FDA Approves Gene Therapy for Rare Vision Loss Disease

Today, the FDA approved Luxturna (voretigene neparvovec-rzyl) to treat pediatric and adult patients with a rare form of inherited vision loss. This is the first gene therapy approved to target the underlying genetic mutations that causes the disease, according to a press release.

Luxturna is indicated to treat patients with confirmed biallelic RPE65 mutation-associated retinal dystrophy that results in vision loss and can progress to blindness, according to the FDA.

“Today’s approval marks another first in the field of gene therapy—both in how the therapy works and in expanding the use of gene therapy beyond the treatment of cancer to the treatment of vision loss—and this milestone reinforces the potential of this breakthrough approach in treating a wide-range of challenging diseases,” said FDA Commissioner Scott Gottlieb, MD. “The culmination of decades of research has resulted in three gene therapy approvals this year for patients with serious and rare diseases. I believe gene therapy will become a mainstay in treating, and maybe curing, many of our most devastating and intractable illnesses.”

Hereditary retinal dystrophics include a number of genetic retinal disorders linked to progressive vision loss caused by mutations in 1 or more of 220 genes, according to the release. Specifically, bialllelic RPE65 mutation-associated retinal dystrophy affects up to 2000 Americans.

The FDA reported that the RPE65 gene codes instructions for an enzyme that is crucial for normal vision. Mutations can block the visual cycle and lead to impaired vision. These patients typically experience symptoms during childhood or adolescence, and typically develop blindness.

Luxturna harnesses an adeno-associated virus to deliver a normal RPE65 gene to retinal cells. This process causes the cells to produce a normal version of a protein that converts light into an electrical signal, which restores vision, according to the FDA. The gene therapy is administered via subretinal injection.

“The approval of Luxturna further opens the door to the potential of gene therapies,” said Peter Marks, MD, PhD, director of the FDA Center for Biologics Evaluation and Research. “Patients with biallelic RPE65 mutation-associated retinal dystrophy now have a chance for improved vision, where little hope previously existed.”

The FDA advises that Luxturna should only be administered to patients who have retinal cells and the treatment should be administered in each eye on different days, with 6 or more days between procedures, according to the release. During treatment, patients should also receive prednisone to dampen immune reactions to the injection.

The safety and efficacy of the drug were explored in 41 patients aged 4 to 44 years who had confirmed biallelic RPE65 mutations. The primary efficacy was based on a phase 3 clinical trial that included 31 patients and assessed their ability to navigate an obstacle course at various lights. The researchers found that those treated with Luxturna had significant improvements in their ability to make it through the course at low light levels compared with control patients, according to the release.

Common adverse events included eye redness, cataract, increased intraocular pressure, and retinal tear, the FDA reported.

Previously, Luxturna was granted priority review, breakthrough therapy, and orphan drug designations.

“We’re at a turning point when it comes to this novel form of therapy and at the FDA, we’re focused on establishing the right policy framework to capitalize on this scientific opening,” Dr Gottlieb said. “Next year, we’ll begin issuing a suite of disease-specific guidance documents on the development of specific gene therapy products to lay out modern and more efficient parameters — including new clinical measures — for the evaluation and review of gene therapy for different high-priority diseases where the platform is being targeted.”