Comparison of Innovator vs. Biosimilar Ranibizumab in Treating Diabetic Macular Edema: A Multicenter Retrospective Study

INTRODUCTION: To compare the efficacy of innovator ranibizumab (iRBZ—Accentrix, Novartis, India) vs. biosimilar ranibizumab (bRBZ, Razumab-Intas, India) in eyes with diabetic macular edema (DME) in an Indian population. METHODS: Data of patients with DME who underwent at least three injections of iRBZ or bRBZ and had a minimum of 6 months follow-up were obtained from an electronic database. Choice of injection depended upon the patient. Pro re nata (PRN) protocol from baseline was used with reinjections advised if the central macular thickness (CMT) was at least 300 μm and best corrected visual acuity (BCVA) was 20/40 or worse. Primary outcome measure was comparison of change in BCVA at 6 months between iRBZ and bRBZ. RESULTS: We included 264 eyes in the iRBZ group and 69 eyes in bRBZ group, which were comparable for baseline characteristics. Mean BCVA improved from 0.64 ± 0.39 logMAR to 0.47 ± 0.31 logMAR (p < 0.001) in the iRBZ group and from 0.71 ± 0.42 logMAR to 0.50 ± 0.29 logMAR in the bRBZ group (p < 0.001) at 6 months. There were no differences in BCVA between the two groups (p > 0.05 for all time points). The CMT reduction in the iRBZ group (120 ± 196 µm) was comparable to that in the bRBZ group at 6 months (105 ± 187 µm) (p = 0.69). There was no difference in the mean number of injections taken (3.81 ± 1.2 in iRBZ vs. 3.55 ± 1.2 in bRBZ) (p > 0.05) between groups. Vision at baseline was the only factor associated with vision at last follow-up after adjusting for CMT at baseline, type of injection, and number of injections. CONCLUSIONS: Biosimilar RBZ is similar to innovator RBZ in improving vision and reducing CMT in eyes with DME in the short term.