Carboplatin With or Without Atezolizumab in Treating Patients With Stage IV Triple Negative Breast Cancer

Inclusion Criteria

• Patients must provide informed written consent
• Eastern Cooperative Oncology Group (ECOG) performance status 0-1
• Clinical stage IV ER, PR, HER2 negative invasive mammary carcinoma, previously documented by histological analysis and that meets the following criteria:
• HER2 negativity is defined as any of the following by local laboratory assessment: In-situ hybridization (ISH) non-amplified (ratio of HER2 to CEP17 = 1500/mm^3 (without granulocyte colony-stimulating factor [G-CSF] support within 2 weeks prior to cycle 1, day 1)
• Lymphocyte count >= 500/uL
• Platelet count >= 100, 000/mm^3 (without transfusion within 2 weeks prior to cycle 1, day 1)
• Hemoglobin >= 9.0 g/dL
• Patients may be transfused or receive erythropoietic treatment to meet this criterion
• Calculated creatinine clearance >= 30 mL/min using the Calvert Formula
• Bilirubin = = 60 years
• Age = 2 weeks prior to randomization
• Known central nervous system (CNS) disease, except for treated asymptomatic CNS metastases, provided all of the following criteria are met: measurable disease outside the CNS, only supratentorial metastases allowed (i.e., no metastases to midbrain, pons, medulla, or spinal cord), no evidence of progression or hemorrhage after completion of CNS-directed therapy, no ongoing requirement for dexamethasone as therapy for CNS disease (anticonvulsants at a stable dose are allowed), no stereotactic radiation within 7 days or whole-brain radiation within 14 days prior to randomization
• Leptomeningeal disease
• Uncontrolled tumor-related pain: patients requiring narcotic pain medication must be on a stable regimen at registration; symptomatic lesions (e.g., bone metastases or metastases causing nerve impingement) amenable to palliative radiotherapy should be treated prior to randomization; patients should be recovered from the effects of radiation; there is no required minimum recovery period; asymptomatic metastatic lesions whose further growth would likely cause functional deficits or intractable pain (e.g., epidural metastasis that is not presently associated with spinal cord compression) should be considered for loco-regional therapy if appropriate prior to randomization
• Uncontrolled hypercalcemia (> 1.5 mmol/L ionized calcium or calcium > 12 mg/dL or corrected serum calcium > upper limit of normal [ULN]) or symptomatic hypercalcemia requiring continued use of bisphosphonate therapy; patients who are receiving denosumab must discontinue denosumab use and replace it with a bisphosphonate instead while on study; patients receiving a bisphosphonate for skeletal metastases are not excluded and can continue treatment
• Malignancies other than triple negative breast cancer (TNBC) within 5 years prior to randomization, with the exception of those with a negligible risk of metastasis or death and treated with expected curative outcome (such as adequately treated carcinoma in situ of the cervix or basal or squamous cell skin cancer)
• Concurrent anti-cancer therapy (chemotherapy, radiation therapy, surgery, immunotherapy, hormonal therapy, biological therapy) other than the ones specified in the protocol; any other investigational drugs should be discontinued 2 weeks prior to the first dose of study medication
• GENERAL MEDICAL EXCLUSION CRITERIA
• Women only: pregnancy or lactation
• Evidence of significant uncontrolled concomitant disease that in the opinion of the investigator could affect compliance with the protocol or interpretation of results, including significant liver disease (such as cirrhosis, uncontrolled major seizure disorder, or superior vena cava syndrome)
• Significant cardiovascular disease, such as New York Heart Association (NYHA) cardiac disease (class II or greater), myocardial infarction within 3 months prior to randomization, unstable arrhythmias, or unstable angina; patients with a known left ventricular ejection fraction (LVEF) < 40% will be excluded; patients with known coronary artery disease,