Study participants were at least 18 years of age, had type 1 or 2 diabetes, had at least one eye with a best corrected visual-acuity letter score (range, 0 to 100, with higher scores indicating better visual acuity) of 78 (approximate Snellen equivalent, 20/32) to 24 (approximate Snellen equivalent, 20/320) and center-involved diabetic macular edema on clinical examination and optical coherence tomography (OCT) according to protocol-defined thresholds, and had received no anti-VEGF treatment within the previous 12 months. Other eligibility criteria are listed in Table S1 in the Supplementary Appendix, available at NEJM.org.