Data has shown the success of a new therapy to combat Leber congenital amaurosis (LCA), one of the leading causes of blindness in children, in LCA patients with CEP290 mutations. CEP290 acts as a barrier between two compartments of photoreceptor cells in the eye which convert light into signals, creating vision. Blindnesses caused by CEP290 mutations are the most common form of LCA.

During the study, individuals received an injection of an oligonucleotide, a short RNA molecule, into their eye. This molecule was specifically created to lessen mutant protein levels in the photoreceptors and make the retina function normally.

Three months after their first injection, five of the ten patients in the study showed improvements in visual acuity, and could read letters or distinguish the direction of black and white bars. Further evaluations showed that it was primarily the cone photoreceptors used for daytime vision which were improving after the injections.

Dr Artur Cideciyan PhD, a research professor of ophthalmology at the University of Pennsylvania, said that in the future patients carrying two identical splicing mutations will be evaluated to understand whether the injection’s effectiveness could be even better.