Window Study of Intratumoral Mitazalimab in Breast Cancer (WINIT-BC)

The goal of this clinical trial is to study the safety, feasibility, histologic and immunological effects of Mitazalimab, a CD40 agonistic antibody, when administered either alone or in combination with PD-1 inhibition prior to surgical resection. The investigator hypothesizes that preoperative administration of CD40 agonist with or without PD-1 inhibitor intratumorally will demonstrate an acceptable safety profile, will not result in an unplanned delay in surgery, and will lead to increased immune activation. Subjects will receive a single intratumoral dose of CD40 agonist with or without PD-1 inhibitor 7 or more days prior to surgery and will be followed for safety, feasibility, immune, and pathologic responses.