Gene Therapy to Reverse Effects of Blindness: Science Fiction or Reality?

By: Rachel Theodorou

The FDA is considering a new type of gene therapy that may be able to reverse the effects of gene mutation that causes blindness. This therapy, Luxturna (voretigene neparvovec is its scientific name), targets the RPE65 gene, which causes Leber’s congenital amaurosis (LCA), a rare form of blindness that begins during infancy. If Luxturna is approved for widespread use, it will become the first gene therapy for the treatment of an inherited disease in United States history.

The procedure involves injecting a non-mutated RPE65 gene directly into the eye. In order to get the healthy gene into the retinal cell, researchers at the Children’s Hospital of Philadelphia and the University of Pennsylvania engineered a virus that would carry the healthy gene to the cells. The thought of injecting a virus into an eye is a frightening concept for many, but the potential downsides and side effects of Luxturna are few and far between. Similar to receiving a vaccine, injecting a virus into your body has the potential to cause harm in the form of spreading to other cells or causing an allergic reaction (also known as an immune reaction). Luxturna is not injected into the bloodstream, however, so its odds of spreading are incredibly low due to the eye’s isolated, self-contained nature.

Luxturna is the only gene therapy of its kind to render long-lasting results; other similar gene therapies have only temporarily restored eyesight. Twenty-seven out of twenty-nine patients who received the treatment as part of an experimental clinical trial showed a substantial improvement in functional vision, as demonstrated by a mobility assessment. While the FDA has yet to make a final decision, it is likely that Luxturna will be approved because of its high success rate and minimal side effects.

Cites:

Susan Scutti, Experimental gene therapy for blindness considered by FDA, CNN (last visited Oct. 12, 2017), http://www.cnn.com/2017/10/11/health/gene-therapy-blindness-fda/index.html.