ERBB2 and breast cancer: For instance, a mAb targeting this receptor, trastuzumab, in conjunction with granulocyte–macrophage colony-stimulating factor (GM-CSF), either with or without nelipepimut-S (NPS), a HER2-derived peptide vaccine, was evaluated within a randomized, multicenter, single-blinded, phase IIb trial encompassing high-risk breast cancer participants characterized by low levels of HER2 expression, including TNBC cases.