Pembrolizumab is a high-affinity monoclonal anti-PD1 antibody which showed antitumor activity in melanoma and NSCLC. In the KEYNOTE-012 (multi-center, nonrandomized Phase Ib HNSCC), Pembrolizumab was well tolerated and safe with no serious drug related AEs reported. About 51% (26/51) of patients had decreased tumor burden which was seen both in HPV (-) and HPV(+) HNSCC.