.Attributes Medicine, Posted online: thirteen September 2024 doi:10.1038/ s41591-024-03261-7In the non-randomized period 3b/4 DESTINY-Breast12 study, trastuzumab deruxtecan (T-DXd) treatment of individuals with HER2+ innovative breast cancer and energetic or even steady brain metastases presented steady intracranial activity as well as wide spread efficiency of T-DXd.