ABSTRACT
Biosimilars are biological medicinal products that are highly similar to an already licensed reference product in terms of quality, safety, and efficacy. BAT1706 is being developed by Bio-Thera Solutions, Ltd. as a proposed biosimilar candidate to bevacizumab reference product (Avastin®). Bevacizumab acts by specifically binding to vascular endothelial growth factor A (VEGF-A), and preventing the interaction of VEGF-A with its receptors on the surface of endothelial cells, then blocking the downstream signaling pathway mediated by ligand-receptor, and inhibiting endothelial angiogenesis, thus inhibiting tumor growth. Comprehensive analytical characterization studies incorporating orthogonal analytical techniques were performed to compare the in vitro functional activities of BAT1706 and Avastin®. BAT1706 and Avastin® showed highly similar binding activity to multiple VEGF-A isoforms and equivalent VEGF-A neutralizing activity, as well as inhibitory activity of VEGF receptor (VEGFR)-2 tyrosine kinase autophosphorylation. Both products exhibited similar binding of the Fcγ receptors and a lack of Fc-related effector functions such as antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). Overall, the results demonstrate that BAT1706 and Avastin® are highly similar in terms of in vitro functional activities.