ERBB2 and breast cancer: To date, combinations of SG with other agents are of interest and are being evaluated in the metastatic setting for HER2-negative BC, including ICIs (NCT04468061; NCT04448886; NCT03424005) and poly (ADP-ribose) polymerase (PARP) inhibitors (SEASTAR, NCT03992131; NCT04039230) [47].