Efficacy of Conversion to Aflibercept for Diabetic Macular Edema Previously Refractory to Bevacizumab or Ranibizumab: A Meta-analysis of High-Quality Nonrandomized Studies.

Aflibercept has been widely used in treating diabetic macular edema (DME). However, the effect of aflibercept in treating DME refractory to bevacizumab or ranibizumab has not been well established. To assess the therapeutic effect of switching from bevacizumab or ranibizumab to aflibercept in the treatment of refractory DME. Relevant studies were searched from 3 databases: the Cochrane Library, PubMed, and Web of Science. Data on changes in best-corrected visual acuity (BCVA), central macular thickness (CMT), and adverse events within the follow-up period were collected and pooled using weighted mean differences (WMDs) with corresponding 95% CIs in a random effects model. The between-study heterogeneity was tested using the χ test and the 2 statistic, and funnel plots were used to evaluate the publication bias. A total of 11 nonrandomized trials met the inclusion criteria and were included in the meta-analysis. Our studies showed significant improvements in the BCVA (WMD = 100.55; 95% CI = 68.46 to 132.63; < 0.01) and reduction in CMT (WMD = 0.09; 95% CI = 0.03 to 0.14; < 0.01) after switching to aflibercept. Although a large amount of heterogeneity was detected in the CMT results among these studies, the sensitivity analyses showed the reliability and stability of our results. There were significant improvements in both visual and anatomical outcomes after switching from bevacizumab or ranibizumab to aflibercept, without risk of adverse events. Thus, switching therapy may be a safe and effective treatment for patients with refractory DME.