Aflibercept and Faricimab Equipotently Restore Endothelial Barrier Function

Purpose: To study the biological effects of aflibercept and faricimab on vascular endothelial growth factor (VEGF)-A165-induced vascular permeability in an in vitro head-to-head comparison using human-derived endothelial cells. Methods: This in vitro study used a human umbilical vein endothelial cell (HUVEC)-based model, in which cells were exposed to VEGF-A165, followed by the addition of aflibercept (1.7 nM) or faricimab (2.0 nM) either simultaneously (preventive) or 24 hours later (therapeutic/rescue). Cell-layer permeability was measured on the xCELLigence platform, global transcriptomic changes by RNA sequencing, and VEGF-A165-induced release of angiogenesis-related proteins by electrochemiluminescence immunoassay. Results: Concurrent addition of aflibercept or faricimab prevented VEGF-A165-triggered increase of HUVEC cell-layer permeability (P = 0.0005). In the therapeutic/rescue setting, either drug temporally improved the cell-layer integrity (P = 0.0001). Aflibercept was non-inferior to faricimab in both the preventive (P < 0.0001) and therapeutic/rescue (P < 0.0001) settings. Aflibercept and faricimab comparably downregulated VEGF-A165-induced angiogenesis-related genes. Aflibercept and faricimab equipotently suppressed or reversed VEGF-A165 upregulation of ANGPT2 gene expression and angiopoietin-2 (ANG2) protein in culture supernatant. VEGF-A165-driven TEK gene expression and soluble Tie2 increase in culture supernatant was reversed with aflibercept and faricimab in both settings. Conclusions: In this in vitro model of VEGF-A165-driven vascular permeability, additional blockade of ANG2 with faricimab did not improve endothelial barrier integrity beyond VEGF-A165 blockade alone with aflibercept, despite significant upregulation of ANG2 expression after VEGF-A165 stimulation. Aflibercept and faricimab were comparable in maintaining or restoring endothelial barrier function and thereby vascular integrity, mainly attributable to inhibition of VEGF-A165 binding to its receptor.