FDA Approves Spark’s Gene Therapy to Treat Patients with a Rare Form of Inherited Vision Loss

Rare Daily Staff

The U.S. Food and Drug Administration said it approved Luxturna, Spark Therapeutics’ gene therapy to treat an inherited form of vision loss that may result in blindness and the first gene therapy approved in the United States that targets a genetic disease.

The approval came nearly a month ahead of the expected date for an FDA decision and followed a unanimous recommendation for approval from an agency advisory panel in October.

“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. “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.”

The attention on Luxturna will now turn to its price tag. There has been wide speculation that Spark will set a price as high as $1 million per treatment. While the company has discussed broad issues around its approach to pricing, and suggested several models would support such a price, it has not indicated specific pricing for the therapy.

Luxturna is approved for the treatment of patients with confirmed biallelic RPE65 mutation-associated retinal dystrophy that leads to vision loss and may cause complete blindness in certain patients. The condition affects about 1,000 to 2,000 patients in the United States. The RPE65 gene provides instructions for making an enzyme that is essential for normal vision. There are currently no approved pharmacologic treatment options for IRD due to biallelic RPE65 gene mutations.

Luxturna works by delivering a normal copy of the RPE65 gene directly to retinal cells. These retinal cells then produce the normal protein that converts light to an electrical signal in the retina to restore patient’s vision loss. Luxturna uses a naturally occurring adeno-associated virus, which has been modified using recombinant DNA techniques, as a vehicle to deliver the normal human RPE65 gene to the retinal cells to restore vision.

The safety and efficacy of Luxturna were established in a clinical development program with a total of 41 patients between the ages of 4 and 44 years. All participants had confirmed biallelic RPE65 mutations. The primary evidence of efficacy of Luxturna was based on a late-stage study with 31 participants by measuring the change from baseline to one year in a subject’s ability to navigate an obstacle course at various light levels. The group of patients that received Luxturna demonstrated significant improvements in their ability to complete the obstacle course at low light levels as compared to the control group.

The most common adverse reactions from treatment with Luxturna included eye redness (conjunctival hyperemia), cataract, increased intraocular pressure and retinal tear.

Spark is receiving a Rare Pediatric Disease Priority Review Voucher, which is transferable and allows the bearer to have the FDA accelerate the review of a marketing application for a new drug to six months from 10 months. Ultragenyx sold a PRV earlier this week for $130 million.

December 18, 2017