A Single-arm Phase II Trial of SAcituzumab Govitecan and Trastuzumab for HER2+ Metastatic Breast Cancer After Trastuzumab dEruxtEcaN (SATEEN)

This is an open-label, multi-center, single-arm phase II trial to evaluate the safety and effectiveness of sacituzumab govitecan with trastuzumab (Herceptin, Herceptin Hylecta, or trastuzumab biosimilar) in metastatic HER2+ breast cancer. Participants may receive a biosimilar drug to trastuzumab, which is a nearly identical "copycat" of an original drug that is manufactured by a different company The U.S. Food and Drug Administration (FDA) has not approved sacituzumab govitecan for Human-epidermal growth receptor 2-positive (HER2+) breast cancer, but it has been approved for triple negative breast cancer and hormone receptor positive but HER2-negative breast cancer. The U.S. FDA has approved Trastuzumab to be administered as an IV (intravenous) or subcutaneous (injection under the skin) for HER2+ breast cancer. The research study procedures include screening for eligibility, blood tests, Computerized Tomography (CT) scans or Magnetic Resonance Imaging (MRI) scans, biopsies, study treatment visits, echocardiograms and/or Multigated Acquisition (MUGA) scans. It is expected that about 40 people will take part in this research study. Gilead Sciences Inc. is supporting this research study by providing funding for the trial as well as one of the study drugs, sacituzumab govitecan.