Baseline Diabetic Retinopathy Severity and Time to Diabetic Macular Edema Resolution with Ranibizumab Treatment

Objective: Having a better understanding of how long diabetic macular edema (DME) takes to resolve in patients with diabetic retinopathy (DR) after treatment with ranibizumab, and the factors affecting this outcome, would be of benefit to physicians and patients alike. The objective of this analysis was to evaluate the time to first DME resolution and the impact of baseline DR severity on this outcome in patients treated with ranibizumab in phase III clinical trials.Design: Meta-analysis of data from the phase III trials, RIDE (NCT00473382) and RISE (NCT00473330), and DR Clinical Research Network protocols I (NCT00444600), S (NCT01489189), and T (NCT01627249).Participants: Patients with DME (central subfield thickness [CST] > 250 mm) and DR with Diabetic Reti-nopathy Severity Scale (DRSS) score between 35 and 85.Intervention: Intravitreal injection of ranibizumab.Main Outcome Measures: The time to first DME resolution (defined as CST < 250 mm) within 24 months was evaluated overall and by baseline DR severity category per the DRSS (35 of 43 [mild or moderate non-proliferative DR], 47-53 [moderately severe or severe nonproliferative DR], 60 [mild proliferative DR], and 61-85 [moderately severe to severe proliferative DR]).Results: There were 777 patients included in the meta-analysis. The overall mean (95% confidence interval) time to first DME resolution, adjusted for baseline CST, was 6.0 (5.6-6.4) months. The mean (95% CI) time to first DME resolution was 7.1 (6.2-7.9), 5.9 (5.2-6.6), 6.0 (4.8-7.2), and 4.5 (3.5-5.5) months for the 35 of 43, 47 to 53, 60, and 61 to 85 baseline DRSS categories, respectively (overall P = 0.002). By month 24, the proportion of eyes with DME resolution was 74.9% (221 of 295), 77.5% (299 of 386), 69.4% (109 of 157), and 78.7% (148 of 188) for the 35 of 43, 47 to 53, 60, and 61 to 85 baseline DRSS categories, respectively (overall P = 0.17).Conclusions: This meta-analysis of data from patients treated with ranibizumab showed that DME resolution was faster in patients with more severe DR at baseline. However, by month 24, a similar proportion of patients achieved DME resolution, regardless of baseline DR severity. These findings may guide treatment decisions and inform patient expectations in clinical practice.