T-DXd With or Without Bevacizumab for HER2-low Breast Cancer With Brain Metastasis

This is a Phase II, open-label, multicenter, randomized controlled trial (THUMB study) comparing the efficacy and safety of trastuzumab deruxtecan (T-DXd) with or without bevacizumab for HER2-low expressing breast cancer with brain metastases. Patients receiving treatment in the metastatic setting must not have received more than 3 lines of therapy (HR-positive patients must have received a CDK4/6 inhibitor). Participants are randomized in a 1:1 ratio to receive treatment with T-DXd combined or not combined with bevacizumab.