The Phase 2/3 VISTA trial for AGTC-501 in XLRP is expected to begin in in the first half of 2024
Beacon Therapeutics Holdings Limited announced the presentation of 12-month interim safety and efficacy results for the Phase 2 SKYLINE trial in patients with X-linked retinitis pigmentosa (XLRP) at the 47th Annual Macula Society Meeting in Palm Springs, California.
The data were presented by Mark Pennesi, MD, PhD, FARVO, director of Ophthalmic Genetics at the Retina Foundation in Dallas, Texas, and professor of Ophthalmology and Professor of Molecular and Medical Genetics, Paul H. Casey Ophthalmic Genetics Division at the Casey Eye Institute, Oregon Health and Science University. His presentation was titled “Subretinal AGTC-501 Gene Therapy for XLRP: 12-month Interim Safety & Efficacy Results of the Phase 2 SKYLINE Trial.”
According to the company’s news release,1 12-month data from males with XLRP demonstrated a response rate of 63% in study eyes treated with a high dose (6.8 E+11 vg/eye) of AGTC-501. A "response rate" was defined as an improvement in retinal sensitivity, as assessed by microperimetry, of at least 7 decibels (dB) in at least 5 loci.
In his presentation, Pennesi noted that response rates in study eyes treated with a low dose (7.5 E+10 vg/eye) of AGTC-501 were similar to the untreated fellow eyes in the high dose cohort (0% for both). Patients in the high-dose cohort also demonstrated a robust improvement in visual function, including mean retinal sensitivity. AGTC-501 was well-tolerated. There were no clinically significant safety events associated with treatment, and treatment-related adverse events were considered mild to moderate in severity.1
“These data, which demonstrate a favorable safety profile and notable improvement in visual function, are another positive step in the development of AGTC-501 for XLRP, a blinding, orphan disease for which there is currently no approved treatment,” Nadia Waheed, MD, chief medical officer of Beacon Therapeutics, said in the news release. “We look forward to announcing the initiation of our Phase 2/3 VISTA trial in the first half of 2024.”
Beacon Therapeutics noted that XLRP is an orphan disease, predominantly caused by mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene. AGTC-501 expresses the full-length RPGR protein, and is expected to rescue function of both rod and cone photoreceptors, making it uniquely well-suited as a potential treatment to improve the lives of patients with XLRP.