Clinical diagnosis of CPVT, based on documented history of polymorphic or bidirectional non-sustained ventricular tachycardia with exercise or ventricular ectopy in a pattern consistent with CPVT on EST.
Central Screening laboratory determination of a RYR2 variant that is pathogenic or likely pathogenic for CPVT.
Documented history of life-threatening ventricular arrhythmic event defined as: survived sudden cardiac arrest, sudden cardiac arrest with appropriate implantable cardioverter defibrillator (ICD) shock, arrhythmic syncope, or sustained ventricular tachycardia (30 seconds or more) with or without ICD shock.
On stable dose (defined as no change in dose by more than 50% for at least 1 month prior to Screening) of standard-of-care therapy defined as a beta-blocker and/or flecainide.
Documented prior history of EST demonstrating a ventricular arrythmia score (VAS) score of ≥ 2.
For the first 2 participants in each cohort only: a properly functioning ICD device in place. Following review of data from Cohorts 1 and 2, the Data Safety and Monitoring Board (DSMB) will determine if this criterion is required for participants in Cohort 3.
Must be up to date with meningococcal vaccination per national guidelines or willing to receive meningococcal vaccine to achieve this.
You may not be if
Abnormal liver function: gamma-glutamyl transferase (GGT) \> 1.5 × upper limit of normal \[ULN\] or total bilirubin \> ULN).
Abnormal renal function defined by estimated glomerular filtration rate \< 60 milliliter /minute (mL/min)/1.73-square meter (m\^2) using Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) Formula.
Clinically significant abnormalities of coagulation including international normalized ratio or activated partial thromboplastin time \> 1.2 × ULN or platelets \< 150,000 cells/cubic millimeter (mm\^3).
Potential concomitant cardiomyopathy or inherited arrhythmia as evidenced by pathogenic or likely pathogenic mutation other than RYR2 obtained on cardiac panel during Screening.
Current or prior treatment with an approved or investigational gene transfer drug.
Exposure to another investigational drug within 90 days prior to Screening or 5 half-lives since last administration, whichever is longer.
Contraindication or unwillingness to receive required immunosuppression regimen.
Body mass index ≥ 30 kilograms per square meter (kg/m\^2).
Clareo Health | A Study of SGT-501 Gene Therapy in Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
