Transitioning from Aflibercept to Biosimilar Ranibizumab in Diabetic Macular Edema (DME): (The TRANSFORM-DME Trial) a Multicenter Observational Study

Purpose: To evaluate visual and anatomical outcomes following a switch from intravitreal Aflibercept (IVI AFL) (T1) to biosimilar Ranibizumab (B-RBZ) (T2) in patients with diabetic macular edema (DME).

Methods: This was a multicenter observational study, analysing medical records of consecutive, treatment-naïve centre-involving DME patients having a baseline visual acuity (VA) of ≥55 Early Treatment Diabetic Retinopathy Study (ETDRS) letters. DME patients, having received monthly loading doses of IVI AFL(T1) and responsive to it, who subsequently shifted to B-RBZ(T2) motivated by financial constraints rather than a lack of efficacy to IVI AFL were identified.

Results: This study included 57 participants (mean age: 54.23 ± 6.91 years), with 80.7% male patients. VA improved during T1, from 61.4 ± 11.74 ETDRS letters at baseline to 72.7 ± 8.05 ETDRS letters (mean change: +11.2 letters, 95% CI: 9.1 to 13.4; p < 0.001). During T2, VA declined slightly over 12 months with a mean VA of 69.9 ± 3.78 ETDRS letters at the 12-month mark (+8.5 letters from baseline; p < 0.001). Mean central macular thickness (CMT) during T1 reduced from 411.9 ± 34.62 μm at baseline to 279.3 ± 9.96 μm (mean change: -132.6 μm, 95% CI: -142.2 to -122.9 μm; p < 0.001). CMT remained stable over the 12-month follow-up period, with minimal fluctuations. Subretinal fluid (SRF) and intra retinal fluid (IRF) were present in 84.2% and 91.2% of eyes, respectively, decreasing to 5.3% and 7.0% at the time of switch (p < 0.001). In T2 phase, 22.8% and 21.1% exhibited SRF and IRF, respectively, at the end of the study.

Conclusion: Transitioning to biosimilar Ranibizumab (Razumab) after initial treatment with aflibercept in patients with DME preserved visual and anatomical benefits over a 12-month period, with only minor variations in SRF and IRF. These results underscore the efficacy of biosimilar Ranibizumab as a cost-effective option for managing DME.