Spark Therapeutics received a landmark FDA approval as its inherited retinal disease drug Luxturna (voretigene neparvovec-rzyl), became the first gene therapy ever approved for an inherited disease.
Luxturna is a one-time gene therapy indicated for the treatment of patients with confirmed biallelic RPE65 mutation-associated retinal dystrophy. The drug is the first FDA-approved gene therapy for a genetic disease, the first and only pharmacologic treatment for an inherited retinal disease, and the first adeno-associated virus vector gene therapy approved in the United States.
The first-of-its-kind approval may lay the groundwork for the development of gene therapies for other conditions.
“I think one of the really exciting aspects of today's approval is that there are over 220 genes involved in vision, and until today there were no treatments for any forms of inherited retinal blindness,” Katherine High, MD, Co-founder, President and Chief Scientific Officer at Spark Therapeutics said in an interview with Eyewiretoday.com. “The approval of Luxturna signifies that there is a pathway forward for turning genes into medicines.”
Luxturna should only be administered to patients with mutations on both copies of the RPE65 gene who have sufficient viable retinal cells as determined by their treating physicians. Luxturna is administered by subretinal injection to each eye on separate days within a close interval, but no fewer than 6 days apart.
“Luxturna is a gene therapy product that is delivered into the sub-retinal space, and it supplies a normal copy of a gene called RPE 65, which is defective in some cases of inherited retinal dystrophy. This disease affects, we think, around 1,000 to 2,000 people in the United States, and they may present with visual problems very early in life, in infancy, or they may present later during childhood, but eventually most of these patients will progress to blindness,” Dr. High said. “In a trial that was sponsored by Spark Therapeutics, a randomized control trial, we were able to show that the sub-retinal administration of this gene therapy vector resulted in improvements in the ability to navigate independently as judged by a mobility test that was developed as an end point for this trial. And we also showed improvement in other tests of visual and retinal function, including full field light sensitivity, and visual fields.”
Philadelphia-based Spark Therapeutics said it will not announce the therapy’s price until January, but analysts predict the treatment will be priced around $1 million. Spark stated in a news release that it is committed to ensuring eligible patients have access to Luxturna and will offer patient support services for eligible patients.
Luxturna is expected to be available to select retina specialists late in the first quarter of 2018. The gene therapy will be administered at selected treatment centers in the US by select retinal surgeons, who will receive surgical training provided by Spark Therapeutics on the administration procedure.
“During the more than 12 years of innovative research with dedicated collaborators near and far, I’ve witnessed the dramatic improvement in vision in many patients who would have otherwise lost their sight,” Jean Bennett, the F.M. Kirby Professor of Ophthalmology in the Perelman School of Medicine at the University of Pennsylvania and Penn’s Scheie Eye Institute, said in a company news release. “I believe that the success of the Luxturna clinical development program will pave the way for the development of other gene therapies, that may help the millions of patients with genetic diseases who currently have limited or no treatment options.”
Luxturna was approved by FDA under priority review and previously received orphan drug and breakthrough therapy designations from the FDA. Spark Therapeutics’ Marketing Authorization Application for Luxturna is currently under review with the European Medicines Agency. Luxturna also has received orphan product designations from EMA.