Three Patients Have Second Eyes Treated in LCA Gene Therapy Trial at CHOP
The news coming from the landmark gene therapy clinical trial for Leber congenital amaurosis (LCA) at The Children’s Hospital of Philadelphia (CHOP) continues to be very encouraging.
Dr. Jean Bennett, a lead investigator for the Phase I study, reports that three of the 12 trial participants have had their second eyes treated. She says that those three patients are doing well and delighted to have the gene therapy applied to both eyes. Dr. Bennett plans to formally report on the results of treating second eyes in a few months.
Treating the second eye is a critical safety milestone for the study, because it is important for the investigators to demonstrate that treating both eyes does not elicit an immune response.
A total of 12 people, ranging from ages eight to 44, have received treatment in the study. All had one eye treated initially. The participants were virtually blind coming into the trial and have demonstrated sustained improvements in their vision after receiving treatment. As the Foundation reported previously, one nine-year-old boy has put away his white cane and can now see the blackboard at school and ride his bike. The first participant treated in the trial received the therapy more than 3.5 years ago.
CHOP is planning a Phase III clinical trial of the gene therapy for people with LCA for this fall.
More than 30 people have been treated in three LCA gene therapy trials that began in 2007 and 2008. The Foundation is funding the CHOP study as well as the clinical trial taking place at the Moorfields Eye Hospital in the U.K. The other study is being conducted by the University of Pennsylvania and the University of Florida. The Foundation also funded much of the preclinical work that made all these trials possible.
These studies represent the first-ever clinical trials of gene therapy to treat a retinal degenerative disease, and have opened the door for human studies of gene therapy to treat a broad spectrum of retinal conditions.
The treatment is for people with LCA caused by variations in the gene RPE65, and involves a one-time injection of a manmade therapeutic virus that delivers a corrective gene to the cells of the retina. |
