Abstract
IMPORTANCE: Proactive treatment of nonproliferative diabetic retinopathy (NPDR) reduces the risk of progression to vision-threatening complications. OBJECTIVE: To evaluate vascular endothelial growth factor blockade therapy with intravitreal aflibercept injections in eyes with severe NPDR without diabetic macular edema (DME). DESIGN, SETTING, AND PARTICIPANTS: The Study of the Efficacy and Safety of Intravitreal Aflibercept for the Improvement of Moderately Severe to Severe Nonproliferative Diabetic Retinopathy (PANORAMA) was a double-masked 100-week randomized clinical trial conducted in multiple centers worldwide. The study included 402 adults with Diabetic Retinopathy Severity Scale (DRSS) level 47 or 53 with no DME and best-corrected visual acuity of 20/40 or better. INTERVENTIONS: Intravitreal injections of aflibercept, 2 mg, every 16 weeks after 3 initial monthly doses and one 8-week interval (aflibercept 2q16 group); intravitreal injections of aflibercept, 2 mg, every 8 weeks after 5 initial monthly doses, with pro re nata (PRN) dosing beginning at week 56 (aflibercept 2q8/PRN group); or sham injections (control group). MAIN OUTCOMES AND MEASURES: Proportions of eyes with a 2-step or greater improvement in DRSS level, vision-threatening complications, and center-involved DME from baseline to weeks 24, 52, and 100. RESULTS: Among 402 participants (1 eye per participant), the mean (SD) age was 55.7 (10.5) years; 225 (56.0%) were male, and 310 (77.1%) were White. A total of 135 were randomized to the aflibercept 2q16 group, 134 to the aflibercept 2q8/PRN group, and 133 to the control group. At 24 weeks, treatment with aflibercept resulted in a 2-step or greater improvement in DRSS level in 157 of 269 eyes (58.4%) in the combined aflibercept groups vs 8 of 133 eyes (6.0%) in the control group (adjusted difference, 52.3%; 95% CI, 45.2%-59.5%; P < .001). At 52 weeks, 88 of 135 eyes (65.2%) in the aflibercept 2q16 group (adjusted difference, 50.1%; 95% CI, 40.1%-60.1%) and 107 of 134 eyes (79.9%) in the aflibercept 2q8/PRN group (adjusted difference, 64.8%; 95% CI, 55.8%-73.9%) compared with 20 of 133 eyes (15.0%) in the control group (P < .001 for both comparisons) showed a 2-step or greater improvement in DRSS level. Fewer eyes treated with aflibercept vs sham injections developed vision-threatening complications and/or center-involved DME through week 100 (22 of 135 eyes [16.3%] in the 2q16 group [adjusted difference, -34.2%; 95% CI, -44.6 to -23.8] and 25 of 134 eyes [18.7%] in the 2q8/PRN group [adjusted difference, -31.7%; 95% CI, -42.5 to -20.9] compared with 67 of 133 eyes [50.4%] in the control group; P < .001 for both comparisons). No new safety signals were identified. CONCLUSIONS AND RELEVANCE: In this study, significantly more eyes with moderately severe to severe NPDR that were treated with aflibercept showed a 2-step or greater improvement in DRSS level at 24, 52, and 100 weeks, and significantly fewer eyes treated with aflibercept vs sham developed vision-threatening complications and center-involved DME. Outcomes on the DRSS between year 1 and 2 emphasize the need for ongoing vascular endothelial growth factor suppression and adherence. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02718326.