Open-label, Dose Escalation Study of Safety and Preliminary Efficacy of TN-401 in Adults With PKP2 Mutation-associated ARVC

Inclusion Criteria: * PKP2 mutation (pathogenic or likely pathogenic) * Arrhythmogenic Right Ventricular Cardiomyopathy as defined by the 2010 revised Task Force Criteria * Left Ventricular Ejection Fraction ≥50% * Functioning Implantable Cardiac Defibrillator with remote integration capabilities at least 9 months prior to Screening * NYHA Functional Class I, II, or III * Frequent premature ventricular contractions (PVCs) Exclusion Criteria: * Ventricular tachycardia (VT) ablation within 6 months of Screening or planned VT ablation within 6 months after Screening * High AAV9 neutralizing antibody titer * Prior myocardial infarction * Right Ventricular Heart Failure * Class IV Heart Failure * Clinically significant renal disease * Clinically significant liver disease