Pembrolizumab Combined With Cetuximab for Treatment of Recurrent/Metastatic Head & Neck Squamous Cell Carcinoma

"Pembrolizumab (KEYTRUDA®; MK-3475) is a potent and highly selective humanized monoclonal antibody (mAb) of the immunoglobulin G4 (IgG4)/kappa isotype designed to directly block the interaction between PD-1 and its ligands, programmed cell death ligand 1 (PD-L1) and programmed cell death ligand 2 (PD-L2). This blockade enhances functional activity of the target lymphocytes to facilitate tumor regression and ultimately immune rejection.~Cetuximab (Erbitux®) binds specifically to the epidermal growth factor receptor (EGFR) on both normal and tumor cells, and competitively inhibits the binding of EGF and other ligands, such as transforming growth factor-alpha. Cetuximab can mediate antibody-dependent cellular cytotoxicity (ADCC), with in vitro assays and in vivo animal studies demonstrating that cetuximab inhibits the growth and survival of tumor cells expressing EGFR."