Sangamo Shares Surge on FDA Fast-Track for Fabry Disease Gene Therapy
The U.S. regulator's acceptance of a rolling submission for ST-920 could accelerate the approval timeline for the one-time treatment, positioning it against established therapies.
Shares of Sangamo Therapeutics (NASDAQ: SGMO) jumped in pre-market trading on Friday after the company announced a significant regulatory milestone for its key gene therapy candidate, potentially speeding its path to market.
The U.S. Food and Drug Administration (FDA) has accepted Sangamo's request for a rolling submission of its Biologics License Application (BLA) for ST-920, a one-time treatment for Fabry disease. The decision, disclosed by the company in a press release, allows Sangamo to submit completed sections of its application for review as they are finished, rather than waiting for the entire package to be complete. This process is typically reserved for therapies that address a serious or life-threatening condition and can substantially shorten the drug approval timeline.
This development is a critical step forward for Sangamo, which is aiming to disrupt the multi-billion dollar market for Fabry disease treatments. Fabry disease is a rare genetic disorder caused by the lack of an enzyme called alpha-galactosidase A (α-Gal A), leading to a harmful buildup of a fatty substance in cells. This can result in severe organ damage, including kidney failure, heart complications, and stroke.
Current standard-of-care often involves enzyme replacement therapy (ERT), which requires patients to receive intravenous infusions every two weeks for life. Sangamo's ST-920 is designed as a single-infusion gene therapy that enables a patient's own body to produce functional α-Gal A, potentially offering a durable, long-term solution and freeing patients from the burden of chronic treatment.
The FDA's decision follows a previous agreement with Sangamo to pursue an Accelerated Approval pathway for ST-920. According to company announcements from October 2024, the agency agreed that the slope of kidney function decline, measured by the estimated glomerular filtration rate (eGFR), could serve as the primary basis for approval. This allowed Sangamo to avoid a lengthy additional registrational study, a move that analysts noted as a significant derisking event.
Data from Sangamo's Phase 1/2 STAAR study has been promising. Positive topline results announced in June 2025 showed that ST-920 not only stabilized but appeared to improve renal function, a key marker of disease progression. Furthermore, all 18 study participants who were on ERT at the beginning of the trial successfully withdrew from and remained off the treatment after receiving ST-920, while maintaining elevated α-Gal A activity.
The market for Fabry disease therapies is substantial and growing, with some analysts projecting it to reach over $7 billion by 2034. Sangamo is poised to compete with established treatments from companies like Sanofi and Takeda, as well as chaperone therapies from Amicus Therapeutics. The company also faces competition from other gene therapy developers, including Freeline Therapeutics and 4D Molecular Therapeutics, but the accelerated pathway could give ST-920 a first-mover advantage in the gene therapy space.
For investors, Friday's news provides a much-needed catalyst. Sangamo's stock, with a market capitalization of approximately $132 million, has traded near its 52-week low recently. However, the four analysts covering the stock have an average target price of $3.25, suggesting significant potential upside if the company can successfully navigate the final stages of regulatory approval and commercialization. With a BLA submission now expected to begin, Sangamo anticipates a potential commercial launch in the second half of 2026, marking a pivotal moment for the company and potentially for patients living with Fabry disease.