HuA21

HuA21 is a **humanized monoclonal antibody** targeting human epidermal growth factor receptor 2 (**HER2/ERBB2**), developed as a next-generation anti-HER2 therapeutic antibody based on the chimeric precursor chA21. Unlike trastuzumab, HuA21 binds to subdomain I of the HER2 extracellular domain and demonstrates strong antiproliferative effects against HER2-positive cancer cells—including those resistant to trastuzumab. It inhibits HER2 signaling by blocking HER2 activation and downstream PI3K/Akt and ERK1/2 pathways, induces antibody-dependent cell-mediated cytotoxicity (ADCC), and is efficiently internalized into cancer cells, suggesting applicability in developing antibody-drug conjugates (ADCs). HuA21 is under active clinical development as monotherapy and in combination with trastuzumab and chemotherapy, particularly for HER2-positive metastatic breast cancer and gastric cancer[1][3][5].

Brand names

HuA21HuA-21HuA 21

Other names

humanized chA21recombinant anti-HER2 humanized HuA21 monoclonal antibody