ZW25 can potentially mediate its therapeutic effect on low HER2-expressing tumors by the bi-paratopic targeting of HER2 resulting in:
Enhanced effector function-mediated cytotoxicity including ADCC, CDC and ADCP as a result of increased binding/decoration of the tumor cells by ZW25. Enhanced phagocytosis and presentation of HER2 antigen may also lead to increased immune targeting of the tumors;
Increased blockade of ligand-dependent and ligand-independent tumor growth; and
Increased ZW25-mediated HER2 internalization, which reduces HER2-mediated signaling and results in tumor growth inhibition and apoptosis.