Intraocular injections of VEGF-neutralizing proteins provide tremendous benefits in patients with choroidal neovascularization (NV) due to age-related macular degeneration (AMD), but during treatment some patients develop retinal atrophy. Suggesting that VEGF is a survival factor for retinal neurons, a clinical trial group attributed retinal atrophy to VEGF suppression and cautioned against frequent anti-VEGF injections. This recommendation may contribute to poor outcomes in clinical practice from insufficient treatment. Patients with type 3 choroidal NV have particularly high risk of retinal atrophy, an unexplained observation. Herein we show in mouse models that VEGF signaling does not contribute to photoreceptor survival and functioning: (a) neutralization of VEGFR2 strongly suppresses choroidal NV without compromising photoreceptor function or survival; (b) VEGF does not slow loss of photoreceptor function or death in mice with inherited retinal degeneration, and there is no exacerbation by VEGF suppression; and (c) mice with type 3 choroidal NV develop retinal atrophy due to oxidative damage with no contribution from VEGF suppression. Intraocular injections of VEGF-neutralizing proteins, a highly effective treatment in patients with neovascular AMD, should not be withheld or reduced due to concern that they may contribute to long-term visual loss from retinal atrophy.
Da Long, Yogita Kanan, Jikui Shen, Sean F. Hackett, Yuanyuan Liu, Zibran Hafiz, Mahmood Khan, Lili Lu, Peter A. Campochiaro