Sangamo Therapeutics, Inc. (Nasdaq: SGMO), a genomic medicine company, today announced that the U.S. Food and Drug Administration (FDA) has accepted Sangamo's request for a rolling submission and review of the Biologics License Application (BLA) for isaralgagene civaparvovec, or ST-920, a wholly owned investigational gene therapy for the treatment of adults with Fabry disease.
This acceptance follows Sangamo's meeting with the FDA in October 2025 to discuss the proposed efficacy and safety data package for isaralgagene civaparvovec where, in the meeting minutes, among other things, the FDA reiterated its October 2024 agreement to use eGFR slope as an endpoint to support an accelerated approval pathway.
"We are pleased to have received acceptance of our rolling submission and review request from the FDA, which follows our recent meeting to discuss the proposed efficacy and safety data package," said Nathalie Dubois-Stringfellow, Ph. D, Chief Development Officer at Sangamo. "We are excited by the potential of ST-920 to provide a potentially transformative treatment for Fabry disease patients and look forward to initiating rolling submission of the BLA later this quarter."
Sangamo presented detailed clinical data from the registrational Phase 1/2 STAAR study at the International Congress of Inborn Errors of Metabolism 2025 (ICIEM2025) in September, which demonstrated the potential for isaralgagene civaparvovec as a one-time, durable treatment of underlying pathology of Fabry disease to provide meaningful, multi-organ, clinical benefits above current standards of care. Furthermore, the STAAR study demonstrated a positive mean annualized estimated glomerular filtration rate (eGFR) slope at 52-weeks across all dosed patients in the study, which the FDA has agreed will serve as the primary basis of approval.
Isaralgagene civaparvovec has been granted Orphan Drug, Fast Track and RMAT designations from the FDA, Orphan Medicinal Product designation and PRIME eligibility from the European Medicines Agency and Innovative Licensing and Access Pathway from U.K. Medicines and Healthcare products Regulatory Agency.
Sangamo plans to initiate rolling submission of the BLA to the FDA under the accelerated approval pathway later in the fourth quarter of 2025.
About the STAAR Study
The Phase 1/2 STAAR study is a global open-label, single-dose, dose-ranging, multicenter clinical study designed to evaluate isaralgagene civaparvovec, or ST-920, a gene therapy product candidate in patients with Fabry disease. Isaralgagene civaparvovec requires a one-time infusion without preconditioning.
About Fabry Disease
Fabry disease is a lysosomal storage disorder caused by mutations in the galactosidase alpha gene (GLA), which leads to deficient alpha-galactosidase A (α-Gal A) enzyme activity, which is necessary for metabolizing globotriaosylceramide (Gb3). The buildup of Gb3 in the cells can cause serious damage to vital organs, including the kidney, heart, nerves, eyes, gut and skin. Symptoms of Fabry disease can include decreased or absent sweat production, heat intolerance, angiokeratoma (skin blemishes), vision problems, kidney disease, heart failure, gastrointestinal disturbance, mood disorders, neuropathic pain and tingling in the extremities.
About Sangamo Therapeutics
Sangamo Therapeutics is a genomic medicine company dedicated to translating ground-breaking science into medicines that transform the lives of patients and families afflicted with serious neurological diseases who do not have adequate or any treatment options. Sangamo believes that its zinc finger epigenetic regulators are ideally suited to potentially address devastating neurological disorders. Moreover, Sangamo's SIFTER capsid discovery platform is advancing delivery to the central nervous system in preclinical studies. Sangamo is also progressing next generation genome editing through its modular integrase (MINT) platform. Sangamo's pipeline includes multiple partnered programs and programs with opportunities for partnership and investment. To learn more, visit www.sangamo.com and connect with us on LinkedIn and Twitter/X .
Forward-Looking Statements
This press release contains forward-looking statements regarding Sangamo's current expectations. These forward-looking statements include, without limitation, statements relating to: the safety and efficacy and therapeutic potential of isaralgagene civaparvovec, including the potential for it to be a one-time, durable treatment option for Fabry disease to provide meaningful, multi-organ clinical benefits above current standards of care; the presentation of clinical data from the Phase 1/2 STAAR study; the potential for isaralgagene civaparvovec to qualify for the FDA's accelerated approval program, including the adequacy of data generated in the Phase 1/2 STAAR study to support any such approval; expectations concerning the availability of additional data to support a potential BLA submission for isaralgagene civaparvovec, and the timing of such submissions; and other statements that are not historical fact. These statements are not guarantees of future performance and are subject to certain risks and uncertainties that are difficult to predict. Factors that could cause actual results to differ include, but are not limited to, risks and uncertainties related to Sangamo's lack of capital resources to obtain regulatory approval for and commercialize its product candidates in a timely manner or at all, including the ability to secure a collaboration partner for ST-920; the uncertain timing and unpredictable nature of clinical trial results, including the risk that preliminary or topline data is not indicative of final results, that the therapeutic effects observed in the latest clinical data from the Phase 1/2 STAAR study will not be durable in patients and that final clinical trial data from the study will not validate the safety and efficacy of isaralgagene civaparvovec, including that the 52-week data from the Phase 1/2 STAAR study will not support a BLA submission and/or that the 104-week data from such study will not verify the clinical benefit of isaralgagene civaparvovec or support FDA approval, and that the patients withdrawn from ERT will remain off ERT; Sangamo's need for substantial additional funding to execute its operating plan and to continue to operate as a going concern; the effects of macroeconomic factors or financial challenges on the global business environment, healthcare systems and Sangamo's business and operations; the research and development process; the unpredictable regulatory approval process for product candidates across multiple regulatory authorities; the potential for technological developments that obviate technologies used by Sangamo; Sangamo's reliance on collaborators and the potential inability to secure additional collaborations; and Sangamo's ability to achieve expected future financial performance.
All forward-looking statements about Sangamo's future plans and expectations, including Sangamo's development plans for its product candidates, are subject to Sangamo's ability to secure adequate additional funding. There can be no assurance that Sangamo and its current or potential future partners will be able to develop commercially viable products. Actual results may differ materially from those projected in these forward-looking statements due to the risks and uncertainties described above and other risks and uncertainties that exist in the operations and business environments of Sangamo and its collaborators. These risks and uncertainties are described more fully in Sangamo's Securities and Exchange Commission, or SEC, filings and reports, including in Sangamo's Annual Report on Form 10-K for the year ended December 31, 2024, as supplemented by its Quarterly Report on Form 10-Q for the quarter ended September 30, 2025, each filed with the SEC, and future filings and reports that Sangamo makes from time to time with the SEC. Forward-looking statements contained in this announcement are made as of this date, and Sangamo undertakes no duty to update such information except as required under applicable law.
Contacts
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Louise Wilkie
ir@sangamo.com
Media Inquiries
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