New Advance in Gene Therapy: Hope for Fabry Disease Treatment
On March 9, 2026, genomic medicine company Sangamo Therapeutics announced it is advancing the rolling submission of a Biologics License Application to the U.S. Food and Drug Administration for its gene therapy isaralgagene civaparvovec (development code ST-920), seeking accelerated approval as a new treatment option for adults with Fabry disease.
About ST-920 and the STAAR Study
ST-920 is an investigational gene therapy designed to be administered as a one-time infusion, aiming to provide long-term therapeutic effects for Fabry disease patients. Its pivotal registrational clinical trial is called the STAAR study.
Data from this study showed:
- All dosed patients demonstrated a positive mean annualized estimated glomerular filtration rate slope at 52 weeks, indicating improved kidney function.
- The FDA has agreed that this eGFR data can serve as an endpoint to support the accelerated approval pathway.
- The therapy was generally well-tolerated.
Based on these positive results, Sangamo believes ST-920 has the potential to be a one-time, well-tolerated, and durable treatment that provides meaningful, multi-organ clinical benefits, potentially fundamentally shifting the treatment paradigm for Fabry disease.
What is Fabry Disease?
Fabry disease is a rare inherited lysosomal storage disorder. Mutations in the GLA gene lead to deficient activity of the alpha-galactosidase A enzyme, which is necessary for metabolizing a fatty substance called globotriaosylceramide. The progressive accumulation of Gb3 in cells causes damage to vital organs including the kidneys, heart, nerves, and skin.
Common symptoms include:
- Decreased or absent sweating, heat intolerance
- Angiokeratomas (skin blemishes)
- Neuropathic pain, tingling in the hands and feet
- Kidney disease, heart failure
- Gastrointestinal issues, vision problems
Regulatory Progress and Future Outlook
Sangamo initiated the rolling submission in December 2025 and has been submitting completed modules, including preclinical and clinical sections, for FDA review. This process allows for sequential submission and concurrent review, potentially expediting the overall approval timeline.
Furthermore, a companion diagnostic antibody assay designed to screen patients for eligibility to receive ST-920 has been submitted and accepted for review by the FDA's Center for Devices and Radiological Health, seeking Premarket Approval.
ST-920 has received Orphan Drug, Fast Track, and Regenerative Medicine Advanced Therapy designations from the FDA, as well as PRIority MEdicines eligibility from the European Medicines Agency, highlighting its potential to address an unmet medical need.
Please note: This article is based on a company press release. The therapy discussed is still under regulatory review and has not received final approval.