ProQR Therapeutics N.V. announced it has completed patient enrollment in its Phase 2/3 Illuminate study of sepofarsen for the treatment of Leber Congenital Amaurosis 10 (LCA10) due to the p.Cys998X mutation in the CEP290 gene. With enrollment completed, top-line results are expected in the first half (H1) of 2022. Illuminate is a Phase 2/3 trial, which randomized 36 patients aged eight years or older to receive either sepofarsen at the target registration dose, a low dose, or sham treatment. The primary endpoint of this study is mean change from baseline in Best Corrected Visual Acuity (BCVA) at Month 12, at the registration dose versus sham. This trial is intended to support application for marketing approval of sepofarsen for patients with LCA10 due to the p.Cys998X mutation in the CEP290 gene. The Illuminate study was initiated based on data from a Phase 1/2 study, which indicated that at Month 12, patients treated with sepofarsen had an improvement in visual acuity, as measured by BCVA. In a subset of patients (n=6) who were treated at the target registration dose, the mean change from baseline for BCVA at Month 12 was -0.93 LogMAR, equivalent to approximately 9 lines improvement (or 45 letters) on the ETDRS chart. In the Phase 1/2 study, concordant improvements in measures of full-field stimulus testing (FST) and mobility were also observed, which are secondary endpoints in the Illuminate trial. Sepofarsen has been granted orphan drug designation in the United States and the European Union and received fast-track designation and rare pediatric disease designation from the FDA as well as access to the PRIME scheme by the EMA.