Optogenetic gene therapy found safe and partly restores sight in 10 blind people

Mixed · 2A paper published on Wednesday 7 October 2026 in the New England Journal of Medicine reports that optogenetic therapy, a type of gene therapy, is safe and can partly restore sight in blind people. 1 2 Left · 1The trial involved 10 people with advanced retinitis pigmentosa, including the patient in whom the approach was first shown to partly restore vision in 2021 and nine others. 1 Centre · 1Retinitis pigmentosa is a genetic disorder in which light-sensing cells of the retina degenerate. It is usually diagnosed in childhood or adolescence and often leads to legal blindness by young adulthood. Apart from a subset of patients with a specific mutation who can have gene therapy, there is no cure. 2

Left · 1The Guardian says the group of disorders is thought to affect more than 1.5 million people worldwide. 1 Left · 1The therapy is a single eye injection of a harmless, synthetic virus that carries instructions for a light-sensitive protein into a ring of surviving retinal ganglion cells, which are less affected by the disease. Because it does not depend on the genetic cause of sight loss, it could apply to many patients. 1 Left · 1Each patient then wears goggles that capture images and convert them into pulses of light of a single wavelength, which activate the modified cells so the wearer perceives a monochrome image. 1

Left · 1Only the eye with the worse vision was treated, and outcomes were followed for up to five years. One severe eye-related side effect occurred and resolved within minutes, and there were no therapy-related side effects elsewhere in the body. 1 Mixed · 2Six of the 10 participants had clinically meaningful improvements in light sensitivity; STAT summarises this as about half of patients regaining photosensitivity. 1 2 Left · 1Some participants also improved at tasks while wearing the goggles, such as detecting, locating and touching a notebook, locating a door and walking on a line, and those who trained more with the goggles tended to do better. 1

Left · 1The study has limits: patients can detect objects but not yet faces, which lead author Prof Botond Roska of the Institute of Molecular and Clinical Ophthalmology Basel attributes to the treated cells sitting in a ring around the fovea. Roska said the concept is valid for vision restoration and hopes to achieve high-resolution vision in five to 10 years. 1 Left · 1Mark Hankins, professor of visual neuroscience at the University of Oxford, who was not involved, said the study offers reassurance on safety and shows stable restoration of some light sensitivity lasting four to five years, calling the results "baby steps, but they’re critical". 1 Mixed · 2The approach draws on optogenetics, the technique of controlling nerve cells with light, which both outlets link to the recently announced 2026 Nobel prize in physiology or medicine. 1 2