Tenaya Therapeutics (TNYA) investor relations material

Clinical trial progress and interim data

• Interim data from the MyPEAK-1 phase Ib/IIa trial of TN-201 for MYBPC3-associated HCM showed robust gene transduction, mRNA expression, and increased MyBP-C protein levels in all patients, with dose-dependent effects, including a 14% increase at 12 weeks in Cohort 2.

• All patients had severe, non-obstructive HCM, most with prior myectomy and persistent symptoms; improvements were seen in cardiac biomarkers (troponin I declined 48–74% to normal/near-normal, NT-proBNP improved or stabilized), hypertrophy, and heart failure symptoms.

• Reductions in left ventricular posterior wall thickness (21–39%) and LV mass index (12–22%) were observed in Cohort 1 at Week 52, with all patients showing improvements, some dropping below mortality-associated thresholds.

• Improvements in New York Heart Association class were sustained, with all Cohort 1 patients reaching Class 1 at one year, indicating no limitations from symptoms.

• TN-201 was well tolerated at both tested doses (3E13 and 6E13 vg/kg), with no dose-limiting toxicities or cardiotoxicity; most adverse events were mild, transient, or reversible, and all patients tapered off immunosuppression.

Regulatory and protocol updates

• The FDA placed a clinical hold on MyPEAK-1, requesting protocol amendments to standardize patient monitoring and immunosuppression; no recent safety events prompted this action.

• Revised protocols have been submitted, and discussions with the FDA have been collaborative and swift, with optimism for a quick resolution and no anticipated impact on development timelines or milestones.

• The changes are minor, focused on formalizing existing practices, and do not affect the interpretation or pooling of data for future pivotal studies.

Program overview and clinical context

• TN-201 is a first-in-class AAV9-based gene therapy targeting MYBPC3-associated HCM, a severe, progressive condition affecting 120,000 people in the US, with no approved therapies for most patients.

• The therapy delivers a functional MYBPC3 gene to heart muscle cells, aiming to restore MyBP-C protein, improve cardiac function, and halt or reverse disease progression.

• TN-201 has received Fast Track, Orphan Drug, and Rare Pediatric Drug designations from the FDA and orphan medicinal product designation from the European Commission.