Abstract
PURPOSE: To analyze morphological and functional response after administration of a single dose of ranibizumab in eyes under treat&extend aflibercept in neovascular age related macular degeneration (nAMD). Additionally, we aimed to identify predictive factors in anti-vascular endothelial growth factor (VEGF) treatment. METHODS: A total of 115 patients (133 eyes; 34 male, 81 female, m:f = 1:2.4) with a mean age of 79.9 ± 8.3 years at baseline (BSL) were included in this retrospective analysis. All eyes had received aflibercept treatment for nAMD before BSL and were subsequently administered a single dose of intravitreal ranibizumab. Data of two visits pre and two visits after BSL were evaluated and compared. Primary outcome measure was the mean change in central macular thickness (CMT, µm). CMT-changes between BSL and the next follow-up visit (V4) were roughly divided into decrease (<-10µm), equal (-10 to +10 µm) or increase (> +10µm). We also assessed changes in best-corrected visual acuity (BCVA) and identified influencing factors on CMT and BCVA using linear mixed models (LMM). RESULTS: No significant differences in CMT and BCVA were observed over the visits (p > 0.05). Factors influencing CMT included prior anti-VEGF injections (p < 0.001), the time interval between BSL and visit 4 (p < 0.001), and patient age (p = 0.032). The number of prior anti-VEGF injections significantly influenced BCVA (p = 0.003). After a single administration of ranibizumab, in 19.5% (n = 26) of eyes CMT decreased, in 21.8% of eyes (n = 29) CMT increased and in 36.8% of eyes (n = 49) it remained equal. CONCLUSION: Our study indicates that changes in CMT are affected by age, the number of previous injections, and the time interval between visits. These biomarkers may offer valuable insights for future research on switching anti-VEGF drugs to optimize treatment strategies for nAMD. A single dose treatment switch to ranibizumab yielded non-inferior outcomes.