Australian researchers have successfully tested a gene therapy for age-related macular degeneration (AMD) which could mean the end of regular intravitreal injections for patients living with the condition.
The initial results of an ongoing trial in 40 patients with wet-AMD were presented at the recent annual meeting for the Association for Research in Vision and Ophthalmology in Orlando, Florida.
The first data from eight of the patients show that the therapy is safe and was well tolerated. Six of the eight who received the treatment (the other two received placebo) showed no loss of visual acuity, retinal detachment or systemic or intraocular inflammation up to a year after treatment.
The approach works by injecting a modified virus underneath the retina, which then delivers its genetic payload – which interferes with the production of a growth factor involved in the condition, VEGF.
Professor Ian Constable, of the Lions Eye Institute in Perth, Australia, and principle investigator, told Medical Xpress: “The gene therapy involves a single injection of a modified and harmless version of a virus containing a specific gene that stimulates supply of a protein which then blocks over-production of VEGF.”
The data also suggest that the gene therapy does not interfere with previous or subsequent injections of the widely used anti-VEGF treatment, ranibizumab. These positive initial results mean the treatment can advance to larger trials.
Professor Constable added: “After the Perth trial, multi-centre studies will have to be run in the United States and FDA (US Food and Drug Administration) approval sought, but we believe we are on track to test the investigational therapy in more patients, and, if proven safe and effective, make it widely available.”