Tenaya Therapeutics to Present New TN-201 Trial Data at ACC Meeting

Tenaya Therapeutics, Inc., a clinical-stage biotechnology company based in South San Francisco, announced promising interim results from its MyPEAK-1 Phase 1b/2 clinical trial for the investigational gene therapy TN-201. This therapy is aimed at treating Myosin Binding Protein C3 (MYBPC3)-associated hypertrophic cardiomyopathy (HCM), a genetic heart condition caused by mutations in the MYBPC3 gene leading to insufficient levels of myosin-binding protein C (MyBP-C). This condition often progresses aggressively and can lead to severe complications.

The first three patients in the trial, who received a one-time infusion of TN-201, exhibited encouraging outcomes. The treatment appeared well tolerated at a 3E13 vg/kg dose, with adverse effects being mild and manageable. The study presented data from serial biopsies and assessments showing sustained presence of TN-201 DNA in heart tissues and robust RNA expression that increased significantly over time. MyBP-C protein levels showed a noticeable increase, indicating successful transduction and expression of the therapeutic gene. A reduction in cardiac troponin, a marker of myocardial injury, was observed in two patients, suggesting a decrease in heart damage.

Additionally, improvement in key measures of heart hypertrophy was noted in two patients, where left ventricular posterior wall thickness decreased into normal ranges, and left ventricular mass showed a 10% improvement in one patient. Notably, all participants initially classified with severe disease symptoms experienced an improvement to New York Heart Association (NYHA) Class I status, indicating no limitations on physical activity.

Dr. Milind Desai, an investigator of the trial, emphasized the significance of these findings, highlighting TN-201 as the first gene therapy tested for HCM patients with MYBPC3 mutations. The therapy holds the potential to transform treatment by addressing the genetic cause of the disease. Whit Tingley, Chief Medical Officer of Tenaya, expressed optimism about the implications of these results and looks forward to further data from the ongoing trials.

The company plans to complete the enrollment of the high-dose cohort, Cohort 2, by the first half of 2025 and anticipates reporting initial data later that year. This cohort will receive a higher dose of 6E13 vg/kg. Interim results from the first cohort have provided the necessary safety data to expand eligibility criteria and enroll additional patients.

Research presented at the American College of Cardiology Scientific Sessions also highlighted the disease burden of MYBPC3-associated HCM compared to other HCM populations. Younger patients with this genetic variant were shown to have more rapid disease progression and increased risk of serious cardiac events. The study underlines the urgent need for therapies that address the genetic roots of such diseases.

Tenaya Therapeutics is committed to advancing its pipeline of genetic medicines, including TN-201, to potentially offer curative treatments for heart conditions. The company has been given several designations by the U.S. FDA, reflecting the therapy's promise for addressing rare pediatric and orphan diseases.

The ongoing MyPEAK-1 trial is a multi-center, open-label study designed to evaluate the safety, tolerability, and efficacy of TN-201. It aims to enroll adults with symptomatic MYBPC3-associated HCM, investigating the effects of different doses. By targeting the underlying genetic cause of MYBPC3-associated HCM, TN-201 offers the hope of halting, or even reversing, the progression of this severe condition with a single administration.