Back in January 2014, Digital Journal reported that, following a gene therapy trial, patients who were progressing toward blindness had considerably better vision after completing the treatment. The results of the trial were published in The Lancet. Now comes the news that the effects are not as long-lasting as previously hoped.
The idea that gene therapy can restore sight was first tested out on people with a condition called Leber’s congenital amaurosis. Leber’s congenital amaurosis (LCA) is a rare inherited eye disease that appears at birth or in the first few months of life. The condition is linked to a mutation in the retinal pigment epithelium.
With the therapy, The Scientist summarizes, medics injected “a viral vector carrying an unmutated copy of RPE65 into one eye of each patient, many of whom experienced a heightened sensitivity to light within just a few days.”
However, as the report goes onto describe, the partial restoration of vision has fallen away. This indicates that the gene therapy is not a complete and permanent solution for the condition.
According to a research note: “This study shows that the current therapy doesn’t appear to be the permanent treatment we were hoping for, but the gain in knowledge about the time course of efficacy is an opportunity to improve the therapy so that the restored vision can be sustained for longer durations.”
Despite the delay, further work will be undertaken to explore if gene therapy can restore lost vision.
The new research outcomes have been published in The New England Journal of Medicine. The paper is titled “Improvement and Decline in Vision with Gene Therapy in Childhood Blindness.”
