FLICKR, COMMUNITY EYE WELLNESS Wet age-related macular degeneration (AMD) happens when blood vessels grow and leak fluid into the macula, the central portion of the retina. If left without treatment, this condition can lead to vision loss. A new gene therapy that will blocks vascular endothelial growth factor (VEGF), a proteins that plays a central role in the development of the condition, may be a safe treatment, according to a study published yesterday (May 16) in the Lancet .
Researchers at Johns Hopkins and their collaborators carried out an open-label Phase I clinical trial of a brand new treatment, in which a viral vector expressing the gene pertaining to sFLT01, a protein that neutralizes VEGF, is shot into patients’ eyes. The team enrolled 19 sufferers over age 50 with advanced wet AMD plus divided subjects into five groups that received various doses of the gene.
“ Even on the highest dose, the treatment was quite safe. We discovered there were almost no adverse reactions in our patients, ” study coauthor Peter Campochiaro, a professor of ophthalmology at Johns Hopkins University, said in a statement. The injections decreased fluid levels and improved vision in six individuals.
In five patients where the treatment failed to reduce fluid levels, researchers discovered pre-existing antibodies towards the virus used to deliver the therapy, adeno-associated virus (AAV2). “ Looking towards the future, the possibility of pre-existing neutralising antibodies to AAV2 being an obstacle to the success of the therapy could be partly overcome by prescreening the patients or by the choice of alternative AAV serotypes, ” Elizabeth Rakoczy of the College of Western Australia who was not involved in the study, published in an accompanying comment in the Lancet .
Another newly developed approach to treating ADVANCED MICRO DEVICES has been to implant retinal epithelium derived from induced pluripotent stem cells. The first patient to have received such a therapy, made from donor stem cells, did not have worsening eyesight one year later.