INCMGA00012 and Pelareorep for the Treatment of Metastatic Triple Negative Breast Cancer, IRENE Study

PRIMARY OBJECTIVES: I. To determine the efficacy of the combination of retifanlimab (INCMGA00012) and pelareorep for patients with metastatic triple negative breast cancer in the second and third line setting. II. To assess the safety, tolerability and feasibility of INCMGA00012 in combination with the oncolytic virus pelareorep for patients with metastatic triple negative breast cancer in the second and third line setting. SECONDARY OBJECTIVES: I. To assess progression free survival (PFS), overall survival (OS) and duration of response (DOR) in patients receiving INCMGA00012 in combination with the oncolytic virus pelareorep for patients with metastatic triple negative breast cancer in the second and third line setting. II. To assess quality of life measures. EXPLORATORY OBJECTIVES: I. To assess whether pre-treatment PD-L1 expression is associated with treatment outcomes. II. To determine if changes in T cell repertoire as measured by T-cell receptor (TCR) sequencing is predictive of treatment outcomes. OUTLINE: Patients receive pelareorep intravenously (IV) over 60 minutes on days 1, 2, 15, and 16. Patients also receive retifanlimab IV over 60 minutes on day 3. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 30 and 90 days, then every 6 months for up to 2 years.