Prophylactic Ranibizumab to Prevent Neovascular Age-Related Macular Degeneration in Vulnerable Fellow Eyes

To determine whether prophylactic ranibizumab prevents the development of neovascular age-related macular degeneration (nAMD) in eyes with intermediate age-related macular degeneration (AMD) for patients with preexisting nAMD in their contralateral eye. Multicenter randomized clinical trial. Adults aged 50 years and older with intermediate AMD (multiple intermediate drusen [≥63 μm and <125 μm] or ≥1 large drusen [≥125 μm] and pigmentary changes) in the study eye and nAMD in the contralateral eye. Intravitreal ranibizumab injection (0.5 mg) or sham injection every 3 months for 24 months. Conversion to nAMD over 24 months (primary). Change in best-corrected visual acuity from baseline to 24 months (secondary). Among 108 enrolled participants (54 [50%] in each group), all except 2 were non-Hispanic Whites, 61 participants (56%) were female, and the mean age was 78 years. The mean baseline visual acuity was 77.7 letters (Snellen equivalent 20/32). Conversion to nAMD over 24 months occurred among 7 of 54 eyes (13%) in both groups (ranibizumab vs. sham hazard ratio = 0.91 [95% confidence interval (CI), 0.32–2.59]; P = 0.86). At 24 months, the cumulative incidence of nAMD adjusted for loss to follow-up was 14% (95% CI, 4%–23%) in the ranibizumab group and 15% (95% CI, 4%–25%) in the sham group. At 24 months, the mean change in visual acuity from baseline was −2.1 letters (standard deviation, 5.4 letters) with ranibizumab and −1.4 letters (standard deviation, 7.7 letters) with sham (adjusted difference = −0.8 letters [95% CI, -3.7 to 2.2 letters]; P = 0.62). The proportion of eyes that lost at least 10 letters of visual acuity from baseline at 24 months was 2 of 39 (5%) with ranibizumab and 4 of 40 (10%) with sham. There were no serious ocular adverse events in either group. Quarterly dosing of 0.5 mg ranibizumab in eyes with intermediate AMD did not reduce the incidence of nAMD compared with sham injections; however, the study was likely underpowered given the 95% CI, and a clinically meaningful effect cannot be excluded. There also was no effect on visual acuity at 24 months. Other strategies to reduce neovascular conversion in these vulnerable eyes are needed.