Dr. Albert Maguire checks the eyes of Misa Kaabali, 8, at the Children’s Hospital of Philadelphia. (AP Photo/Bill West)

The U.S. Food and Drug Administration’s Cellular, Tissue and Gene Therapies Advisory Committee yesterday endorsed the first gene therapy for patients with Leber congenital amaurosis, also called Biallelic RPE65-mediated inherited retinal disease.  

The vote was 16 to 0 in favor of the treatment, voretigene neparvovec from Spark Therapeutics.

 “This Advisory Committee decision is a milestone achievement for inherited retinal disease research and the patient communities,” Dr. Stephen Rose, Chief Research Officer, Foundation for Fighting Blindness, told Drug Discovery & Development via email.  “The Foundation Fighting Blindness strongly endorses the committee’s recommendation that the treatment be approved.  Not only will the treatment be life-changing for people with RPE65 mutations, such approval will help propel additional ocular gene therapies forward; potential treatments that could help millions of people see.”

The treatment basically replaces a faulty gene with a working one. The investigational treatment delivers functional copies of the RPE65 gene directly into the retina via injection. 

 If approved, voretigene neparvovec has the potential to be the first FDA-approved gene therapy for the eye—and for any inherited disease.

“There currently are no pharmacologic treatment options for people living with RPE65-mediated IRD, who in most cases progress to complete blindness,” said Principal Investigator Albert M. Maguire, M.D., professor of ophthalmology at the Scheie Eye Institute at the University of Pennsylvania’s Perelman School of Medicine and attending physician in the Division of Pediatric Ophthalmology at Children's Hospital of Philadelphia, in a statement.

The recommendation is based on voretigene neparvovec’s clinical development program, which includes the first completed randomized, controlled Phase III gene therapy clinical trial ever conducted for a genetic disease.

The safety and efficacy of voretigene neparvovec were assessed in two open-label Phase I trials, which continue to follow participants who received the treatment between 2007 and 2012, and one open-label, randomized, controlled Phase III trial.

In the original Phase III intervention group, participants aged four to 44 years on average maintained the functional vision and visual function improvements demonstrated 30 days after administration through their last annual follow-up visit, as measured by bilateral multi-luminance mobility test (MLMT) score change and full-field light sensitivity threshold testing.

Data from a cohort of the Phase I clinical trial, in which the treatment was administered to the second previously uninjected eye, showed similarly maintained mean improvements.

As part of the Biologics License Application (BLA) to FDA, Spark also submitted the results of two Phase I clinical trials, a natural history study and a MLMT validation study.

The FDA isn’t obligated to follow the recommendations of its advisory committees, but it usually does.  Voretigene neparvovec is under Priority Review with the FDA and has a PDUFA date of January 12, 2018.

If approved, the treatment would be marketed under the name Luxturna.