Researchers recently completed the Phase 1 clinical trial that was conducted to determine the long-term safety of gene transfer to treat neovascular age-related macular degeneration. Results were published in the Human Gene Therapy journal. There were 21 participants who had advanced neovascular age-related macular degeneration in the clinical trial. They received treatment in one eye that included a sub-retinal injection of a viral vector engineered to deliver two therapeutic genes called endostatin and angiostatin. Both of these genes block the formation of blood vessels. It is these formation of blood vessels that are responsible for neovascular age-related macular degeneration. Researchers found that the sub-retinal injections were safe and well-tolerated by the participants. Researchers hope that gene therapy will be successful and will lead to treatments for genetic retinal disorders and also lead to treatments for other more common eye diseases. Additional clinical trials will be needed.