.Attributes Medicine, Posted online: thirteen September 2024 doi:10.1038/ s41591-024-03261-7In the non-randomized stage 3b/4 DESTINY-Breast12 study, trastuzumab deruxtecan (T-DXd) treatment of patients along with HER2+ sophisticated breast cancer cells and also energetic or secure human brain metastases presented constant intracranial activity as well as systemic efficiency of T-DXd.