Abstract
Purpose: :
To compare the treatment of clinically significant diabetic macular edema (CSDME) with 0.5 mg of ranibizumab versus 1.0 mg ranibizumab at different dosing intervals.
Methods: :
Investigator sponsored, prospective, randomized clinical trial. Eyes with clinically significant macular secondary to diabetic retinopathy were randomized to one of two groups, 0.5 mg ranibizumab (0.5 mg/0.05 ml), or 1.0 mg ranibizumab (1 mg/0.1 ml). During the first year, each patient received three monthly injections followed by injections on an every other month as needed re-treatment protocol. During the second year, patients were seen every month and received as needed monthly injections of drug. Some patients were eligible to crossover to a 2 mg dose after the first year.
Results: :
A 24-month analysis included 42 eyes of 42 patients (20 eyes in 0.5 mg group, and 22 eyes in 1.0 mg group). The two groups did not differ at baseline in age, sex, ETDRS letters, OCT central thickness/ volume, or blood pressure. The 1.0 mg group had a baseline ETDRS vision of 60.8 letters with a final vision of 71.2 letters at two years (p=0.0001). The 0.5 mg group had a baseline ETDRS vision of 57.5 letters with a final vision of 64.5 letters at two years (p=0.0001). There was a significant difference between the two dose groups across time for ETDRS vision (p=0.035). The 1.0 mg group had an average gain of 10.4 ETDRS letters as compared with 7.0 letters in the 0.5 mg group (p=0.31). Mean decrease in central foveal thickness was 192µm in the 1.0 mg group and 216µm in the 0.5 mg group (p=0.87). There was a statistically significant difference between the groups with respect to final macular volume at 2 years, with the 0.5 mg group having a higher volume that the 1.0 mg group (7.95 vs. 6.85, p=0.027). In the 1.0 mg group, 27% of patients gained 15 or more ETDRS letters, compared to 15% of patients in the 0.5 mg group (p=0.46). The average number of injections in the 1.0 mg group was 12.0, as compared to 12.9 in the 0.5 mg group (p=0.54). There was no change in blood pressure in either group.
Conclusions: :
Treatment of CSDME with either 0.5 mg or 1.0 mg of ranibizumab resulted in a statistically significant improvement in visual acuity from baseline. There was a significant difference between the two dose groups across time for ETDRS visual acuity. The 1.0 mg dose group had improved resolution of macular edema versus the 0.5 mg ranibizumab group at 2 years. The number of injections did not differ significantly between the two groups.
Clinical Trial: :
http://www.clinicaltrials.gov NCT00440609
Keywords: diabetic retinopathy • macula/fovea • edema