Key Inclusion Criteria:  Individual has provided informed consent Individual is willing and able to comply with clinic visits and procedures outlined in the study protocol Individuals must have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 Laboratory measurements, blood counts: Adequate hemoglobin, neutrophil, and platelet counts Laboratory measurements, renal function: Adequate creatinine and liver function tests Male and female individuals of childbearing potential who engage in heterosexual intercourse must agree to use protocol-specified method(s) of contraception Measurable disease according to RECIST, version 1.1. Previously irradiated lesions can be considered as measurable disease only if disease progression has been unequivocally documented at that site since radiation Individuals must be willing to provide baseline tumor tissue from a core or excisional biopsy (fine needle aspirate is not adequate). A newly obtained biopsy (within 90 days prior to study treatment start) is strongly preferred, but an archival sample (within 6 months prior to study treatment start) is acceptable. Individuals will also be requested to consent to a mandatory on-treatment tumor biopsy unless not feasible as determined by the investigator and discussed with the sponsor Individuals previously untreated for unresectable locally advanced or mTNBC that is histologically or cytologically confirmed based on the most recent analyzed biopsy or other pathology specimen, as defined by the most recent American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guideline Individuals whose tumors do not express programmed cell death ligand 1 (PD-L1), as determined by an approved test according to local regulations Prior systemic treatment for neoadjuvant and/or adjuvant therapy and/or curative intent radiation therapy is permitted if completed at least 6 months prior to enrollment.  Note: Maintenance therapies are not counted as separate lines of therapy.  Key Exclusion Criteria:  Positive serum pregnancy test Breastfeeding female Active central nervous system (CNS) disease. Individuals with asymptomatic and stable, treated CNS lesions (radiation and/or surgery and/or other CNS-directed therapy who have not received corticosteroids for at least 4 weeks) are allowed Red blood cell (RBC) transfusion dependence, defined as requiring more than 2 units of packed RBC transfusions during the 4-week period prior to screening. RBC transfusions are permitted during the screening period and prior to enrollment to meet the hemoglobin inclusion criteria History of hemolytic anemia, autoimmune thrombocytopenia, or Evans syndrome in the last 3 months Known hypersensitivity to any of the study drugs, the metabolites, or formulation excipient Prior treatment with cluster of differentiation 47 (CD47) or signal regulatory protein alpha-targeting agents Current participation in another interventional clinical trial Known inherited or acquired bleeding disorders Significant disease or medical conditions, as assessed by the investigator and sponsor, that would substantially increase the risk-benefit ratio of participating in the study Known active or chronic hepatitis B or C infection or human immunodeficiency virus infection in medical history) Prior anticancer therapy including but not limited to chemotherapy, immunotherapy, or investigational agents within 4 weeks prior to magrolimab is not permitted.  Note: Other protocol defined Inclusion/Exclusion criteria may apply.