MyoAAV4A-Dual-Pull

MyoAAV4A-Dual-Pull is an experimental gene therapy designed for the treatment of Glycogen Storage Disease type IIIa (GSD IIIa). It utilizes a myotropic adeno-associated virus (AAV) vector, specifically the MyoAAV4A capsid, which is engineered for high-efficiency transduction of skeletal and cardiac muscle. The vector delivers a transgene encoding pullulanase, a bacterial enzyme that serves as a functional replacement for the deficient endogenous glycogen debranching enzyme. Expression is controlled by an immunotolerizing dual promoter intended to drive transgene activity in both muscle and liver while minimizing immune responses. Preclinical studies in mouse and dog models have demonstrated the therapy's ability to reduce pathological glycogen accumulation in target tissues, though immune-mediated toxicities in adult dogs suggest the need for optimized immunosuppressive regimens.