Phase II Trial of Pembrolizumab in Recurrent or Metastatic HNSCC

Inclusion Criteria: 1. Histologically confirmed locally advanced, recurrent or metastatic squamous cell carcinoma of the head and neck that is considered incurable by local therapies 2. Measurable disease evaluated by RECIST criteria version 1.1 3. WHO performance status of 2 4. Life expectancy \>12 weeks 5. Aged ≥18 years of age 6. Adequate bone marrow function 7. Adequate renal function 8. Adequate liver function 9. Willing to use highly effective contraception for the duration of trial treatment and for 120 days after completion of treatment 10. Able to give informed consent, indicating that the patient has been informed of and understands the experimental nature of the study, possible risks and benefits, trial procedures, and alternative options 11. Willing and able to comply with the protocol for the duration of the study, including the treatment plan, investigations required and follow up visits Exclusion Criteria: 1. Patients with undifferentiated nasopharyngeal or sino-nasal cancers 2. Disease suitable for treatment with curative intent 3. Prior therapy with an anti-PD-1, anti-PD-L1 or anti-PD-L2 agent 4. Any investigational agents within 4 weeks prior to registration 5. Anti-cancer monoclonal antibody therapy within 4 weeks prior to registration 6. Chemotherapy, targeted small molecule therapy, or radiotherapy within 2 weeks prior to registration 7. Patients with concurrent or previous malignancy that could compromise assessment of the primary or secondary endpoints of the trial 8. Women who are pregnant or breast feeding 9. Grade 3 or 4 peripheral neuropathy 10. Any serious and/or unstable pre-existing medical, psychiatric or other condition that, in the treating clinician's judgment, could interfere with patient safety or obtaining informed consent 11. Active central nervous system (CNS) metastases and/or carcinomatous meningitis 12. Active hepatitis B or C infection 13. Immunocompromised patients (e.g. known HIV positive status) 14. Prior organ transplantation including allogenic stem-cell transplantation 15. History of (non-infectious) pneumonitis/interstitial lung disease that required steroids, or current pneumonitis/interstitial lung disease 16. Active infection requiring systemic therapy 17. Received a live vaccine within 30 days prior to registration 18. Diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other form of immunosuppressive therapy within 7 days prior to the first dose of trial treatment 19. Active autoimmune disease that might deteriorate when receiving an immune-stimulatory agent. 20. Current use of immunosuppressive medication (exceptions apply) Refer to section 7.2 for full list of eligibility criteria