Rare Eye Disease Treatment Shows Promise in Early Trial

Children found to greatly benefit from gene therapy for Leber congenital amaurosis.

A phase 1 clinical trial showed that children reaped the greatest benefits from gene therapy for the rare eye disease Leber congenital amaurosis (LCA) or severe early childhood onset retinal degeneration (SECORD).

Gene therapy has shown promise in treating rare genetic eye diseases such as LCA because of mutations in the RPE65 gene. In a recent study, researchers developed a novel quantitative visual field analytic tool to more accurately measure the visual field.

A study published in Ophthalmology enrolled 8 adults and 4 children between 6- and 39-years-old. Surgeons used a viral vector to insert a normal copy of the mutated RPE65 into the retinal cells of the patient’s eye to restore retinal function.

“Treatments for childhood blindness have profound effects because these children have their whole lives ahead of them,” said study co-author David Wilson, MD. “Demonstrating the effectiveness of gene therapy in the eye will have broad implications for the rest of medicine as well.”

The results of the study showed that subretinal injection into the participant’s poorer-seeing eye to treat LCA and SECORD was considered safe. Nine out of 12 patients experience improved visual acuity or in visual field.

“I am very optimistic about these study findings,” said senior study author Richard Weleber, MD. “Gene replacement therapy has proven to be the most promising method to halt progression of childhood blindness due to single gene defects. The eye is a perfect platform for gene therapy because we can treat one eye to see how it responds compared to the other eye.”