A Study to Evaluate Safety, Tolerability, and Efficacy of AB-1009 Gene Therapy (GAA Gene) in Adult Participants With Late Onset Pompe Disease (PROGRESS-GT LOPD)

Exclusion Criteria

• •1. Severe cardiomyopathy, defined as left ventricular ejection fraction (LVEF) \<40% or New York Heart Association (NYHA) functional class 3 or above;
• •2. Require invasive mechanical ventilation, or rely on noninvasive ventilation during the day;
• •3. Intolerance to ERT or investigator-assessed intolerance to ERT, prior experience of serious ERT-related infusion-associated reactions (IARs);
• •4. Have known intrinsic liver diseases, including hepatitis, HIV-related liver disease, prior diagnosis of portal hypertension, splenomegaly, hepatic encephalopathy, severe fatty liver, cirrhosis or liver fibrosis ≥stage 2, ultrasound-identified liver neoplasms, or laboratory tests suggesting elevated alpha-fetoprotein. Patients with liver function tests including ALT or AST \>3× upper limit of normal (ULN) or any total bilirubin above ULN during screening will also be excluded;
• •5. Prior or ongoing medical condition(s), physical finding(s), assessment findings, or laboratory abnormality that, in the investigator's opinion, would impact participant's safety and compliance with the study procedures.
• •6. Have received gene therapy prior to screening;
• •7. Have received any systemic immunosuppressants (except inhalation or topical use) other than glucocorticoids or investigator-recommended immunosuppressants 30 days prior to screening through completion of screening, and/or known intolerance to immunosuppressants such as glucocorticoids;
• •8. Use of investigational drugs or drugs that could affect this study as evaluated by the investigator within 30 days prior to screening through completion of Week 52 or within 5 half-lives of the investigational drug (whichever is longer);
• •9. Have received any vaccine within 30 days prior to dosing;