AveXis, Inc., announced that its Phase 1 clinical trial of its proprietary gene therapy candidate, AVXS-101, for the treatment of spinal muscular atrophy (SMA) Type 1 has now completed patient enrollment.
Fifteen young patients, diagnosed before age six months and with two copies of the SMN2 backup gene, as determined by genetic testing, are taking part in the open-label, dose-escalation trial, and will be assigned to one of two dosing groups:
- A cohort of at least three patients receiving 6.7 X1013 vg/kg doses, and ages six to seven months at the time of dosing
- A cohort of at least 12 patients receiving 2.0 X1014 vg/kg doses, and ages 1 year to eight months at the time of dosing
The study’s primary outcome is the safety and tolerability of AVXS-101; the secondary outcome is efficacy, as defined by the time from birth to the first “event” (defined as death or requiring at least 16 hours a day of ventilation support for 14 consecutive days for reasons other than acute reversible illness or surgery).
Exploratory outcome measures will also be taken, including motor skill or function testing assessed by the Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND).
Each participant will receive a one-time dose of AVXS-101 administered through intravenous (IV) injection during the course of one hour. Patients will remain at the clinical trial site for 48 hours after dosing for monitoring before discharge, with weekly follow-up evaluations continuing for one month after dosing and followed by monthly evaluations for the next 23 months.
“We are pleased to have reached this important initial clinical milestone in our effort to bring AVXS -101 to patients who suffer from SMA Type 1, a devastating disease for which there are currently no FDA-approved therapies,” Sean Nolan, AveXis president and CEO, said in a press release. “The data from this initial trial will inform future clinical studies in Type 1 and potentially other types of SMA. We look forward to reviewing the data from this study over the coming year as we continue the development of AVXS-101.”
Approximately one in every 10,000 newborns are diagnosed with spinal muscular atrophy. SMA Type 1 is the most aggressive form the genetic disease can take, and over 90 percent of babies born with the disease will likely need permanent ventilation support before age 2. SMA is a neuromuscular disease marked by the loss of motor neurons, which leads to progressive muscle weakness and, eventually, paralysis. SMA is triggered by a defect in the SMN1 gene that codes SMN, a protein necessary for motor neuron survival.