FDA Grants Taysha Rare Pediatric Disease Designation for SLC13A5 Deficiency Candidate

Rare Daily Staff

The U.S. Food and Drug Administration granted Taysha Gene Therapies Rare Pediatric Disease and Orphan Drug designations for TSHA-105, an AAV9-based gene therapy in development for SLC13A5-related epilepsy.

SLC13A5 is a form of infantile epilepsy caused by mutations in the SLC13A5 gene. The disorder is an autosomal recessive disorder, so two copies of the mutated gene must be inherited to affect an infant. The condition causes developmental delay and seizures beginning within the first few days of life.

“There are no approved therapies for epilepsy caused by SLC13A5 that address the underlying cause of this disease,” said RA Session II, founder, president, and CEO of Taysha. “We are encouraged by the early evidence of TSHA-105’s disease-modifying approach and believe these designations will help us potentially accelerate the development of this exciting program. We look forward to working with the FDA to make TSHA-105 available to patients as expeditiously as possible.”

The FDA grants rare pediatric disease designation for serious and life-threatening diseases that primarily affect children ages 18 years or younger and fewer than 200,000 people in the United States. The designation makes TSHA-105 eligible for a Rare Pediatric Disease Priority Review voucher upon approval of the therapy by the FDA.

The vouchers can be used to reduce the time of an FDA new drug approval review to six months from ten months. The vouchers are potentially lucrative because they are transferable. Most recently, Rhythm Pharmaceutics sold its priority review voucher for $100 million in January 2021 to Alexion Pharmaceuticals.

Photo: RA Session II, founder, president, and CEO of Taysha