceptance for a rolling submission of the Biologics License Application (BLA) for isaralgagene civaparvovec (ST-920), a gene therapy for Fabry disease, indicating progress towards potential accelerated approval [1][4]. Company Developments - The FDA's acceptance follows a meeting in October 2025 where Sangamo discussed the efficacy and safety data for ST-920, with the FDA agreeing to use eGFR slope as a primary endpoint for accelerated approval [2][3]. - Sangamo plans to initiate the rolling submission of the BLA later in the fourth quarter of 2025, aiming for a transformative treatment for Fabry disease patients [3][4]. Clinical Study Insights - The Phase 1/2 STAAR study presented at ICIEM2025 showed that isaralgagene civaparvovec could provide meaningful multi-organ clinical benefits and demonstrated a positive mean annualized eGFR slope at 52 weeks across all patients [3][5]. - The STAAR study is a global, open-label, single-dose, dose-ranging clinical trial designed to evaluate the gene therapy in Fabry disease patients, requiring only a one-time infusion [5]. Regulatory Designations - Isaralgagene civaparvovec has received multiple designations from regulatory bodies, including Orphan Drug, Fast Track, and RMAT from the FDA, as well as Orphan Medicinal Product designation from the European Medicines Agency [4].