Tenaya Therapeutics provides updates on MyPEAK-1 clinical trial of TN-201

Tenaya Therapeutics (TNYA) shared updates related to its ongoing Phase 1b/2 MyPEAK-1 clinical trial of TN-201. TN-201 is being developed for the potential treatment of MYBPC3-associated hypertrophic cardiomyopathy, or HCM, a condition caused by insufficient levels of myosin-binding protein C, or MyBP-C. TN-201 gene replacement therapy is designed to increase protein levels of MyBP-C to slow or even reverse the course of disease by delivering a functional copy of the MYBPC3 gene to heart muscle cells. Tenaya completed dosing of the first three patients at the 3E13 vg/kg dose in the MyPEAK-1 trial with no unexpected events or toxicities associated with study drug observed. Safety data from Cohort 1 were reviewed by an independent Data and Safety Monitoring Board, or DSMB, showing a safety and tolerability profile consistent with other AAV gene therapies at this dose. Accordingly, the DSMB recommended that Tenaya proceed with dose escalation to the 6E13 vg/kg dose, per protocol. Enrollment of Cohort 2 is underway. Tenaya has implemented several changes in the MyPEAK-1 protocol intended to support future development, including: Adding a baseline biopsy, increasing the total number of cardiac biopsies from two to three, and permitting more flexible timing of post-dose biopsies to help characterize TN-201 expression over time. Expanding eligibility to include participants who do not have an implantable cardioverter defibrillator device and to permit adults with either obstructive or nonobstructive forms of HCM to enroll. Increasing the potential number of total patients enrolled in the dose expansion portion of the clinical trial from nine to twenty-four adults. Tenaya plans to report initial data from Cohort 1 in December of this year. This readout is expected to focus on TN-201’s safety and tolerability, analyses of cardiac biopsy, as well as changes from baseline in cardiac biomarkers. The MyPEAK-1 clinical trial is also collecting data to understand TN-201’s effect on imaging biomarkers, heart function, exercise capacity, functional status, and patient quality of life. As part of Tenaya’s ongoing efforts to characterize the disease burden for children and adolescents with MYBPC3-associated HCM, Tingley recently presented data from a study conducted in partnership with the Sarcomeric Human Cardiomyopathy Registry (SHaRe): Of the nearly 1,800 MYBPC3-associated HCM individuals identified in SHaRe’s database, approximately 13% were diagnosed prior to age 18. The cumulative lifetime risk of severe events for MYBPC3-associated pediatric patients is very high, with 50% experiencing significant morbidity by age 40. Both adult and pediatric MYBPC3-associated HCM individuals have high rates of serious complications, such as heart failure and ventricular arrhythmias, highlighting the need for timely diagnosis, active monitoring and new genetic medicines that can have a meaningful impact on outcomes. These data were presented at the virtual HCM Society Scientific Sessions and are available in the Publications page of Tenaya’s website. Tenaya also continues to characterize the pediatric MYBPC3-associated HCM population through the MyClimb natural history study with more than 200 children and adolescents enrolled across 29 sites in USA, Canada, Spain, and the United Kingdom.