Spark’s gene therapy Luxturna secures FDA approval for rare form of blindness

The investigational adeno-associated viral (AAV) vector gene therapy has been approved as a one-time gene therapy for confirmed Biallelic RPE65 mutation-associated retinal dystrophy.

Patients having RPE65-mediated inherited retinal disease frequently experience night blindness (nyctalopia) and in most of the cases, the disease is known to result in complete blindness.

Luxturna’s approval was based on a phase 3 trial in 34 patients with confirmed biallelic RPE65 mutations. The late-stage trial saw the gene therapy successfully maintain the functional vision and improve visual functions of the enrolled patients, 30 days after its administration.

It was also found to have improved the ability of patients in navigating obstacles in dim light conditions by 93%.

Luxturna has now become the first pharmacologic treatment for an inherited retinal disease (IRD) and also the first AAV to be approved in the US.

FDA commissioner Scott Gottlieb said: “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.

“The culmination of decades of research has resulted in three gene therapy approvals this year for patients with serious and rare diseases.”

The gene therapy should be given to only patients with mutations on both copies of the RPE65 gene who have enough viable retinal cells as determined by their treating physicians.

Intended to be administered intravenously (IV) or injected into specific tissue, Luxturna produces viral vector particles with the correct copy of the RP65 gene to retinal cells, thereby restoring their ability to generate the deficient enzyme.

Spark Therapeutics CEO Jeffrey Marrazzo said: “This one-time gene therapy for an inherited disease represents a first-of-its-kind breakthrough that may lay the groundwork for the development of gene therapies for other conditions that are not adequately addressed today.”

Spark Therapeutics plans to manufacture Luxturna at its manufacturing facility in West Philadelphia.

Image: Luxturna (voretigene neparvovec-rzyl) product vial. Photo: courtesy of Spark Therapeutics, Inc.