RecruitingPhase 2Drug trialSacituzumab Govitecan +/- Pembrolizumab in Metastatic TNBCThis research study involves testing the safety and efficacy of an investigational intervention for patients with triple-negative breast cancer (TNBC) that has spread, or metastasized, to other parts the body and is PD-L1-negative. The names of the study interventions involved in this study are: * Sacituzumab govitecan (Trodelvy™;IMMU-132) * Pembrolizumab (Keytruda®; MK-3475)