This study focuses on people with Retinitis Pigmentosa, a genetic eye disease that causes progressive vision loss. The condition being studied specifically affects people who have mutations in a part of the USH2A gene called exon 13. The study will test a medication called ultevursen (also known as QR-421a), which is given as an injection into the eye. The purpose is to evaluate how well this treatment works and how safe it is over a period of 24 months.

During the study, participants will receive either ultevursen injections or undergo a sham procedure (which mimics the injection but without actually inserting anything into the eye). The medication will be given as a solution that is injected directly into the eye through a procedure called intravitreal injection. Some participants will receive higher doses of the medication while others will receive lower doses.

The study will track changes in participants’ vision and eye structure using various tests that measure the health of the retina (the light-sensitive layer at the back of the eye). Researchers will particularly focus on measuring a specific layer of the retina called the ellipsoid zone, which is typically affected in people with this condition. They will also monitor participants’ vision in different lighting conditions and their ability to see details and colors.