– Anbenitamab (KN-026) is a bispecific antibody targeting extracellular domains II and IV of human HER2, blocking both ligand-dependent and independent signaling pathways. Its IgG1 Fc fragment activates FcRγIIIa, triggering strong antibody-dependent cell-mediated cytotoxicity (ADCC) and suppressing tumor cell growth. Anbenitamab shows promise for research in HER2-positive metastatic breast cancer (MBC) [1][2].