Gene therapy: Blind people managed to identify objects with special glasses

A first-of-its-kind clinical trial in a group of patients with retinitis pigmentosa, a genetic disease that leads to blindness, shows that optogenetic therapy is safe and allows the brain to learn to decipher new light signals. Ten participants received an eye injection and special glasses; seven showed improvement in light sensitivity, and six were able to identify objects and reach out accurately. Vision did not return to normal.

A first-of-its-kind clinical trial, published in the New England Journal of Medicine (NEJM), shows that gene therapy combined with special glasses enables blind people to identify objects and reach out accurately. Ten patients with a genetic disease called retinitis pigmentosa, which causes gradual death of photoreceptor cells in the retina, received an injection in one eye. The treatment, called optogenetics, teaches other retinal cells to produce a light-sensitive protein. Glasses with a small camera translate the image into pulses of orange light projected onto the retina. Seven patients showed improvement in light sensitivity, and for six the improvement was defined as significant: they learned to identify objects, find a door, and reach out accurately. The researchers emphasize that this is not normal vision – participants still cannot read or recognize faces. However, this is the first time it has been demonstrated in a group of patients that the treatment is safe and that the brain learns to process the new signal. The trial was funded by the French company GenSight Biologics, and involved the University of Pittsburgh, the IOB Institute in Basel, the Institut de la Vision in Paris, and Moorfields Eye Hospital in London. At this stage, it is a small trial without a control group, primarily designed to test safety. Larger trials are needed before it becomes an available treatment.