Can Gene Therapy Become The Cure For Blindness?

Patients who had lost their sight to an inherited retinal disease could see well sufficient to explore a maze after being treated with a new gene therapy according to the researchers.

Patients in the study had a condition called Leber innate amaurosis (LCA), which starts in infancy and advances gradually, in the long run causing the total blindness. This new, first-of-its-kind Gene Therapy is right now beneath survey by the U.S. Food and Drug Administration for potential approval.

There is currently no cure available for inherited retinal diseases. Information from the primary randomized, controlled, phase 3 study appeared that 27 of 29 treated patients (93 percent) experienced significant advancements in their vision, enough that they may explore a maze in low to moderate light. They also showed advancement in light sensitivity and peripheral vision, which are two visual deficits these patients experience. Approval could open the door for other gene therapies that might eventually treat the more than 225 hereditary mutations known to cause blindness.

It can be applied to retinitis pigmentosa, another inherited retinal disease caused by a defective gene. Or in the future, gene therapy may possibly give key proteins required to reestablish vision in more common diseases such as age-related macular degeneration.LCA is rare, affecting around 1 in 80,000 people. It can be caused by one or more than 19 different genes. The treatment, called voretigene neparvovec (Luxturna, Spark Therapeutics), includes a genetically adjusted version of a harmless virus. The virus is modified to carry a healthy version of the gene into the retina. Researchers infuse billions of modified viruses into both of a patient's eyes. Treatment doesn't restore typical vision. It does, however, permit patients to see shapes and light, permitting them to get around without a cane or a guide dog.

Till now, there is no evidence about how long the treatment will last, but so far, most patients have maintained their vision for two years. More than 200 patients with LCA have taken an interest in gene therapy trials since 2007. However, no gene therapy has gotten this near to FDA approval for retinal disease or any other eye disease. After all the researches, FDA approved the first ever Gene Therapy which targets Rare form of Genetic Blindness.