Gene therapy has helped three adults with an eye disorder dramatically improve their vision, according to a new report published Feb. 8 in Science Transitional Medicine.
The patients have Leber congenital amaurosis type 2 (LCA2), an inherited eye disease that disrupts transmission of light to the retina. According to Medscape Medical News, it usually first appears in childhood and eventually leads to total blindness.
The study continues a previous trial that corrected the genetic fault in one of the eyes of 12 patients. The researchers accomplished this by administering an engineered virus carrying the gene RPE65. In the follow-up study, Dr. Jean Bennett and colleagues treated the other eye of three of those patients.
Bennett told the BBC that the study subjects were now capable of performing a number of new tasks, including walking around at night, shopping for groceries and recognizing faces.
One of the patients, Tami Morehouse, told the BBC how elated she was when she realized she could make out her children’s faces again. “Any amount of vision that you can get when you have almost nothing is incredibly valuable,” she said.
"We've shown that it is possible to safely treat both eyes of people with this particular form of retinal deficiency using a gene-based treatment and further we've demonstrated that the brain understands what the retina is seeing,” Bennett told the BBC.
MRI scans showed the brain responding to visual stimuli after treatment.
Medscape reports that the US Food and Drug Administration has not approved gene therapy, but the study authors believe it is a safe, effective and long-lasting treatment option for LCA2.
