957PD - Pembrolizumab after progression on platinum and cetuximab in head and neck squamous cell carcinoma (HNSCC): results from KEYNOTE-055

Date 08 October 2016
Event ESMO 2016 Congress
Session Head and neck cancers
Topics Head and Neck Cancers
Presenter Robert Haddad
Citation Annals of Oncology (2016) 27 (6): 328-350. 10.1093/annonc/mdw376
Authors R. Haddad1, T. Seiwert2, D.G. Pfister3, F. Worden4, S.V. Liu5, J. Gilbert6, N.F. Saba7, J. Weiss8, L.J. Wirth9, A. Sukari10, H. Kang11, M.K. Gibson12, E. Massarelli13, S. Powell14, A. Meister15, X. Shu15, J. Cheng15, J. Bauml16
  • 1Oncology, Dana-Farber Cancer Institute, Harvard Medical School, 02215 - Boston/US
  • 2Oncology, University of Chicago, 60637 - Chicago/US
  • 3Oncology, Memorial Sloan Kettering Cancer Center, New York/US
  • 4Oncology, University of Michigan Comprehensive Cancer Center, Ann Arbor/US
  • 5Oncology, Georgetown University Hospital, Washington/US
  • 6Oncology, Vanderbilt University School of Medicine, Nashville/US
  • 7Oncology, Winship Cancer Institute/Emory University, 30322 - Atlanta/US
  • 8Thoracic Oncology, Lineberger Comprehensive Cancer Center at the University of North Carolina, North Carolina/US
  • 9Oncology, Massachusetts General Hospital, Boston/US
  • 10Oncology, Karmanos Cancer Institute, Wayne State University, Detroit/US
  • 11Oncology, Johns Hopkins University School of Medicine, 21231 - Baltimore/US
  • 12Oncology, University Hospitals Case Medical Center, Cleveland/US
  • 13Oncology, The University of Texas MD Anderson Cancer Center, Houston/US
  • 14Oncology, Sanford Health, Sioux Falls/US
  • 15Medical Oncology, Merck & Co., Inc., Kenilworth/US
  • 16Oncology, University of Pennsylvania, Philadelphia/US

Abstract

Background

There are few treatment options in recurrent/metastatic (R/M) HNSCC after progression on platinum and cetuximab, and their efficacy is disappointing. During KEYNOTE-012, pembrolizumab, an anti–PD-1 antibody that blocks the interaction between PD-1 and its ligands, showed promising antitumor activity in R/M HNSCC. The efficacy and safety of pembrolizumab in patients with R/M HNSCC after progression on platinum and cetuximab are being investigated in the phase 2, nonrandomized KEYNOTE-055 (NCT02255097) study.

Methods

Pts receive pembrolizumab 200 mg every 3 weeks. Key eligibility criteria include R/M HNSCC resistant to platinum and cetuximab therapies, measurable disease, and ECOG PS 0-1. Primary outcomes include overall response rate (ORR, RECIST v1.1 by central imaging vendor) performed every 6-9 wk and safety. Adverse events (AEs) were graded using CTCAE, v4.0.

Results

Of the 171 pts who received ≥1 dose of pembrolizumab, median age was 61 y, 81% were male, 75% had ≥2 prior lines of therapy for metastatic disease. As of Jan 29, 2016, median follow-up time was 4 mo (range, 0-14). Treatment-related AEs (TRAEs) occurred in 102 (60%) pts, with 20 (12%) pts experiencing a grade 3-5 TRAE. 4 (2%) pts discontinued and 1 (1%) pt died because of a TRAE. AEs of special immunologic interest occurred in 35 (20%) pts; hypothyroidism (n = 23; grade 1 or 2) and pneumonitis (n = 3, grade 1 or 2; n = 1, grade 3; n = 1, grade 5) were the most common. When confirmed responses were evaluated, the ORR was 15% (PR, n = 25; 95% CI, 10%-21%) with a median duration of response of 7 mo (range, 0-8+); the stable disease rate was 22% (n = 37; 95% CI, 16%-29%). When unconfirmed and confirmed responses were evaluated, the ORR was 22% (CR, n = 2; PR, n = 35; 95% CI, 16%-29%) and the stable disease rate was 15% (n = 25; 95% CI, 10%-21%).

Conclusions

The clinically significant antitumor activity and safety profile of pembrolizumab in heavily pretreated R/M HNSCC shown here confirm findings from KEYNOTE-012 and support ongoing phase 3 trials in head and neck cancer. Further analyses of biomarker data including immunohistochemistry (PD-L1/PD-L2) and interferon gamma gene signatures will be presented.

Clinical trial identification

NCT02255097

Legal entity responsible for the study

Merck and Co., Inc.

Funding

Merck and Co., Inc.

Disclosure

T. Seiwert: Honoraria: Merck/MSD, Amgen, BMS, Astra Zeneca, Celgene, Serono. D.G. Pfister: Research funding: Merck, Exelixis, Medimmune, Astra Zeneca, Novartis Consulting or Advisory role: Boerhringer Ingelheim - Data Safety Monitoring Committee. S.V. Liu: Consulting Or Advisory Role: Genentech, Boehringer Ingleheim, Caris Life Sciences. J. Gilbert: Research Funding: AstraZeneca (Local PI), Merck, BMS, Steering Committee (unfunded). A. Sukari: Research funding: AstraZenca (PI), Merck (PI), MedImmune (PI), Karyopharm (PI), Boehringer Ingelheim (PI), VentiRx (PI), Mallinckrodt, Inc (PI), Acceleron Pharma (PI), Lilly (PI) Speakers Bureau: Novartis Oncology. E. Massarelli: Research funding: Merck, Bristol Myers Squibb, AstraZeneca, Medimmune Honoraria: Nektar Therapeutics Consulting or Advisory role: Nektar Therapeutics. S. Powell: Research Funding: Boerhringer Ingelheim - Data Safety Monitoring Committee. A. Meister, X. Shu, J. Cheng: Employee of Merck and Co, Inc. J. Bauml: Research funding: BMS, Merck, Astra Zeneca, Celgene,Venti-Rx Consulting or Advisory role: BMS, Merck, Celgene, Eisai. All other authors have declared no conflicts of interest.