Selected Inclusion Criteria: * Adults with a clinical diagnosis of ACM meeting the 2010 revised Task Force Criteria (TFC) * Genetic testing documenting a pathogenic or likely pathogenic variant in PKP2 * Frequent premature ventricular complexes (PVCs) * Implantable cardioverter-defibrillator (ICD) implantation ≥ 12 weeks prior to the pre-screening MRI * Left ventricular ejection fraction ≥ 40% Selected Exclusion Criteria: * Evidence of variant(s) in addition to PKP2 that meets the standard criteria to be considered pathogenic or likely pathogenic for ACM * Other cardiac abnormalities as specified in the protocol * New York Heart Association Functional Class IV at the time of consent * History of prior gene transfer therapy