The study will evaluate safety and efficacy of gene therapy in spinal muscular atrophy Type 1 (SMA1) patients. SMA is caused by low levels of the survival motor neuron (SMN) protein, and affects all muscles in the body. There is no effective treatment for SMA and current drug therapy has been unsuccessful in stabilizing or reversing this disease. Only supportive care is currently possible.~Open-label, dose-escalation clinical trial of EXG001-307 injected intravenously through a peripheral limb vein. Short-term safety will be evaluated over a 1.5 year period. Patients will be tested at baseline and return for follow up visits on days 14, 21, 30, followed by once every month through 12 months post dose, and then every three months through a year and a half post infusion. Unscheduled visits may occur if the PI determines that they are necessary.~The primary analysis for efficacy will be assessed when all patients reach 18 months of age (a database lock will be performed at the time point at which all patients reach 18 months of age). A follow-up safety analysis will be completed at the time point at which the last patient reaches 18 months of age after post-dose.~Upon completion of the 1.5-year study period, patients will be monitored annually as per standard of care for up to 5 years.
The purpose of this trial is to evaluate safety and efficacy of intravenous delivery of EXG001-307 as a treatment of spinal muscular atrophy Type 1 (SMN1).