The goal of this study is to assess whether treatment with bavituximab shifts the cellular balance to favor an effective T-cell mediated antitumor response resulting to an enhanced response in conjunction with pembrolizumab. Bavituximab is a chimeric (human/mouse) monoclonal antibody that targets phosphatidylserine (PS). PS facilitates the recognition and clearance of dying cells, triggering the release of immunosuppressive cytokines and inhibiting the production of proinflammatory cytokines. Within the tumor microenvironment, PS polarizes macrophages toward an immunosuppressive phenotype. Bavituximab upregulates the adaptive T cell-mediated response through crosslinking FCRγ and dampening of signaling between PS and PS receptors on immunosuppressive myeloid-derived suppressor cells.~Thus, the investigators are doing this phase II single arm study to determine if bavituximab could potentially synergize with PD-1 inhibitor therapy to generate an effective anti-tumor immune response in patients with recurrent/metastatic squamous cell head and neck cancer (HNSCC) who progressed on a PD-1 inhibitor.
This phase II single arm study is being done to determine if bavituximab could potentially synergize with PD-1 inhibitor therapy to generate an effective anti-tumor immune response in patients with recurrent/metastatic squamous cell head and neck cancer (HNSCC) who progressed on a PD-1 inhibitor.