Novartis’ Luxturna has been approved by regulators in Europe to treat a rare inherited condition that causes sight loss.

The European Commission has given its seal of approval for use of the one-time gene therapy to treat patients with vision loss due to a genetic mutation in both copies of the RPE65 gene, if they have enough viable retinal cells.

Luxturna (voretigene neparvovec) works by delivering a normal copy of the RPE65 gene directly to retinal cells, which then produce the normal protein that converts light to an electrical signal in the retina to restore vision loss.

The therapy 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.

In a Phase III clinical trial vision improvement was recorded as early as 30 days following treatment with Luxturna. Vision improved by one or more light levels for 90% of patients treated and 65% were able to successfully navigate the an obstacle at the lowest light level after one year.

The approval is “momentous for patients given that there have been no pharmacological treatment options to date to treat this form of LCA [Leber congenital amaurosis]," said Christina Fasser, president of Retina International.

"Access to this treatment has the potential to reduce the substantial physical, emotional and financial burden this disease has on patients and their families."

Luxturna, to which Novartis picked up rights outside the US from Spark Therapeutics early this year, was approved by FDA under priority review in December last year.