Engineered to block HER2 signaling with an increased affinity for CD16A polymorphisms while a decreased affinity for the inhibitory FcγRIIB (CD16B) receptor on immune effector cells, such as DCs, NK, monocytes, and macrophages,30 margetuximab has showed single-agent activity against heavily pretreated HER2+ BC patients in a phase I trial. This evidence concerns the gene ERBB2 and breast cancer.