Tenaya Reports Interim TN-201 Data in MYBPC3-Associated HCM

Tenaya Therapeutics has reported new interim data from its ongoing MyPEAK-1 phase 1b/2 trial showing that treatment with TN-201 gene therapy was associated with improvements in multiple clinical measures among patients with MYBPC3-associated hypertrophic cardiomyopathy (HCM), an inherited form of heart disease for which no approved therapies address the underlying genetic cause.¹

The updated analysis includes follow-up ranging from 78 to 104 weeks for three patients treated in the lower-dose cohort and 26 to 52 weeks for four patients treated in the higher-dose cohort. Six patients were evaluable for efficacy endpoints as of the May 2026 data cutoff. According to the company, all evaluable patients demonstrated improvements in measures of cardiac hypertrophy as well as at least one indicator of symptom burden.¹

“It's encouraging to see patients' symptoms, functional capacity and measures of cardiac hypertrophy—the key feature of their disease—consistently improving in MyPEAK-1,” said Whit Tingley, MD, PhD, chief medical officer of Tenaya Therapeutics, in a company statement.¹

What did investigators observe in measures of cardiac remodeling?

A key finding from the interim analysis was evidence of reductions in left ventricular hypertrophy, a defining characteristic of HCM. All six evaluable patients experienced decreases in left ventricular mass index (LVMI), while five patients showed reductions in one or more measures of ventricular wall thickness.¹

The company reported that decreases in LVMI observed in the first cohort were maintained for up to two years following treatment. Patients treated at the higher dose level appeared to demonstrate reductions in LVMI at earlier post-treatment timepoints than those in the lower-dose cohort.¹

Investigators also reported that cardiac biomarkers either improved or remained stable in most participants. Cardiac troponin levels improved or remained stable in five of six patients, while NT-proBNP levels improved in three patients.¹

How did TN-201 affect symptoms and functional capacity?

According to the interim dataset, treatment with TN-201 was associated with improvements in patient-reported and physician-assessed symptom measures. Five of six evaluable patients improved by at least one New York Heart Association (NYHA) functional class and were classified as NYHA Class I at their most recent assessment. The remaining patient remained stable.¹

Four patients experienced clinically meaningful improvements in Kansas City Cardiomyopathy Questionnaire Clinical Summary Scores, with gains ranging from 12 to 56 points from baseline. A change of at least five points is generally considered clinically meaningful.¹

Functional capacity assessments also showed improvement in some participants. Three patients demonstrated meaningful gains in six-minute walk test performance, with increases ranging from 50 to 255 meters compared with baseline. One patient in the higher-dose cohort also experienced clinically meaningful improvement in peak oxygen consumption during cardiopulmonary exercise testing.¹

What safety findings were reported?

TN-201 was reported to be generally well tolerated at both dose levels evaluated in the study. No new treatment-related safety events were identified since the previous data update, and no dose-limiting toxicities were observed.¹

The company stated that all treated patients have completed immunosuppressive therapy tapering. Modifications to monitoring and immunosuppression strategies implemented following treatment of the first cohort resulted in shorter corticosteroid exposure in the higher-dose cohort despite administration of a larger dose of gene therapy.¹

Biopsy analyses also demonstrated evidence of gene transfer and expression. Serial cardiac biopsies showed TN-201 DNA transduction and messenger RNA expression, while MyBP-C protein levels increased over time in four of six patients evaluated.¹

What regulatory developments accompanied the data update?

Alongside the clinical update, Tenaya announced that TN-201 has received PRIority MEdicines (PRIME) designation from the European Medicines Agency. The company also reported that a pediatric indication for biallelic MYBPC3-associated HCM has been accepted into the FDA's Rare Disease Evidence Principles process.¹

PRIME designation is intended to support development of medicines that may address unmet medical needs through early engagement with regulators, while the RDEP initiative facilitates discussions regarding evidence generation strategies for therapies targeting ultra-rare diseases.¹

Tenaya said it plans to continue enrolling patients at the 6E13 vg/kg dose level and expects to provide additional long-term follow-up data during the second half of 2026.¹

References

1. Tenaya Therapeutics Announces Interim Data from MyPEAK-1 Showing Treatment of MYBPC3-associated HCM with TN-201 Gene Therapy Resulted in Consistent Signs of Cardiac Remodeling and Reductions in Symptom Burden. (2026 Jun 3). Business Insider. https://markets.businessinsider.com/news/stocks/tenaya-therapeutics-announces-interim-data-from-mypeak--1-showing-treatment-of-mybpc3-associated-hcm-with-tn-201-gene-therapy-resulted-in-consistent-signs-of-cardiac-remodeling-and-reductions-in-1036221046