Efficiency of anti-vascular endothelial growth factor drug switch in patients who did not respond to a series of bevacizumab injections

Purpose: To assess the effectiveness of switching anti-vascular endothelial growth factor (VEGF) agents in eyes with retinal pathologies that poorly respond to intravitreal bevacizumab injections. Methods: We compared central macular thickness (CMT) and VA between eyes with suboptimal responses to at least three bevacizumab injections that either continued with bevacizumab or switched to aflibercept or ranibizumab. Eyes were categorized into group D (DME), group N (neovascular age-related macular degeneration [nAMD]), and group A – all eyes (D and N plus eyes with retinal vein occlusion (RVO) or pseudophakic central macular edema [PCME]). Each group was further divided into those continuing bevacizumab (D1, N1, A1) or switching to aflibercept or ranibizumab (D2, N2, A2). Results: A total of 21 eyes were included in group D (8 in D1 and 13 in D2), 28 in group N (14 in N1 and 14 in N2), and 59 eyes in group A (25 in A1 and 34 in A2). In all eyes with treatment shift, CMT decreased: 38.5 (SD: 46.2), 92.6 (SD: 106.8), and 82.1 (SD: 115.6) microns in D2, N2, and A2, respectively. CMT difference was statistically significant between N1 versus N2 and between A1 versus A2 ( P = 0.025 and 0.004, respectively). No significant difference in VA was observed. Conclusion: Switching anti-VEGF agents appears anatomically beneficial in nonresponding eyes. Notably, the inclusion of a control group continuing bevacizumab despite poor response allows for a more reliable evaluation of treatment efficacy, addressing a key limitation of prior studies and contributing to the evidence-based rationale for agent switching.