Could gene therapy treat the inherited eye disorder LCA in the future?
A new study discovered a temporary remedy for patients suffering from Leber congenital amaurosis (LCA), which is a congenital disorder that causes vision loss starting in childhood.
“We now need a more potent gene therapy vector,“ said Prof Robin Ali, the UCL’s Institute of Opthalmology.
Leber congenital amaurosis (LCA) primarily affects the retina, which is the specialized tissue at the back of the eye that determines light and color.
People with this disorder typically have severe visual impairment beginning in infancy.
Almost 10% of the population with this disorder have a mutated form of the gene RPE65, which is responsible for the production of a protein that nourishes light sensors in the retina.
Studies were carried out involving 12 children of ages above six by researchers at University College London’s Institute of Opthalmology and Moorfields Eye Hospital to reveal the results when they are injected with healthy genes into their retinas.
Half of them said their night vision had improved while they claim it continued to improve after 6 to 12 months after the therapy. But, their daytime vision seemed not to show any improvement.
“Gene therapy improves night vision but there is no evidence that it slows progression of the disorder, “ said Prof Robin Ali, head of genetics at UCL’s Institute of Ophthalmology.
The professor said the team had made a new more effective way of bringing the gene to specific cells. The team plan to test the new vector in a clinical trial financed by the Medical Research Council.
Scientists from the University of Pennysylvania did a smaller trial that discovered patients experienced the same improvements which remained for a year to three since therapy.
Dr Samuel Jacobson of the University of Pennsylvania’s Scheie Eye Institute, in Philadelphia, counts that the trial results as vital, even when the therapy does not promise any permanent cure.
“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 in patients.”
The results of the study were published in the New England Journal Medicine.