Solid Biosciences Inc. has announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to SGT-212, a gene therapy candidate for the treatment of Friedreich's ataxia (FA). This designation aims to expedite the development and review of SGT-212, which is designed to address both the neurological and cardiac manifestations of FA through a dual route of administration. The planned Phase 1b trial is set to begin in the second half of 2025.
Targeting Neurological and Cardiac Symptoms
Friedreich's ataxia is a debilitating, inherited disease affecting approximately 5,000 people in the United States and 15,000 in Europe. It is caused by mutations in the FXN gene, leading to reduced production of the frataxin protein, which is essential for mitochondrial function. This deficiency results in progressive nervous system damage, movement problems, and cardiac dysfunction. Cardiac complications are the primary cause of death in FA patients.
SGT-212 is a recombinant adeno-associated virus (AAV)-based gene replacement therapy designed to deliver a functional copy of the human frataxin (FXN) gene. What sets SGT-212 apart is its dual route of administration: intravenous (IV) infusion to target the heart and direct intradentate nucleus (IDN) infusion into the cerebellum, a brain region critical for coordination. The IDN infusion uses an MRI-guided device to ensure precise delivery.
According to Bo Cumbo, President and CEO of Solid Biosciences, SGT-212 is intentionally designed for highly targeted delivery to both the dentate nuclei and cardiac tissue. Preclinical data supported the IND application, demonstrating safe gene transfer and frataxin expression in target tissues, with significant restoration of neurologic function and reversal of cardiac implications in mice.
Fast Track Designation Benefits
The FDA's Fast Track program is designed to accelerate the development and review of drugs that treat serious conditions and fill unmet medical needs. With this designation, Solid Biosciences will benefit from more frequent interactions with the FDA and may be eligible for priority review, potentially bringing SGT-212 to patients sooner.
Jessie Hanrahan, Ph.D., Chief Regulatory Officer at Solid Biosciences, expressed gratitude for the FDA's recognition of the unmet needs within the FA community and the potential of SGT-212 to bring meaningful change to their lives. She added that they look forward to working closely with the Agency to discuss the most effective and expeditious development pathway for SGT-212 to pursue future marketing authorization.
Upcoming Clinical Trial
Solid Biosciences plans to initiate a first-in-human, open-label, dose-finding Phase 1b clinical trial of SGT-212 in the second half of 2025. The study will enroll both non-ambulatory and ambulatory adult patients with FA across up to three cohorts. The primary goals are to evaluate the safety and tolerability of SGT-212, with participants being followed for five years post-treatment.
Jennifer Farmer, CEO of the Friedreich's Ataxia Research Alliance (FARA), congratulated Solid Biosciences on this significant milestone. She highlighted the importance of gene therapy approaches in addressing the underlying causes of FA and the unmet medical needs of the patient community. Farmer noted that SGT-212's unique, precision approach targets both the cerebellum and cardiac tissue using a dual route of administration, aiming to address the underlying cause of the disease and its progression.
With approximately 5,000 individuals in the United States and 15,000 in Europe affected by FA, and no existing treatments that can cure or halt the disease's progression, SGT-212 represents a promising advancement in the field of gene therapy for this devastating condition.
