AveXis Phase 3 Trial Studying Gene Therapy for SMA Type 1 Now Enrolling Infants

A Phase 3 clinical trial to evaluate the safety and efficacy of an investigational gene replacement therapy by AveXis is now recruiting infants with spinal muscular atrophy (SMA) type 1.

The trial of AVXS-101 seeks patients younger than six months of age. Participants must have a genetic mutation analysis confirming SMA type 1 diagnosis, according to a news release from the Muscular Dystrophy Association.

AVXS-101 is designed to specifically deliver the fully functional human SMN gene to motor neurons, which SMA patients lack. This will restore normal levels of survival motor neuron (SMN) protein in these nerve cells, allowing them to properly control muscle activity and improve strength and function.

Results of a Phase 1 study (NCT02122952) showed that the motor functions of babies with SMA type 1 show clinically meaningful improvements after one single intravenous infusion. Eight of the 15 infants treated with AVXS-101 were able to sit without assistance and two could crawl, stand or walk independently — all abilities never seen in untreated SMA infants.

The U.S. Food and Drug Administration (FDA) has granted AVXS-101 Orphan Drug Designation to treat all types of SMA. AVXS-101 has also received Breakthrough Therapy Designation and Fast Track Designation to treat SMA Type 1. Both will speed up the drug’s clinical development and potential approval.

The STR1VE study (NCT03306277) is an open-label Phase 3 trial to evaluate the impact of AVXS-101 on children’s development and overall survival. It will likely include 15 infants with genetically confirmed non-functional SMN1 gene, but with one or two copies of the SMN2 gene. The study — to be conducted at clinics in California, Colorado, Illinois, Maryland, New York, Ohio and Oregon — will evaluate patients’ capacity to sit by themselves at 18 months of age, as well as their ability to breathe without additional support upon receiving one injection of AVXS-101.

All required clinical visits, tests and additional treatments will be provided to participants at no cost, as well as travel assistance for families who don’t live near any of the study sites. For additional information on the STR1VE trial, please visit the study website or the study registry page. To participate, contact the trial coordinator at the nearest site.