An animal study demonstrates the safety and efficacy of a gene therapy treatment in both eyes affected by Leber congenital amaurosis (LCA), a group of disorders involving severe inherited retinal degeneration that leads to blindness by adulthood (Amado D et al. Sci Transl Med. 2010;2ra16).
Previously, scientists had shown that injecting an adeno-associated virus carrying the gene missing in LCA into one eye each in 12 patients with the disorder partially restored vision in the treated eye (Maguire AM et al. Lancet. 2009;374:1597-1605). But the safety of treating the second eye was questioned, given the potential for a complicating immune response after the first injection.
Hampton T. Gene Therapy for Blindness. JAMA. 2010;303(13):1245. doi:10.1001/jama.2010.350