Pembrolizumab in Combination With CRT for LA-SCCHN

This is a single-arm, multi-site, open-label trial of pembrolizumab (MK-3475) used in combination with standard, cisplatin-based, definitive chemoradiotherapy (CRT) in patients with stage III-IVB squamous cell carcinoma of the head and neck (SCCHN). Approximately 39 patients with Stage III-IVB SCCHN will be enrolled to evaluate both the safety and efficacy of this novel combination. Subjects will not be randomized and will all receive the study treatment. Treatment will consist of a loading dose of pembrolizumab 200 mg IV given 7 days prior to initiation of CRT (day-7). CRT with cisplatin 40 mg/m2 IV weekly and head and neck radiation at 70 Gy fractionated at 2 Gy once daily over 35 days, will begin on day 1. CRT will end on approximately day 46-50. Pembrolizumab 200 mg IV will continue following CRT in an adjuvant fashion starting on day 57 for an additional 5 doses, as tolerated, through day 141. Subjects will be evaluated for response following treatment.