Taysha Gene Therapies (NASDAQ:TSHA) expects to report pivotal trial data for its experimental Rett syndrome gene therapy TSHA-102 and provide feedback from U.S. regulators on a potential filing pathway in the first half of 2027, executives said on the company’s third-quarter earnings call.
The company is evaluating whether a six-month interim analysis of the REVEAL pivotal trial could support a biologics license application, or BLA, rather than waiting for 12-month data. Chief Executive Officer Sean Nolan said a filing based on the interim analysis could accelerate the submission timeline by at least two quarters, though the approach remains subject to the data and discussions with the Food and Drug Administration.
Taysha also reported a wider third-quarter net loss as clinical trial and commercial-readiness expenses increased. It ended September with $422.8 million in cash and cash equivalents, which management expects to fund planned operations into the second half of 2028.
Trial data and FDA discussions ahead
All 33 patients treated with TSHA-102 across the REVEAL and ASPIRE studies have passed the acute post-dosing safety monitoring period associated with AAV gene therapies, Nolan said. As of the November 2026 data cutoff, the company reported no severe treatment-related serious adverse events or dose-limiting toxicities across the program.
President and Head of R&D Suku Nagendran said no treatment-related serious adverse events had been reported in the ASPIRE trial, which includes participants as young as two and three years old.
Asked about a previously reported peripheral neuropathy event in one patient, Nagendran said the patient had pre-existing clinical evidence of sensory neuropathy and was hospitalized after symptoms worsened. He said she was recovering and was close to, but had not yet returned to, her pre-treatment baseline.
The final pivotal trial participant was expected to reach the six-month assessment in December, Nolan said. Taysha plans to review the data, request an FDA meeting and release the results alongside the agency’s feedback rather than publishing the findings before that discussion. Nolan said the meeting could occur later in the first quarter of 2027, with meeting minutes arriving that quarter or early in the second quarter.
Nolan said approximately one-third of patients would need to respond to meet the trial’s statistical threshold. He said the FDA would also consider the broader evidence, including secondary endpoints and longer-term data from the earlier REVEAL Part A study. Taysha continues to see a potential filing path using either the six-month or 12-month pivotal data.
For the interim analysis, the company will evaluate only the first six months of data for each patient; later data will remain blinded for the 12-month assessment, Nolan said. He added that Taysha would share the 12-month results even if it files using the interim data.
Manufacturing and launch preparations
Taysha completed its BLA-enabling process performance qualification manufacturing campaign for TSHA-102 in the fourth quarter, Nolan said. He said process parameters and analytical results met predefined product specifications and comparability criteria for commercial product and clinical trial material.
The company plans to discuss the manufacturing results and other chemistry, manufacturing and controls matters with the FDA at a Type B meeting expected in the fourth quarter. Chief of Staff and Technical Operations Officer Fred Porter said the batches were manufactured at the commercial Harmans facility in Maryland.
Nolan said the commercial manufacturing process consistently produced a single-digit percentage of empty capsids. He described the lower percentage as a potential safety and cost benefit, but said it probably would not appear in the product label.
Taysha has also expanded its payer team and held pre-approval information-sharing discussions with insurers. Nolan said the company has worked with manufacturing partner Catalent on expected demand and does not foresee a supply constraint if TSHA-102 reaches the market.
Loss widens as spending rises
Third-quarter research and development expenses rose to $28.8 million from $25.7 million a year earlier, primarily because of higher clinical trial costs and increased compensation associated with additional headcount, Chief Financial Officer Kamran Alam said.
General and administrative expenses increased to $13.1 million from $8.3 million, reflecting higher compensation, consulting and professional fees, including spending on launch readiness. Net loss widened to $39.1 million, or $0.10 per share, from $32.7 million, or $0.09 per share, a year earlier.
Beyond TSHA-102, Taysha expects to nominate an additional gene therapy development candidate targeting a central nervous system disorder and begin preclinical work in the first half of 2027. The company did not identify the planned indication on the call.
About Taysha Gene Therapies (NASDAQ:TSHA)
Taysha Gene Therapies is a biotechnology company focused on developing gene therapies for rare, genetically driven diseases. Based in Dallas, Texas, the company was founded in 2019 and has built its programs around adeno-associated virus delivery technology. The company’s lead program, TSHA-102, is an investigational gene therapy being developed for Rett syndrome, a rare neurological disorder. Taysha’s research has also included gene therapy programs for other rare diseases, including giant axonal neuropathy.
