UCLA B-13: A phase 1b trial evaluating the safety of ribociclib, tucatinib, and trastuzumab in patients with metastatic, HER2+ breast cancer and a multicenter, randomized, open-label, phase 2 study of preoperative treatment with ribociclib, trastuzumab, tucatinib, with or without fulvestrant versus docetaxel, carboplatin, trastuzumab, and pertuzumab in HR+/HR-, HER2+ breast cancer.