Scientists have utilised CRISPR gene editing techniques in a clinical trial to treat Leber congenital amaurosis (LCA), a genetic mutation which causes severe visual impairment.
LCA is the most common cause of inherited childhood blindness, and this trial hopes to use advanced gene editing techniques as a one-time permanent treatment to restore sight.
The level of blindness that LCA causes varies, but the majority of people that suffer from it are legally blind with severe sight loss.
Representing the first human in vivo use of CRISPR gene editing, scientists at Allergan and Editas Medicine programmed a harmless virus to enter the body to find and cut out a problematic mutation in the CEP290 gene. Before this, CRISPR had only been used on cells extracted from the body and then reintroduced.
Doctors at Oregon Health and Science University injected a few drops of the treatment behind the patient's retina. In a few weeks the patient will walk through obstacle courses to determine whether the treatment was successful.
Only one patient has been treated so far and the early-stages study is designed primarily to investigate whether injecting the gene-editing tool directly into the eye is safe.
"If we can do this safely, that opens the possibility to treat many other diseases where it's not possible to remove the cells from the body and do the treatment outside," said Dr. Eric Pierce, professor of ophthalmology at Harvard Medical School and director of the Inherited Retinal Eye Disorders Service at Massachusetts Eye and Ear.