This invention relates to a pharmaceutical composition that comprises a first molecule that specifically binds HER2/neu and a second molecule that specifically binds a cell-surface receptor (or its ligand) that is involved in regulating an immune checkpoint (or the ligand thereof). The invention particularly relates to the embodiment wherein the second molecule binds to PD-1. The invention also relates to the use of such pharmaceutical compositions to treat cancer and other diseases.本發明涉及藥物組合物,其包括特異性結合HER2/neu的第一分子和參與調節免疫檢查點(或其配體)的、特異性結合細胞表面受體(或其配體)的第二分子。本發明尤其涉及其中第二分子結合PD-1的實施方式。本發明也涉及這類藥物組合物治療癌症和其他疾病的用途。