Beacon Therapeutics reports encouraging interim results from phase 2 clinical trial for XLRP gene therapy

X-linked retinitis pigmentosa (XLRP) is a form of retinitis pigmentosa that affects approximately 20,000 people in the US and EU. Because the mutated gene that gives rise to the condition is on the X chromosome, and males only have one copy of the X chromosome (and thus cannot have a second healthy gene to compensate for the defect), XLRP usually affects males. Though females are usually unaffected carriers of XLRP, they sometimes have vision loss, as well. The condition causes constriction of vision, reduced vision in dark settings, and central vision loss, especially in later stages. Most males with XLRP are legally blind by the age of 45. Beacon Therapeutics has reported vision improvements for five of eight patients receiving the high dose of its XLRP gene therapy in the Phase 2 SKYLINE clinical trial.  Known as AGTC-501, the emerging gene therapy is for patients with mutations in RPGR, the gene most frequently associated with XLRP. The XLRP gene therapy was delivered by a one-time subretinal (under the retina) injection. AGTC-501 uses a human-engineered adeno-associated virus (AAV), which works like a vast container system, to deliver healthy copies of the RPGR gene to cells in the retina. AGTC-501 was well-tolerated and no clinically significant safety events were associated with treatment.

Beacon plans to launch its Phase 2/3 VISTA clinical trial for AGTC-501 during the first half of 2024. For more information on this upcoming trial, visit or

Source: Foundation Fighting Blindness, Eye on the Cure Research News, February 9, 2024; see source article