Taysha Gene Therapies, Inc ( TSHA ). stock is trading lower on Friday, with a session volume of 4.695 million, as per data from Benzinga Pro.

On Thursday, during after-hours trading, the company said it regained full rights to its lead TSHA-102 program in clinical evaluation for Rett syndrome.

TSHA-102 is a self-complementary intrathecally delivered AAV9 investigational gene transfer therapy in clinical evaluation for Rett syndrome.

Rett syndrome is a rare neurodevelopmental disorder caused by mutations in the X-linked MECP2 gene encoding methyl CpG-binding protein 2 (MeCP2), essential for regulating brain neuronal and synaptic function.

The disorder is characterized by loss of communication and hand function, slowing and/or regression of development, motor and respiratory impairment, seizures, intellectual disabilities, and shortened life expectancy.

The 2022 Option Agreement between Astellas Pharma, Inc ( ALPMF ) (OTC:ALPMY) and Taysha, which had granted Astellas the exclusive option to enter a negotiation period to obtain an exclusive license to TSHA-102 in Rett syndrome and certain rights with respect to change in control transactions involving Taysha, has expired.

Taysha delivered a TSHA-102 data package to Astellas in mid-2025 that contained the previously disclosed Part A REVEAL Phase 1/2 adolescent/adult and pediatric trials clinical data (May 2025 data cutoff).

100% of pediatric, adolescent, and adult patients gained ≥ one defined developmental milestone across the core functional domains of fine motor, gross motor, and communication post-TSHA-102, with a ~0% likelihood of being achieved without treatment based on natural history data.

Taysha has finalized FDA alignment on the REVEAL pivotal trial protocol and statistical analysis plan, which includes a 6-month interim analysis that may serve as the basis for BLA submission.

Price Action: TSHA stock was trading lower by 11.42% to $4.500 at last check Friday. ALPMF was down 8.81%.

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