The findings support treating eyes with the condition before they progress to proliferative diabetic retinopathy.
Mitchell Goff, MD
New study findings demonstrate ranibizumab treatment leads to more rapid improvement in eyes with moderately severe or severe nonproliferative diabetic retinopathy compared to those with milder or more severe diabetic retinopathy at baseline.
The research, presented at the American Society of Retina Specialists (ASRS 2020) Virtual Sessions, supported treating eyes with moderately severe or severe nonproliferative diabetic retinopathy before they progress to proliferative diabetic retinopathy.
Mitchell Goff, MD, and colleagues analyzed the RIDE and RISE identical phase 3 trials of monthly ranibizumab (.3 mg and .5 mg) in patients with diabetic retinopathy and vision loss due to diabetic macular edema. Trial patients either received a sham injection (n=257 patients), ranibizumab .3 mg (n=250 patients), or ranibizumab .5 mg (n=252). Severity of diabetic retinopathy was graded from color fundus photographs by masked reading center evaluators using the Early Treatment Diabetic Retinopathy Study (ETDRS) Diabetic Retinopathy Severity Scale (DRSS).
Goff and the team’s primary outcome was the proportion of those who gained at least 15 letters on the ETDRS-DRSS.
Patients in the sham group were crossed over at month 24 to receive ranibizumab for the following 12 months. In those treated with ranibizumab, improvements in diabetic retinopathy severity were seen as early as month 3 and were sustained through month 36.
Overall, 443 eyes were evaluated by the team. The time to at least two-step diabetic retinopathy improvement was significantly shorter among eyes with moderately severe or severe nonproliferative diabetic retinopathy at baseline compared to eyes with either mild or moderate nonproliferative diabetic retinopathy or proliferative diabetic retinopathy at baseline.
The investigators reported few eyes with proliferative diabetic retinopathy and a history of prior panretinal photocoagulation achieved at least two-step diabetic retinopathy improvement. Of those that did achieve improvement, the time to at least two-step improvement was significantly longer than in eyes with no prior panretinal photocoagulation.
Similar to previously reported study outcomes, there was a greater proportion of those achieving at least two-step diabetic retinopathy improvement at month 6 in eyes with moderately severe or severe nonproliferative diabetic retinopathy at baseline than in eyes with either less or more severe baseline diabetic retinopathy. Baseline diabetic retinopathy severity, prior panretinal photocoagulation, and diabetic macular edema at month 3 were predictive at early diabetic retinopathy improvement, Goff said during his presentation of the research. Previous analyses demonstrated those with moderately severe to severe nonproliferative diabetic retinopathy were more likely to achieve clinically meaningful improvements in the severity of their condition with ranibizumab.
“These findings support treating eyes with moderately severe or severe (nonproliferative diabetic retinopathy) before they progress to (proliferative diabetic retinopathy), Goff concluded.
The study, “Baseline Diabetic Retinopathy Severity Affects Time to Clinically Meaningful Improvements in Diabetic Retinopathy During Ranibizumab Treatment,” was presented at ASRS 2020.