Antitumor activity and safety of pembrolizumab in patients (pts) with advanced squamous cell carcinoma of the head and neck (SCCHN): Preliminary results from KEYNOTE-012 expansion cohort.

Head and Neck Cancer
Session Type and Session Title: 
Oral Abstract Session, Head and Neck Cancer
Abstract Number: 


J Clin Oncol 33, 2015 (suppl; abstr LBA6008)
Tanguy Y. Seiwert, Robert I. Haddad, Shilpa Gupta, Ranee Mehra, Makoto Tahara, Raanan Berger, Se-Hoon Lee, Barbara Burtness, Dung T. Le, Karl Heath, Amy Blum, Marisa Dolled-Filhart, Kenneth Emancipator, Kumudu Pathiraja, Jonathan D. Cheng, Laura Q. Chow; The University of Chicago, Chicago, IL; Dana-Farber Cancer Institute, Boston, MA; H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL; Fox Chase Cancer Center, Philadelphia, PA; National Cancer Center Hospital East, Kashiwa, Japan; Sheba Medical Center, Tel HaShomer, Israel; Seoul National University Hospital, Seoul, South Korea; Yale Cancer Center, Yale School of Medicine, New Haven, CT; Sidney Kimmel Comprehensive Cancer Center at JHU, Baltimore, MD; Merck & Co., Inc., Kenilworth, NJ; Department of Medicine, Division of Oncology, University of Washington, Seattle, WA

Abstract Disclosures


Background: Pembrolizumab (MK-3475) is a humanized monoclonal antibody that blocks interaction of PD-1 with its ligands, PD-L1 and PD-L2, thereby promoting activity of tumor-specific effector T cells. KEYNOTE 012 (NCT01848834) had previously demonstrated clinical activity of pembrolizumab 10 mg/kg every 2 weeks in patients (pts) with recurrent/metastatic SCCHN enriched for PD-L1–positive tumors with a response rate of 20%. We now report on the larger SCCHN expansion cohort of KEYNOTE 012, irrespective of biomarker status using a 3-weekly fixed dose. Methods: Pts with advanced SCCHN irrespective of PD-L1 expression or HPV status received a fixed dose of 200 mg pembrolizumab, intravenously, every 3 weeks. Pts were evaluated every 8 weeks with radiographic imaging. The primary end point was overall response rate (ORR) per investigator assessment (RECIST 1.1). Secondary objectives included progression-free survival (PFS) and overall survival (OS). Adverse events (AEs) were assessed according to CTCAE v4. PD-L1 was assessed retrospectively by immunohistochemistry. Results: 132 pts with recurrent/metastatic SCCHN were enrolled. Mean (SD) age was 58.9 (9.7) years; 83.3% were male; 56.8% had ≥ 2 lines of therapy for recurrent disease. 73/132 pts (55.3%) remain on treatment. Out of 132 treated pts, 99 pts were available for this preliminary efficacy analysis with a post-baseline scan or discontinued therapy prior to the scan due to clinical progression or AE. ORR (confirmed and unconfirmed) per RECIST 1.1 was 18.2% (95% CI, 11.1-27.2) with 18 partial responses and 31.3% with stable disease. Biomarker analysis is ongoing and results will be presented. Drug-related AEs of any grade occurred in 47% of all enrolled pts, and drug-related grade ≥ 3 AEs occurred in 7.6%. The most common drug-related AEs ( ≥ 5%) of any grade were fatigue (12.1%), decreased appetite (6.8%), pyrexia (6.1%), and rash (5.3%). Conclusions: Pembrolizumab given at a fixed dose of 200 mg every 3 weeks was well tolerated and demonstrated a clinically meaningful ORR of 18.2% in pts with recurrent/metastatic SCCHN. Clinical trial information: NCT01848834