Olaparib and Durvalumab in Treating Participants With Metastatic Triple Negative Breast Cancer

PRIMARY OBJECTIVE: I. To assess the feasibility of completing Clinical Laboratory Improvement Act (CLIA) analytics on pre-treatment biopsy within a planned 4-week window for enrolled participants. SECONDARY OBJECTIVES: I. Assess safety and tolerability of the proposed therapy. II. Assess response to treatment. III. Determine the time to disease progression following study therapy. IV. Determine survival of participants enrolled on the study. EXPLORATORY OBJECTIVES: I. Examine response rates depending on tumor characteristics. II. Identify predictive biomarkers of sensitivity to therapy. III. Identify emerging mechanism of resistance to therapy tumor markers of emergence. IV. Determine changes in tumor cells induced by PARP inhibitors. V. Identify tumor markers suggestive of combinatorial therapy that could r overcome resistance to therapy. OUTLINE: Participants receive olaparib orally (PO) twice a day (BID) for 28 days in the absence of disease progression or unacceptable toxicity. Participants then receive olaparib PO BID on days 1-28 and durvalumab intravenously (IV) over 1 hour on day 1. Treatment repeats every 28 days for up to 12 courses in the absence of disease progression or unacceptable toxicity. Participants may continue on therapy beyond disease progression at the discretion of the investigator. After completion of study treatment, participants are followed up every 6 months for 1 year.