Taysha Gene Therapies Receives RMAT Designation from FDA for TSHA-102 in Rett Syndrome

Taysha Gene Therapies, Inc. has announced that the U.S. Food and Drug Administration (FDA) has granted Regenerative Medicine Advanced Therapy (RMAT) designation to its investigational gene therapy, TSHA-102. This therapy is currently being evaluated for the treatment of Rett syndrome, a severe neurodevelopmental disorder with no approved therapies that directly address the genetic malfunction at its root.

Rett syndrome is a rare condition caused by mutations in the MECP2 gene, vital for neuronal and synaptic function in the brain. The disorder typically affects females and manifests through loss of communication, motor impairments, seizures, and intellectual disabilities, leading to a significantly shortened life expectancy. Progression of the syndrome occurs in four stages, starting with early onset stagnation, followed by rapid regression, a plateau phase, and ultimately late motor deterioration.

TSHA-102 is a self-complementary intrathecally delivered AAV9 gene transfer therapy. It aims to deliver a functional MECP2 gene to cells in the central nervous system (CNS), thereby addressing the genetic cause of Rett syndrome. The therapy employs a novel miRNA-Responsive Auto-Regulatory Element (miRARE) technology to regulate MECP2 levels within cells, avoiding the risks associated with overexpression.

The RMAT designation was based on safety and efficacy data from the first three patients dosed with the low dose of TSHA-102 in both the REVEAL Phase 1/2 trials, involving adolescent/adult and pediatric cohorts. This designation is significant because it accelerates the development and review processes for promising regenerative medicine therapies intended to treat, modify, reverse, or cure serious conditions with unmet medical needs. Companies that receive RMAT designation benefit from increased FDA interactions, with the goal of expediting drug development and review.

Dr. Sukumar Nagendran, President and Head of R&D at Taysha, emphasized that the RMAT designation underscores the high unmet medical need in Rett syndrome and the potential of TSHA-102 to transform its treatment landscape. He noted that the FDA’s recognition supports the gene therapy candidate’s promise in bringing meaningful change to patients and their families.

Chief Regulatory Officer Rumana Haque-Ahmed added that Taysha remains dedicated to advancing TSHA-102 to potentially modify the disease and address the genetic root cause of Rett syndrome. The RMAT designation facilitates this goal by promoting increased dialogue with the FDA, thus expediting the development plan for TSHA-102. The company is eager to continue collaboration with regulatory agencies to advance the TSHA-102 program.

TSHA-102 is undergoing evaluation in the REVEAL Phase 1/2 trials across different age groups in Canada, the U.S., and the U.K. Besides the RMAT designation, TSHA-102 has also received Fast Track, Orphan Drug, and Rare Pediatric Disease designations from the FDA. Additionally, it has been granted Orphan Drug designation by the European Commission and Innovative Licensing and Access Pathway designation from the Medicines and Healthcare products Regulatory Agency in the U.K.

Taysha Gene Therapies, headquartered in Dallas, Texas, is a clinical-stage biotechnology company dedicated to developing adeno-associated virus (AAV)-based gene therapies for severe monogenic diseases of the CNS. With a strong management team experienced in gene therapy development and commercialization, Taysha focuses on rapidly advancing transformative medicines from research to patient care, leveraging a proven AAV9 capsid manufacturing process. The company’s mission is to address the critical unmet medical needs of patients and significantly enhance their quality of life and that of their caregivers.