SGT-53, Carboplatin, and Pembrolizumab for the Treatment of Metastatic Triple Negative Inflammatory Breast Cancer

PRIMARY OBJECTIVES: I. To assess feasibility of transferrin receptor-targeted liposomal p53 cDNA (SGT-53) with carboplatin and pembrolizumab in metastatic triple negative inflammatory breast cancer (IBC) with a Combined Positive Score of \>=10 in PD-L1 expression, as measured by rate of successful administration. II. To assess preliminary activity of SGT-53 with carboplatin and pembrolizumab in metastatic triple negative IBC with a Combined Positive Score of \>= 10 in PD-L1 expression, as measured by clinical benefit rate (complete response \[CR\] + partial response \[PR\] + stable disease \[SD\] \>= 6 months using Response Evaluation Criteria in Solid Tumors \[RECIST\] criteria version \[v\] 1.1). SECONDARY OBJECTIVE: I. To assess the safety and tolerability of the combination of SGT-53 with carboplatin and pembrolizumab in patients with metastatic triple negative IBC with a Combined Positive Score of \>= 10 in PD-L1 expression, as measured by Common Terminology Criteria for Adverse Events (CTCAE) v 5.0. OUTLINE: Patients receive SGT-53 intravenously (IV) over 90-120 minutes on days 1, 8, and 15, pembrolizumab IV over 30 minutes on day 3, and carboplatin IV over 30-60 minutes on day 3. Treatment repeats every 21 days for up to 35 cycles in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 28 days, every 3 months for 2 years, and then every 6 months for 5 years from the start of study treatment.