Taysha Gene Therapies Q1 2024 Financial Results and Corporate Update

Taysha Gene Therapies, Inc., a clinical-stage biotechnology company focused on adeno-associated virus (AAV)-based gene therapies for severe monogenic diseases of the central nervous system (CNS), has recently shared its financial outcomes for the first quarter ending March 31, 2024, along with significant corporate updates.

The company has made substantial progress in its TSHA-102 program, which is currently under clinical evaluation for Rett syndrome. The notable advancements in this program include early enrollment of the first patient in the high dose cohort of the REVEAL adolescent and adult trial, as well as the successful dosing of the second pediatric patient in the REVEAL pediatric trial. The FDA has granted TSHA-102 the Regenerative Medicine Advanced Therapy (RMAT) designation, following a review of safety and efficacy data from the first three patients dosed with the low dose of TSHA-102 in both adolescent/adult and pediatric trials. This designation is expected to facilitate accelerated development and review of the therapy by enhancing dialogue with the FDA.

TSHA-102 is being evaluated in the REVEAL Phase 1/2 adolescent and adult trial, conducted across Canada and the U.S. This trial is an open-label, randomized, dose-escalation and dose-expansion study aimed at assessing the safety and preliminary efficacy of TSHA-102 in adolescent and adult females aged 12 years and older with Rett syndrome caused by a MECP2 loss-of-function mutation. The therapy is administered as a single lumbar intrathecal injection. The dose escalation phase will sequentially evaluate two dose levels, and the maximum tolerated or administered dose established will be used in the dose expansion phase.

The first cohort, which received a low dose of 5.7x10^14 total vector genomes (vg), has completed dosing. Longer-term data from this cohort, which included two adult patients with stage four Rett syndrome, indicated that TSHA-102 was generally well tolerated, with no treatment-related serious adverse events. Improvements were observed in multiple clinical domains including motor skills, socialization/communication, autonomic function, and seizure stability. The first patient in the high dose cohort (1x10^15 total vg) has been enrolled, with dosing scheduled for the second quarter of 2024.

The REVEAL Phase 1/2 pediatric trial, conducted in the U.S. and U.K., also follows an open-label, randomized, dose-escalation and dose-expansion design. It aims to determine the maximum administered or tolerated dose of TSHA-102 in pediatric females aged 5 to 8 years old. The dose expansion phase will evaluate the therapy in two age cohorts (5 to 8 years and 3 to 5 years). The second pediatric patient in the low dose cohort has been dosed following an Independent Data Monitoring Committee (IDMC) review.

Several key milestones are anticipated for 2024. In the REVEAL adolescent and adult trial, dosing of the first patient in the high dose cohort is scheduled for the second quarter. An update on the safety and efficacy data from the completed low dose cohort is expected mid-2024, with initial data from the high dose cohort anticipated in the second half of the year. Similarly, in the REVEAL pediatric trial, initial data from the low dose cohort is expected mid-2024, with preliminary data from the high dose cohort expected in the latter half of the year.

Financially, Taysha reported research and development expenses of $20.7 million for the first quarter of 2024, up from $12.5 million in the same period in 2023. This increase was primarily due to heightened clinical trial activities and Good Manufacturing Practice (GMP) batch processes for TSHA-102. General and administrative expenses decreased to $7.1 million from $8.8 million, attributed to lower headcount and reduced consulting fees. The net loss for the quarter was $24.1 million, compared to $17.6 million in the previous year. As of March 31, 2024, Taysha had $124 million in cash and cash equivalents, projected to support operations into 2026.

Overall, Taysha Gene Therapies is making significant strides in the development of TSHA-102 for Rett syndrome, with promising clinical data and strategic financial management paving the way for potential future successes.