Carboplatin, Nab-Paclitaxel and Pembrolizumab for Metastatic Triple-Negative Breast Cancer

Inclusion Criteria: * Subjects must have histologically or cytologically confirmed metastatic triple negative breast cancer * Subjects must have received no more than 2 prior therapies for this disease * ECOG Performance Status 0-1 * Subjects must have normal organ and marrow function as defined below: * Hemoglobin ≥ 10.0 g/dl * Absolute neutrophil count ≥ 1,000/μL * Platelet count ≥ 100,000/μL * Total bilirubin within normal institutional limits * AST (SGOT) ≤ 2.5 X institutional upper limit of normal * ALT (SGPT) ≤ 2.5 X institutional upper limit of normal * Serum creatinine ≤ 1.5 normal institutional limits * Life expectancy of 12 weeks or more * Subjects must have the ability to understand and the willingness to sign a written informed consent document * Subjects must have measurable disease per RECIST v1.1 * Subjects must be willing to undergo a preliminary biopsy of a metastatic focus for research purposes. A second post-treatment biopsy will be offered but will not be mandated Exclusion Criteria: * Prior treatment toxicities have not resolved to ≤ Grade 1 according to NCI CTCAE Version 4.0 (except for alopecia and neuropathy) * Subjects receiving any other investigational agents * Subjects with radiographically stable treated brain metastases are eligible but must not have been on steroid therapy for at least 4 weeks * History of allergic reactions attributed to compounds of similar chemical or biologic composition to nab-paclitaxel, carboplatin, pembrolizumab, or other agents used in this study * Subjects with uncontrolled intercurrent illness including, but not limited to ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * Pregnant or breastfeeding women are excluded from this study * Patients with conditions requiring immunosuppressive medications or chronic infections (including HIV infection, hepatitis B and C) * Patients with chronic autoimmune disease * Patients with prior therapy with antibodies that modulate T-cell function (e.g., anti-PD-1, anti-PD-L1) * Patients with evidence of active, non-infectious pneumonia * Patients active infection requiring intravenous systemic therapy * Patients with known psychiatric or substance abuse disorders that would interfere with cooperation with requirements of the trial * Patients who have received a live vaccine within 30 days prior to the first dose of pembrolizumab * Patients with a known additional malignancy that is progressing or requires active treatment (within the last 5 years). Exceptions: basal cell carcinoma of the skin, squamous cell carcinoma of the skin or in situ cervical cancer that has undergone potentially curative therapy * Patients who have received monoclonal anti-cancer antibody within 4 weeks of first dose of study drugs * Patients who have received chemotherapy, small molecule targeted therapy or radiation within the 2 weeks of first dose of study drugs * Patients who have participated in MK-3475 Merck studies * Patients with carcinomatous meningitis