Leber congenital amaurosis: Ocular Genetic Studies

Leber congenital amaurosis (LCA) is a group of hereditary retinal dystrophies that results in severe vision loss and blindness starting early in the first months of life. Voretigene neparvovec-rzyl (VN) is the first gene therapy for biallelic RPE65-associated LCA approved by U.S. Food and Drug Administration and European Medicines Agency. In clinical studies, although it is not always possible to obtain visual acuity improvement in the presence of viable retinal cells, improved retinal sensitivity, improved mobility in dim light conditions and subjective satisfactory results of functionality have been reported. The effect of gene therapy starts within weeks and is maintained for years. VN gene therapy does not cause serious systemic side effects. Ocular side effects may be observed due to subretinal injection procedure and surgery. Apart from VN which is a gene replacement therapy, clinical trials on different gene therapy techniques and gene mutations associated with LCA and are ongoing.