A Statement from Dr. Stephen Rose about Recent LCA Gene-Therapy Findings
The Foundation Fighting Blindness is aware of the most recent results of the University of Pennsylvania and Moorfields RPE65/LCA2 gene-therapy trials, which were recently published in The New England Journal of Medicine and presented before the Association for Research in Vision and Ophthalmology on Sunday, May 3. These dosing trials have shown that retinal gene therapy for LCA2 is safe and that there is substantial improvement of vision in the treated area of the retina. In the most recent data from the University of Pennsylvania trial, which reported on three of the 15 participants, the investigators report that, over 4.5 years following treatment, there is an ongoing retinal degeneration in the treated area, and that correlates with a reduction in the original gain of vision reported.
Despite this change, the visual function of the treated area is still greater than the untreated surrounding region. An important fact to remember is that there are three different gene-therapy drugs being tested for RPE65, as well as differences in the drug composition, administration and population of patients tested. This information is not likely to deter progress in gene therapy. This is another piece of the puzzle that may have relevance as dosing and AAV constructs progress.
The Foundation awaits the longer-term results of the other gene-therapy drugs for this and other inherited rare retinal degenerations. As with all new drug development, there are lessons to be learned from early clinical trials that inform the next generation of treatment, and the Foundation believes that gene-therapy programs will continue to be developed.