Sitravatinib in Metastatic Breast Cancer

Inclusion Criteria: * Women or men age 18 and older * Metastatic or locally advanced inoperable breast cancer (beyond curative management) that is measurable according to RECIST 1.1 criteria. Note: Patients with bone-only disease are eligible if there is at least 1 lytic lesion that can be followed for response. * Tumor is estrogen receptor (ER) negative and progesterone receptor (PR) negative per the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) Guidelines of 2010. * Tumor is HER2neu negative per ASCO/CAP Guidelines of 2018 * Patient has archival tissue from metastatic or locally advanced breast cancer for the analysis of PTPN12 status * At least one prior line of chemotherapy with or without a PD-L1 or PD-1 antibody in the metastatic setting * Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2 (Karnofsky ≥ 60%) * Normal organ and marrow function as defined below: * Absolute neutrophil count \> 1000/mcL * Hemoglobin \> 11 g/dL * Platelets \> 100,000/mcL * Total bilirubin \< 1.5 X normal institutional limits * Aspartate aminotransferase (AST) / alanine aminotransferase (ALT) \< 2.5 X institutional ULN or ≤ 5.0 × ULN for patients with documented liver metastases. * Creatinine within normal institutional limits * Creatinine clearance ≥ 30 mL/min * Normal left ventricular ejection (LVEF) function defined as normal left ventricular wall motion and ejection fraction of ≥ 50%. * If patient has brain metastasis, documented treatment and stability for at least 30 days by scans and off steroids at the time of enrollment * Women of child bearing age and actively menstruating must have a negative pregnancy test prior to starting study treatment. * If sexually active in a way that could lead to pregnancy, participant must agree to use a highly effective method of birth control starting at the time of informed consent and continuing throughout the study and for at least 3 months after the final dose of sitravatinib. * Ability to understand and the willingness to give informed consent Exclusion Criteria: * Uncontrolled hypertension defined as systolic blood pressure \> 150 and/or diastolic blood pressure \> 100, on two or more occasions within 30 days prior to enrollment. * Imaging suggestive of Lymphangitic carcinomatosis in the lung, or use of home oxygen * Untreated brain metastases. * Women who are pregnant or nursing * Concurrent metastatic disease of another tumor type * Impairment of gastrointestinal (GI) function or GI disease that may significantly alter the absorption of sitravatinib * History of stroke, pulmonary embolus (PE), or myocardial infarction (MI) * Known proteinuria of ≥ 2 g urinary protein/24 h * HIV-positive participants * History of Hepatitis C or Hepatitis B infection * History of congestive heart failure (CHF), and/or LVEF less than 50% * Concurrent use of medications that prolong QTc (listed in Section 9, Table 11). These medications need to be discontinued at least 2 weeks prior to starting study treatment. * Concurrent medical condition that, in the sole judgment of the principal investigator, would make the patient inappropriate for trial participation.