Objective
To evaluate effects of intravitreal ranibizumab on diabetic retinopathy (DR) severity over time in 2 phase 3 clinical trials (RIDE, NCT00473382; RISE, NCT00473330) of ranibizumab for diabetic macular edema.
Methods
Participants with diabetic macular edema (n = 759) were randomized to monthly sham, 0.3-mg ranibizumab, or 0.5-mg ranibizumab intravitreal injections. Macular laser was available per protocol-specified criteria. Fundus photographs, taken at baseline and periodically, were graded by a central reading center; clinical examinations were performed monthly. The main outcome measures of this report are secondary/exploratory analyses including a 2-step or more and 3-step or more change on the Early Treatment Diabetic Retinopathy Study severity scale in the study eye and a composite DR progression outcome including photographic changes plus clinically important events such as occurrence of vitreous hemorrhage or need for panretinal laser.
Results
At 2 years, the percentage of participants with DR progression (worsening by ≥2 or ≥3 steps) was significantly reduced in ranibizumab-treated eyes compared with sham-treated eyes, and DR regression (improving by ≥2 or ≥3 steps) was significantly more likely. The cumulative probability of clinical progression of DR as measured by the composite outcome at 2 years was 33.8% of sham-treated eyes compared with 11.2% to 11.5% of ranibizumab-treated eyes.
Conclusions
Intravitreal ranibizumab reduced the risk of DR progression in eyes with diabetic macular edema, and many ranibizumab-treated eyes experienced improvement in DR severity. Because these results are exploratory, the use of intravitreal ranibizumab specifically to reduce DR progression or cause DR regression requires further study.