Figure 3.

Molecular masses of aflibercept-VEGF-A and bevacizumab-VEGF-A complexes. (A) Using a 1:2 molar ratio of aflibercept to VEGF 165, discrete peaks were observed at 17 mL and 14.5 mL. In contrast, a 1:2 molar ratio of bevacizumab to VEGF 165 revealed a heterogeneous multimeric complex that ranged in molar mass from 370 kDa to 2000 kDa.⁷⁴ (B) One milligram of a preformed complex of aflibercept (VEGF Trap) and VEGF 165 or bevacizumab and VEGF 165 were injected into the left ventricle of 2- to 3-month-old C57bl6 mice. After 10 minutes, the mice were killed, and their kidneys were processed for immunocytochemistry, using an antihuman Fc reporter antibody to the human Fc moiety present on both aflibercept and bevacizumab. Significant staining was observed in the glomeruli of bevacizumab/VEGF-treated mice but not in the glomeruli of aflibercept/VEGF-treated mice (white arrows).⁷⁴ Reprinted with permission from Rudge JS, Holash J, Hylton D, et al. VEGF Trap complex formation measures production rates of VEGF, providing a biomarker for predicting efficacious angiogenic blockade. Proc Natl Acad Sci U S A. 2007;104(47):18363–18370.⁷⁴ Copyright 2007 National Academy of Sciences, USA.

Abbreviations: RIU, refractive index units; VEGF, vascular endothelial growth factor.