Efficacy and safety of pembrolizumab in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC): Pooled analyses after long-term follow-up in KEYNOTE-012.

Abstract

6012Background: The PD-1 pathway is a key mechanism by which R/M HNSCC tumors evade immune surveillance. Pembrolizumab (pembro), an anti–PD-1 antibody, showed promising antitumor activity in R/M HNSCC in KEYNOTE-012 (NCT01848834). We present a pooled analysis of efficacy and safety of pembro after long-term follow-up in R/M HNSCC pts in this study. Methods: Pts had R/M HNSCC, measurable disease by RECIST v1.1, and ECOG PS 0-1. The initial (I) cohort enrolled PD-L1+ pts; expansion (E) cohort enrolled pts regardless of PD-L1 status. Pembro 10 mg/kg Q2W (I) or 200 mg Q3W (E) was given for 24 mo or until disease progression, unacceptable safety, or investigator/pt decision. Response was assessed every 8 wk. AEs were graded using CTCAE v4.0. Primary end point was ORR (RECIST v1.1) per central imaging vendor review. Secondary end points included PFS, OS, and duration of response (DOR). Pts who received ≥ 1 dose of pembro were included in these pooled analyses. Results: 192 R/M HNSCC pts were enrolled and receiv...