A new treatment that arrives in a form of gene therapy can be the hope of people with a blinding form of retinal disease. There are eye conditions that can cause irreversible blindness. In gene therapy, a new gene is added to the cells of the patient to replace the genes that are missing or do not work as they should. The approval of a treatment for certain inherited retinal diseases caused by the mutation in the RPE65 gene has been recommended by the U.S. Food and Drug Administration (FDA).
The mutations in the RPE65 gene are responsible for the early onset blindness from eye conditions such as Leber congenital amaurosis, and some forms of retinitis pigmentosa. The future of vision with gene therapy excites many ophthalmologists. Currently, there is no proven and approved medicine or treatments to be offered to people who have vision-threatening inherited retinal disease. If the first gene therapy gains approval, it may allow new treatments for rare to common eye diseases such as macular degeneration.
The Result of Clinical Trials for Luxturna
Luxturna (voretigene neparvovec) is a prescription gene therapy product that is used to treat patients with inherited retinal diseases. In phase 3 of the study, it showed that 93 percent or 27 of 29 treated patients experienced a meaningful improvement in their vision. Patients described that their vision is enough that they can navigate a maze in low to moderate light.
During the trials, patients who did not receive the therapy were not able to navigate the maze in low to moderate light because they did not undergo meaningful vision changes. After the study, some patients chose to have the treatment and they reported that their light sensitivity had improved. They are also able to move through the maze in low to medium light.
The study showed that patients who were treated kept their vision improvement for two years. Unfortunately, the researchers do not know how long the patients will be able to maintain their vision improvement.
Why Are the Eyes the Perfect Target for Gene Therapy?
For scientists and ophthalmologists, the eye as the target for gene therapy makes good sense because it is a small organ and it is easy to get to. Therefore, it is much easier to implant cells in them than elsewhere in the body. The eye is immune-privileged which means that it is less likely that the cells to be implanted will be rejected as the other parts of the body do.