FDA Grants Fast Track Designation to GenSight for Optogenetic Therapy to Treat Retinitis Pigmentosa

The U.S. Food and Drug Administration granted Fast Track designation to GenSight Biologics’ GS030, which combines AAV2-based gene therapy with optogenetics to treat retinitis pigmentosa.

Photo: Bernard Gilly, co-founder and CEO of GenSight

Retinitis pigmentosa (RP) is a family of orphan genetic diseases caused by multiple mutations in numerous genes involved in the visual cycle. More than 100 genetic defects have been implicated. RP patients generally begin experiencing vision loss in their young adult years, with progression to blindness by age 40. RP is the most widespread hereditary cause of blindness in developed nations, with a prevalence of about 1.5 million people throughout the world. In Europe and the United States, about 350,000 to 400,000 patients suffer from RP, and every year between 15,000 and 20,000 new patients with RP lose sight. There is currently no curative treatment for RP.

“The Fast Track designation granted by the FDA to GS030 highlights the significant unmet need for a safe and effective treatment of all forms of retinitis pigmentosa,” said Bernard Gilly, co-founder and CEO of GenSight. “Following the publication of a promising first case report in Nature Medicine in June, and with more data from the PIONEER trial expected later this year, we are in a great position in our quest to provide a cutting-edge treatment for retinitis pigmentosa patients.”

Optogenetic therapies combine cellular expression of light-sensitive opsins with light stimulation using a medical device. GS030 uses an optimized viral vector (GS030-DP) to express the light-sensitive opsin ChrimsonR in retinal ganglion cells and proprietary light-stimulating goggles (GS030-MD) to project the right wavelength and intensity of light onto the treated retina. Granted Orphan Drug designation in the United States and Europe, GS030-DP is administered via an intravitreal injection.

PIONEER, a phase 1/2 first-in-human, multi-center, open-label dose-escalation clinical trial to evaluate the safety and tolerability of GS030 in 12-18 subjects with late-stage RP, is being conducted in three centers across the United Kingdom, France, and the United States. Eligible patients in the first three cohorts are those affected by end-stage non-syndromic RP with no light perception (NLP) or light perception (LP) levels of visual acuity. The extension cohort will include patients with hand motion (HM) and counting fingers (CF) levels of visual acuity.

A case report of a patient, who was treated with a low dose (5e10 vg) of the gene therapy and subsequently experienced visual recovery, was published in Nature Medicine in June 2021. The Data Safety Monitoring Board recently recommended that the highest dose of the gene therapy (5e11 vg) be used for the extension cohort in the PIONEER trial. Additional interim results may be released in Q4 2021, and results of all treated patients with one year follow-up data are expected in 2023.

Fast Track is a process intended to facilitate the development and expedite the review of drugs for the treatment of serious conditions where there is an unmet medical need. The purpose is to get important new drugs to the patient earlier. Drugs that receive Fast Track designation may be eligible for more frequent communications and meetings with FDA to discuss the drug’s development plan, including the design of the proposed clinical trials, and ensure collection of appropriate data needed to support drug approval. Drugs with Fast Track designation may also qualify for Accelerated Approval, Priority Review or Rolling Review of New Drug Applications (NDA) or Biologic License Applications (BLA) if relevant criteria are met.

Author: Rare Daily Staff