.Attributes Medicine, Posted online: 13 September 2024 doi:10.1038/ s41591-024-03261-7In the non-randomized period 3b/4 DESTINY-Breast12 research, trastuzumab deruxtecan (T-DXd) treatment of individuals along with HER2+ sophisticated bosom cancer cells and energetic or dependable mind metastases showed steady intracranial activity and also systemic efficiency of T-DXd.