Encouraging Gene Therapy Results in Genetic Form of...( NEW ROCHELLE N.Y. Sept. 8 /- All ...),Health

NEW ROCHELLE, N.Y., Sept. 8 /PRNewswire/ -- All three patients who received intraocular adeno-associated virus-based gene therapy to treat Leber congenital amaurosis (LCA), an incurable genetic disorder that results in blindness, had improved vision, according to a paper published online ahead of print in Human Gene Therapy, a peer-reviewed journal published by Mary Ann Liebert, Inc. These promising results provided evidence of therapeutic efficacy, complementing two other recent LCA clinical trial reports in the New England Journal of Medicine. The Human Gene Therapy paper is available free online at http://www.liebertpub.com/hum

LCA can be caused by many different genes but the newly treated form is caused by mutations in the RPE65 gene, which is essential for maintenance of sight. A group of researchers from the University of Pennsylvania (Philadelphia) and University of Florida (Gainesville) injected copies of a normal RPE65 gene into one eye each of three young adults with LCA. The patients underwent follow-up examinations for 90 days to assess changes in the eye and in their vision compared to the untreated eye. The replacement RPE65 gene was packaged in a gene therapy vector engineered from a recombinant adeno-associated virus.

All of the patients self-reported improved vision under dim light conditions, and the authors measured significant increases in dark-adapted visual sensitivity in the treated eye after therapy compared to before therapy; the untreated eyes did not change.

In a paper entitled, "Phase I Trial of Leber Congenital Amaurosis due to RPE65 Mutations by Ocular Subretinal Injection of Adeno-Associated Virus Gene Vector: Short-Term Results," the authors reported no vector-related serious adverse events, immune reactions, or systemic toxicity.

"Human ocular gene therapy for inherited retinal disease is undergoing a birth experience as early phase trials r
'/>"/>