One more bispecific, humanized IgG1 antibody which is under investigation is zenocutuzumab (MCLA-128), which functions through two independent mechanisms of action: inhibition of HER2–HER3 signalling and elimination of tumour cells by using ADCC. MCLA-128 functions by using a ‘dock and block’ mechanism whereby a single arm of your antibody binds https://www.directivepublications.org/journal-of-clinical-breast-cancer/