FDA Grants Axovant Gene Therapies Rare Pediatric Disease Designation for GMI Therapy

Rare Daily Staff

The U.S. Food and Drug Administration has granted Rare Pediatric Disease designation to Axovant Gene Therapies’ gene therapy for the treatment of GM1 gangliosidosis.

GM1 Gangliosidosis is a progressive and fatal pediatric lysosomal storage disorder caused by mutations in the GLB1 gene leading to impaired production of the β-galactosidase enzyme. Currently, there are no approved treatment options for GM1 Gangliosidosis.

Axovant’s AXO-AAV-GM1 an AAV9-based gene therapy delivered via a single intravenous administration that is in phase 1/2 development for GM1 gangliosidosis.

It delivers a functional copy of the GLB1 gene with the goal of restoring β-galactosidase enzyme activity for the treatment of GM1 gangliosidosis. Preclinical studies in murine and a naturally-occurring feline model of GM1 gangliosidosis have supported AXO-AAV-GM1’s ability to improve β-galactosidase enzyme activity, reduce GM1 ganglioside accumulation, improve neuromuscular function, and extend survival.

“Receiving Rare Pediatric Disease designation in addition to the previously granted Orphan Drug designation for AXO-AAV-GM1 highlights the importance of expediting a therapy for GM1 Gangliosidosis, a progressive, fatal, pediatric disease with no approved treatment options,” said Sean O’Bryan, senior vice president of regulatory affairs and quality. “AXO-AAV-GM1 is the first gene therapy to enter clinical trials for GM1 gangliosidosis and has the potential to provide meaningful clinical benefit to both type 1 and type 2 patients.”

Axovant is on-track to report 6-month Stage 1 data from the low dose juvenile cohort (type 2) by the fourth quarter of 2020, and expects to initiate the high dose cohort, which includes infantile (type 1) and juvenile (type 2) patients before the end of the year.

The FDA grants Rare Pediatric Disease designation for serious or life-threatening diseases with manifestations in individuals aged from birth to 18 years, including access to the FDA’s expedited review and approval process. The designation makes rivipansel eligible for a Rare Pediatric Disease Priority Review voucher upon approval of the therapy by the FDA.

The vouchers can be used to reduce the time of an FDA new drug approval review to six months from ten months. The vouchers are potentially lucrative because they are transferable. Most recently, Sarepta sold its priority review voucher to Vifor Pharma $111 million in February 2020.

The program was due to expire at the end of September with a drug that had been granted RPD designation prior to that date still eligible to receive the voucher if it receives final FDA approval before September 30, 2022.

On September 30, 2020, Congress provided a short-term extension of the Rare Pediatric Disease Priority Review Voucher Program. According to the current statutory sunset provisions, after December 11, 2020, FDA may only award a voucher for an approved rare pediatric disease product application if the sponsor has rare pediatric disease designation for the drug, and that designation was granted by December 11, 2020. After December 11, 2022, FDA may not award any rare pediatric disease priority review vouchers.

Requests for rare pediatric disease designation submitted within two weeks of a request for fast track designation or orphan drug designation are entitled to a 60-day review. Requests for rare pediatric disease designation not submitted with a request for fast track designation or orphan drug designation are reviewed in a timely manner, however, the 60-day response time does not apply. Today, October 9, 2020, is the last business day that is not less than 60 days prior to December 11, 2020. The Offices of Orphan Products Development and Pediatric Therapeutics will continue to review all rare pediatric disease designation requests but said it cannot commit to providing a response to requests received after October 9, 2020.