Solid Biosciences expects to initiate phase 1b trial in 4Q

Solid Biosciences expects to initiate phase 1b trial in 4Q

Title: Solid Biosciences Secures FDA and Health Canada Approvals for CPVT Gene Therapy, Plans Phase 1b Trial

Solid Biosciences Inc. (Nasdaq: SLDB), a precision genetic medicine company, has received significant regulatory approvals for its novel gene therapy, SGT-501, designed to treat catecholaminergic polymorphic ventricular tachycardia (CPVT). The company announced on July 8, 2025, that the U.S. Food and Drug Administration (FDA) has granted Investigational New Drug (IND) approval, and Health Canada has approved a clinical trial application (CTA) for SGT-501 [1].

SGT-501 is an AAV-based gene therapy candidate that delivers a functional, full-length, codon-optimized copy of the human cardiac calsequestrin (CASQ2) gene to heart muscle cells. This approach aims to increase CASQ2 protein levels, enhancing calcium buffering in the sarcoplasmic reticulum and stabilizing the ryanodine receptor (RYR2). The stabilization of RYR2 in its closed conformation supports the maintenance of normal cardiac rhythm, potentially protecting against ventricular tachycardia [1].

The approval of SGT-501 marks a critical development in the treatment of CPVT, a highly malignant, arrhythmogenic channelopathy caused by genetic mutations in the RYR2 and CASQ2 genes. CPVT is characterized by abnormal heart rhythms triggered by adrenergic stimulation, leading to unexplained fainting, seizures, cardiac arrest, and sudden death. Currently, there are no treatments that address the underlying mechanisms of CPVT [1].

Solid Biosciences expects to initiate a Phase 1b clinical trial of SGT-501 in the fourth quarter of 2025. The trial will evaluate the safety, tolerability, and efficacy of the gene therapy in individuals living with CPVT. This trial is part of Solid's expanding clinical pipeline, which now includes the company's first cardiac indication with an urgent unmet medical need [1].

Dr. Gabriel Brooks, Chief Medical Officer of Solid Biosciences, commented, "Despite being identified nearly 50 years ago, CPVT still lacks FDA-approved therapies. This announcement reflects a critical development in the treatment of this underserved, often fatal, cardiac disease. SGT-501 offers a precision genetic approach targeting the underlying pathophysiology of the disease: abnormal calcium releases from the sarcoplasmic reticulum in an otherwise structurally sound heart. We believe SGT-501 has the unique potential to provide durable protection and may be capable of liberating patients from the ever-present threat of lethal arrhythmias and life-limiting prohibitions on exercise. Solid is proud to launch this program to help address this clear unmet need, further expanding our pipeline of differentiated and thoughtfully designed genetic medicines" [1].

Dr. Silvia Priori, Professor of Cardiology at the University of Pavia and Director of the Molecular Cardiology Unit at the IRCCS Maugeri in Pavia, Italy, expressed her enthusiasm for the development of SGT-501. "After decades during which we, the clinical community, have been limited in our ability to treat people living with CPVT, I have long hoped for the day when a genetic-modifying therapy becomes available. We are proud to partner with Solid who advanced fundamental work from our labs at Maugeri, which demonstrated the principle that calsequestrin overexpression can have a therapeutic impact on multiple forms of CPVT in both cellular and mouse models of disease. This work was further developed into a compelling IND safety and efficacy package through close collaboration with, and studies conducted by, the Solid team. I look forward to clinical updates for SGT-501 and seeing how this potential medicine may benefit people living with CPVT who are in critical need of disease-specific medicines" [1].

Solid Biosciences' SGT-501 has received Orphan Drug Designation and Rare Pediatric Disease Designation from the U.S. FDA. This designation reflects the company's commitment to developing innovative treatments for rare and pediatric diseases. The gene therapy candidate has the potential to be a first-in-class therapy to correct the underlying RYR2 instability and calcium dysregulation causes of CPVT [1].

References
[1] https://www.globenewswire.com/news-release/2025/07/08/3112195/0/en/Solid-Biosciences-Announces-FDA-IND-and-Health-Canada-CTA-Approval-for-First-in-Class-Cardiac-Gene-Therapy-to-Treat-Catecholaminergic-Polymorphic-Ventricular-Tachycardia-CPVT.html