X-Linked Retinitis Pigmentosa Gene Therapy Improves BCVA
Interim data from the phase 2 Skyline trial demonstrated a 62.5% response rate.
The RPGR-targeted gene therapy AGTC-501 improved visual sensitivity in patients with X-linked retinitis pigmentosa, according to interim data from the phase 2 Skyline trial (NCT04850118).
“The meaningful response rate in visual sensitivity seen in this interim Skyline data is very encouraging, as are the favorable safety data,” investigator Robert Sisk, MD, FACS, FASRS, director, Pediatric Vitreoretinal Surgery and Ophthalmic Genetics, Cincinnati Children’s Hospital and Cincinnati Eye Institute, said in a statement. “Patients with XLRP have no FDA-approved options to treat this devastating disease and we believe the results presented today show great promise to provide outcomes that are truly meaningful and potentially life-changing to patients.”
The recombinant adeno-associated virus vector (AAV) gene therapy by Applied Genetic Technologies Corporation yielded a 62.5% response rate in best-corrected visual acuity (BCVA) as measured by MAIA microperimetry in the higher dose group and a 25% response rate in the lower dose group in multiple patients 3 months after dosing. Investigators also found that mean visual sensitivity of the macula increased as well as the area of the macula with visual sensitivity. Over half of patients showed improvements in light levels passed, improved speed and/or reduced errors in the mobility maze.
This data, from an interim analysis, includes 13 of 14 male pediatric and adults in the low and high dose groups. The phase 2 trial follows the previous phase 1/2 trial that found that responses were durable through 12 months. AGTC-501 continues to be well-tolerated, with mostly mild-to-moderate adverse events (AEs). The phase 2 trial participants were younger than those in comparable dose groups from the phase 1/2 trial and had better BCVA and mean visual sensitivity, possibly leading to less pronounced vision improvements.
“We are incredibly excited by the compelling interim results seen in the Skyline trial, including strong safety data and robust improvements in visual sensitivity with a clear difference between the two dose groups. These results add to the growing body of evidence supporting the best-in-class potential of AGTC-501 for the treatment of XLRP,” said Sue Washer, President and Chief Executive Officer of AGTC. “We believe that if we achieve similar results in the Vista Phase 2/3 clinical trial, we will have a broad and compelling body of data to support the submission of a BLA to the FDA, and to enable a differentiated and highly competitive product profile.”
