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Published on: January 25, 2019
Intravitreal Aflibercept for Retinal Nonperfusion in Proliferative Diabetic Retinopathy: Outcomes from the Randomized
Charles C Wykoff1, Muneeswar G Nittala2, Brenda Zhou3
1Retina Consultants of Houston, Houston, Texas; Blanton Eye Institute, Houston Methodist Hospital & Weill Cornell Medical College, Houston, Texas.
Purpose:
Evaluate the impact of intravitreal aflibercept (Eylea; Regeneron, Tarrytown, NY) on retinal nonperfusion (RNP) in eyes with proliferative diabetic retinopathy (PDR).
Design:
Prospective, randomized clinical trial.
Participants:
Eyes with treatment-naïve PDR and extensive RNP without diabetic macular edema.
Methods:
Patients were randomized 1:1 to intravitreal 2 mg aflibercept every 4 weeks (monthly) or every 12 weeks (quarterly).
Main Outcome Measures:
The primary outcome measure was change in total RNP area (in square millimeters) from baseline to year 1. Secondary outcomes included ischemic index (ISI), diabetic retinopathy severity scale (DRSS) scores, visual acuity, central retinal thickness, and adverse events. The mean and 95% confidence interval were calculated for each outcome.
Results:
Through 1 year, the monthly (n = 20) and quarterly (n = 20) cohorts received 11.0 and 3.95 mean aflibercept injections, and DRSS scores improved 2 steps or more in 74% and 67% of patients, respectively. Among all patients through 1 year, mean total area of RNP increased from 235 mm2 to 266 mm2 (P = 0.18) and ISI increased from 25.8% to 31.9% (P = 0.004). Retinal nonperfusion outcomes favored monthly dosing. Mean total RNP increased from 207 mm2 at baseline to 268 mm2 (P = 0.01) at 1 year in the quarterly cohort and remained stable at 264 mm2 at baseline and 1 year (P = 0.70) in the monthly cohort (P = 0.05, monthly vs. quarterly cohorts). Although many eyes demonstrated increased areas of RNP longitudinally (n = 24 [66.7%]), this was more common with quarterly dosing (n = 14 [77.8%]), and a proportion of eyes (n = 12 [33.3%]) demonstrated localized areas of apparent reperfusion of nonperfused retina, more commonly in the monthly cohort (n = 8 [44.4%]).
Conclusions:
Widespread evidence of retinal reperfusion with aflibercept dosing of PDR eyes with extensive RNP was not identified, and therefore the primary outcome of the current study was not met. Nevertheless, zones of apparent reperfusion were detected in some patients, and a dose response was identified with a reduction of RNP progression with monthly compared to quarterly dosing.
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