AveXis’ SMA Type 1 Gene Therapy Granted Speedier Review in Japan

AVXS-101 has been awarded the SAKIGAKE designation in Japan for the treatment of spinal muscular atrophy (SMA) type 1. This designation will speed the therapy’s development and review process and allow faster license applications in Japan.

AVXS-101, the lead product candidate of AveXis, is a gene therapy under development for the treatment of SMA type 1 and SMA type 2. It delivers a normal copy of the SMN1 gene to the motor neurons of patients with SMA who carry a faulty SMN1. The therapy is intended to re-establish the production of functional SMN1 in motor neurons, avoiding their degeneration and preventing further muscle weakening and wasting.

The designation “underscores the agreement by the Japanese government that there is an urgent need for a new therapeutic approach to treat Japanese patients diagnosed with SMA Type 1, and allows for enhanced discussions between AveXis and the agency to potentially expedite the timeline for approval of AVXS-101,” Sean Nolan, president and CEO of AveXis, said in a press release.

Japan’s Ministry of Health, Labour and Welfare announced the SAKIGAKE designation for AVXS-101 based on data from the Phase 1 clinical trial (NCT02122952). That trial addressed the safety and effectiveness of a one-time intravenous injection of AVXS-101 in 15 type 1 SMA infants, enrolled before they were 6 months old. Two doses, high and low, were evaluated.

The data revealed that all children were event-free at age 20 months — compared to a natural history that gives only 8 percent of type 1 children such a chance at that age — and most of the high-dose patients could sit unassisted, be fed orally and speak. Nine children were able to roll over at 20 months, and two could walk independently.

Based on the trial results, the U.S. Food and Drug Administration (FDA) awarded AVXS-101 a breakthrough therapy designation in July 2016 and the European Medicines Agency (EMA) granted AVXS-101 access to its Priority Medicines (PRIME) program in January 2017.

Similarly to these two designations, SAKIGAKE provides AVXS-101 therapy certain benefits intended to shorten the pre-market review period. This designation is attributed only to innovative medical products that meet specific criteria, including high severity of the intended indication, as is the case for SMA.

The FDA also has granted AVXS-101 orphan drug designation for the treatment of all types of SMA, as well as fast track designation for the treatment of SMA type 1.

AveXis is currently enrolling infants with SMA type 1 in the U.S. for its Phase 3 trial, STR1VE (NCT03306277), and expects to start a Phase 3 clinical trial in Europe in May. The STR1VE-EU trial (NCT03461289) is expected to include up to 30 children younger than 6 months with type 1 SMA.

The company also is recruiting children for a Phase 1 trial called STRONG (NCT03381729) that will test a high dose and a low dose of AVXS-101 for the treatment of SMA type 2. During this trial, patients will receive a one-time injection into the spinal canal.

“We look forward to continuing to work closely with the Japanese authority as well as regulatory authorities around the globe in our effort to bring this gene therapy to SMA patients and their families as safely and efficiently as possible,” said James L’Italien, chief regulatory and quality officer of AveXis.