Source insciences.org Image: Albert M. Maguire, M.D; Katherine High, M.D.; and Jean Bennett, M.D., Ph.D., are co-authors of the study published in The Lancet. The gene therapy vector (shown) used in the study was manufactured at the Center for Cellular and Molecular Therapeutics at The Children’s Hospital of Philadelphia. (Image from insciences.org)

PHILADELPHIA – Born with a retinal disease that made him legally blind, and would eventually leave him totally sightless, the nine-year-old boy used to sit in the back of the classroom, relying on the large print on an electronic screen and assisted by teacher aides. Now, after a single injection of genes that produce light-sensitive pigments in the back of his eye, he sits in front with classmates and participates in class without extra help. In the playground, he joins his classmates in playing his first game of softball.

His treatment represents the next step toward medical science’s goal of using gene therapy to cure disease. Extending a preliminary study published last year on three young adults, the full study reports successful, sustained results that showed notable improvement in children with congenital blindness.

The study, conducted by researchers from the University of Pennsylvania School of Medicine and the Center for Cellular and Molecular Therapeutics at The Children’s Hospital of Philadelphia, used gene therapy to safely improve vision in five children and seven adults with Leber’s congenital amaurosis (LCA). The greatest improvements occurred in the children, all of whom are now able to navigate a low-light obstacle course—one result that the researchers call “spectacular.”

“This result is an exciting one for the entire field of gene therapy,” said Katherine A. High, M.D., co-first author of the study and the director of the Center for Cellular and Molecular Therapeutics, the facility that sponsored the clinical trial at The Children’s Hospital of Philadelphia. High, an investigator of the Howard Hughes Medical Institute and a past president of the American Society of Gene Therapy, has been a pioneer in translational and clinical studies of gene therapy for genetic disease. “This study reports dramatic results in restoring vision to patients who previously had no options for treatment,” said High. “These findings may expedite development of gene therapy for more common retinal diseases, such as age-related macular degeneration.”