Predictors of response to bevacizumab monotherapy in polypoidal choroidal vasculopathy: a 12-month retrospective study

Abstract

Background: To identify baseline predictors of anatomical response after intravitreal bevacizumab in polypoidal choroidal vasculopathy (PCV) and to evaluate anatomical and visual outcomes over 12 months. Methods: This retrospective study included 81 eyes with PCV treated with three consecutive monthly intravitreal bevacizumab injections. Patients were classified as good or poor responders based on optical coherence tomography (OCT) findings at month 3. Baseline demographic, clinical, and imaging parameters were compared between groups, and predictors of poor response were identified using multivariable regression. Visual acuity (VA), central retinal thickness (CRT), subretinal fluid (SRF), and pigment epithelial detachment (PED) height were analyzed within and between groups through month 12. Results: Forty eyes (49.4%) were poor responders and 41 (50.6%) were good responders. Greater baseline SRF height and thinner SFCT were independent predictors of poor response (RR per 100 μm: 1.27 and 0.71 respectively; AUC = 0.74). Good responders showed significant VA improvement (0.64 ± 0.08 vs. 0.48 ± 0.06 logMAR, p < 0.001) and CRT reduction (419.5 ± 24.3 vs. 285.5 ± 14.1 μm, p < 0.001) at month 3, and these were maintained at month 12. Among good responders, 75% continued bevacizumab injections (non-switch group) and sustained favorable outcomes. In contrast, 86% of poor responders switched to other medications (switch group), achieving significant VA gain, CRT reduction, and further SRF with PED reduction by month 12. The non-switch group required fewer injections (5.8 ± 2.5 vs. 7.8 ± 3.0 injections; p < 0.001) and achieved longer treatment intervals (11.7 ± 9.0 vs. 7.8 ± 3.0 weeks; p = 0.046) than the switch group. Conclusions: Approximately half of PCV eyes demonstrated a favorable response to bevacizumab monotherapy. Baseline SRF height and SFCT were significant predictors of treatment response. Early assessment after three monthly bevacizumab injections allowed for the differentiation between relatively mild and a more severe disease requiring more frequent and sustained anti-VEGF injections. Switching of anti-VEGFs was associated with improved outcomes in poor responders.