JUN 04, 2021
Investigators evaluated the efficacy of intravitreous aflibercept injections in mitigating complications in eyes with moderate to severe nonproliferative diabetic retinopathy (NPDR).
The DRCR Retina Network Protocol W included adults with type 1 or 2 diabetes and moderate to severe NPDR. Researchers randomized 399 eyes to receive 2 mg of intravitreal aflibercept or sham injections at baseline and at each study visit through 2 years (1, 2, and 4 months, and then every 4 months). The primary outcome was development of center-involved diabetic macular edema (DME) with vision loss or proliferative diabetic retinopathy (PDR).
Compared with the sham group, the aflibercept group had a lower 2-year cumulative probability of developing PDR (14.5% vs. 33.2%) and DME (4.1% vs. 14.8%). The cumulative probability of developing high-risk PDR any time within 2 years was 2.4% with aflibercept and 8.9% with sham. During the study period, the average change in visual acuity was -0.9 letters with aflibercept and -2 letters with sham.
Retention was 80% to 84% during the study period; data missing due to loss to follow-up may have affected the final results. While the 2-year findings are informative, vision-threatening complications may take longer to develop. The 4-year results will be helpful in deciding whether to implement prophylactic anti-VEGF therapy.
Among eyes with moderate to severe NPDR, aflibercept conferred a more than 3-fold reduction in the incidence of center-involved DME and a more than 2-fold reduction in PDR. However, through 2 years, preventive treatment did not provide improved visual acuity compared with observation plus aflibercept if complications developed.