Aflibercept-Refractory Neovascular Age-related Macular Degeneration: Response to Switching to Ranibizumab

Purpose: The aim of this study was to evaluate the effect of switching from aflibercept to ranibizumab in patients with aflibercept refractory neovascular age-related macular degeneration (nAMD) and to identify predictive factors for switch response. Methods: Retrospective chart review including eyes with nAMD, refractory to monthly intravitreal aflibercept during 6 months or more and that were switched to ranibizumab. Outcome measures included changes in visual acuity (VA), intra- (IRF) and subretinal fluid (SRF), pigment epithelial detachment (PED) and central retinal thickness (CRT), evaluated at 6 months before switch (T1), at the switching timepoint (T2), and 3 months post-switch (T3). Results: The study included 32 eyes from 26 patients. There was an increase of CRT from T1 to T2, which decreased after switch from T2 to T3. Evaluating the different compartments, a significant slope (change per month before and after switching) change was found for PED height (p=0.02), for the subretinal fluid (p=0.01) and for the neuroretinal thickness as a measure for intraretinal fluid (p=0.03). No significant change was found for VA. Predictive factors for better morphological switch response included a steeper slope before switch (worsening between T1 to T2), thicker measurement of the parameter at T2, male gender, shorter treatment before switch and fewer preceding injections. No association with preceding switch was found. Conclusion: Aflibercept-refractory nAMD benefits from switching to ranibizumab, particularly in cases of preceding worsening. Drug tolerance to aflibercept is suspected responsible. Thus, appropriate clinical decision might be facilitated by this knowledge, supposedly with a visual benefit for the patients