Experimental gene therapy restores limited sight in blind patients
A small, peer-reviewed study reports improvements in light sensitivity and simple visual tasks among some participants with retinitis pigmentosa.
An experimental treatment improved limited visual functions in some of ten blind participants with advanced retinitis pigmentosa. The results were published in the New England Journal of Medicine, but come from a small, open-label study and do not yet constitute a proven treatment.
The therapy combines a one-off gene-therapy injection into one eye with special glasses that emit pulses of light. The gene therapy is intended to make surviving nerve cells in the retina sensitive to light, allowing the glasses to stimulate visual information.
Seven of the ten participants became more sensitive to light after treatment. In six participants, the improvement was large enough, according to the researchers, to be considered clinically meaningful. Four of the eight participants who completed the behavioural tests performed better on tasks requiring them to detect or locate simple objects.
The treatment did not restore normal vision. The researchers report that participants could not read again as someone with normal eyesight could. The improvement also depended on using the special glasses.
The main outcome of this phase 1/2 study was safety. Thirty-four eye-related adverse events were reported in nine participants; they were mainly mild or moderate in severity. One serious event, a temporary blockage of a blood vessel in the retina, disappeared within minutes of treatment.
Because the study was open-label and small, it cannot be ruled out that expectations, practice or other factors influenced some of the outcomes. There was no large control group against which the researchers could definitively compare efficacy.
The publication was peer-reviewed and builds on earlier results in one patient. The new study shows that the concept appears feasible in a small group, but says little yet about long-term safety, its effectiveness in larger groups or its applicability to other forms of blindness.
The researchers and hospitals involved stress that further research is needed. For people with retinitis pigmentosa, this therefore does not represent an immediately available standard treatment or personal medical advice.
The hopeful element is limited but concrete: after treatment and with the glasses, several participants could perceive light or simple objects better than before. The scientific status remains that of early clinical research, not a breakthrough that can already be widely applied.
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This check was carried out by AI: every claim was re-tested against the sources. Even an approved article can contain errors — stay critical.
The study data were checked directly in the peer-reviewed article and with the university involved. The text emphasises the small sample size, the limited outcomes and the need for further research.
- confirmed The study included ten participants with advanced retinitis pigmentosa. — Confirmed in the abstract of the NEJM article. source
- confirmed Seven participants became more sensitive to light and six achieved a clinically meaningful improvement. — Confirmed in the results of the NEJM article. source
- confirmed The treatment did not restore normal vision or reading ability. — Confirmed by the University of Pittsburgh Medical Center. source
- confirmed There were 34 eye-related adverse events, including one serious but temporary event. — Confirmed in the NEJM article. source
- confirmed The study was open-label and early-phase. — The study design is stated in the NEJM article and the institutional commentary. source
Editor's note
The study is peer-reviewed, but small, open-label and early-phase. The results are hopeful for a limited group of participants, but do not prove broad efficacy or an immediately available treatment.Sources
- Optogenetic Therapy for Restoring Aspects of Visual Function — New England Journal of Medicine
- Optogenetic Therapy Shows Signs of Vision Restoration — University of Pittsburgh Medical Center
- Optogenetic therapy is safe and allows blind people to detect objects — EurekAlert! / Institute of Molecular and Clinical Ophthalmology Basel
More on this in Dutch media
- AD — „gentherapie retinitis pigmentosa”
- de Volkskrant — „gentherapie retinitis pigmentosa”
- RTL Nieuws — „gentherapie retinitis pigmentosa”