Taysha Gene Therapies, Inc. Q2 FY2025 earnings call

Key Points:

• TSHA-102 program progress: Aligned with FDA and Health Canada for REVEAL pivotal trial, reported positive clinical data, and strengthened balance sheet.
• REVEAL pivotal trial: Site activation commenced, anticipates Q4 patient enrollment; Part A data shows 100% response rate for primary endpoint, safety of low and high doses well tolerated.
• Natural history data: Established developmental plateau population (age 6+ with ~0% milestone gain), underpinning pivotal trial design.
• CMC progress: Pivotal TSHA-102 product released and cleared for trial; FDA approved pivotal lot comparable to clinical material.
• Financial: R&D and G&A expenses increased, but cash runway extended into 2028 via financing and debt refinancing.

Research and development expenses for the three months ended June 30, 2025 were $20.1 million compared to $15.1 million in the same period in 2024. General and administrative expenses were $8.6 million in 2025 vs. $7.3 million in 2024. Net loss for the quarter was $26.9 million or $0.09 per share vs. $20.9 million or $0.09 per share in 2024. As of June 30, 2025, Taysha had $312.8 million in cash and cash equivalents, reflecting proceeds from a follow-on financing and refinanced debt.

Forward-Looking:

• Anticipates Q4 patient enrollment for REVEAL pivotal trial.
• Plans to report new supplemental clinical data from Part A of REVEAL Phase I/II trials in Q4.
• Confident in path to TSHA-102 registration with regulatory agencies (FDA, Health Canada) based on progress to date.

Risks:

• Forward-looking statements may not materialize due to various risks (e.g., regulatory uncertainties, disease heterogeneity).
• Actual results may differ from forward-looking statements due to factors like clinical trial outcomes, regulatory approvals, and market dynamics.

Q: Given the 100% response rate for the pivotal trial primary endpoint in Part A, is this the bar for Part B?

A: Results in Part A are compelling, but the statistical plan for Part B considers a low spontaneous milestone gain rate (6.7%), with a 15-patient population making the bar relatively low.

Q: Are the benefits of the gene therapy plateauing?

A: Gains are seen over time; critical gains improving daily functioning may not be captured in milestones but are still major improvements.

Q: How does Taysha's gene therapy differentiate from competitors?

A: Data-driven approach, minimally invasive lumbar intrathecal administration (reducing systemic exposure), safety, and efficacy demonstrated in Part A data.

Q: Will there be pushback on using an interim readout to support BLA filing?

A: Discussions with FDA supportive of a 6-month interim analysis, focusing on analysis particulars rather than overturning trial design.

Q: What are expectations for Q4 data?

A: More granular data on video-documented milestones and outcomes will be shared, to be presented at medical conferences and company updates.

Q: Where do regulatory interactions stand with FDA, Health Canada, and Europe?

A: Health Canada received a no-objection letter for CTA amendment; FDA IND amendment ongoing with constructive dialogue; European scientific advice meeting scheduled for early fall.