A gene therapy for Leber hereditary optic neuropathy improved patients' vision not only in the eye treated, but also in the untreated eye, New Scientist reports, noting that the finding could have implications for the design of future eye studies.
In a small study published in Science Translational Medicine, an international team of researchers treated 37 patients with visual loss due to Leber hereditary optic neuropathy. The patients all harbored the disease-linked m.11778G>A (MT-ND4) mutation and the therapy delivered cDNA encoding the wild-type protein. While the treatment was only given to one of the patients' eyes — the other eye received a sham treatment as a control — the researchers found that in most patients both eyes unexpectedly experienced improved vision.
Through a primate model, the researchers found that a tagged treatment given to one eye could later be detected in the other as well as in the optic nerves, suggesting it moved along one eye's optic nerve to the other eye's optic nerve.
"I'm not sure this is good or bad news, but it's fascinating news," University College London's Michel Michaelides tells New Scientist. "It's an important finding that should be taken into account when designing studies."