Anbenitamab (KN-026) is a novel Fc-fused bispecific antibody targeting the human epidermal growth factor receptor 2 (HER2). It simultaneously binds to two non-overlapping extracellular domain epitopes of HER2 (domain IV, targeted by trastuzumab, and domain II, targeted by pertuzumab). This biparatopic binding mode induces superior receptor clustering and rapid degradation, leading to potent inhibition of downstream signaling pathways such as MAPK and PI3K. Anbenitamab demonstrates significant anti-tumor activity in HER2-positive or low-expressing breast, gastric, and gastroesophageal junction cancers, and effectively mediates antibody-dependent cellular cytotoxicity (ADCC).