Another bispecific, humanized IgG1 antibody that's underneath investigation is zenocutuzumab (MCLA-128), which acts by way of two unbiased mechanisms of action: inhibition of HER2–HER3 signalling and elimination of tumour cells via ADCC. MCLA-128 functions through a ‘dock and block’ mechanism whereby a single arm from the antibody binds HER2 area https://www.directivepublications.org/journal-of-clinical-breast-cancer/