The Food and Drug Adminstration ("FDA") announced, on December 19, 2017, its approval of a gene therapy method developed to improve, or even restore, healthy RPE65 enzyme function by introducing wild-type copies of RPE65 genes directly into RPE tissue. The method involves surgical delivery of RPE65 genes incorporated into adeno-associated viruses. Spark Therapeutics, the company marketing this gene therapy, calls its "drug" voretigene neparvovec-rzyl (brand-named LUXTURNA).
As the FDA announced, LUXTURNA "is the first directly administered gene therapy approved in the U.S. that targets a disease caused by mutations in a specific gene." In the FDA press release, FDA Commissioner, Scott Gottlieb, waxed enthusiastic, suggesting that
this milestone reinforces the potential of this breakthrough approach in treating a wide-range of challenging diseases. The culmination of decades of research has resulted in three gene therapy approvals this year for patients with serious and rare diseases. I believe gene therapy will become a mainstay in treating, and maybe curing, many of our most devastating and intractable illnesses[.]After previous fatal missteps (e.g., see here), gene therapy is finally seeing the light of day.