Clinical Research Directory

Inclusion Criteria: * Able to understand and willing to give an informed consent for the study. * Males or females aged 18 to 80 years. * Have an Eastern Co-operative Oncology Group (ECOG) performance status less than equal to 1. * Pathologically (histologically or cytologically) confirmed, non-metastatic diagnosis of squamous cell carcinoma of head and neck (SCCHN). * Achievement of major pathological reaponse (MPR) after surgery with neoadjuvant immunotherapy combined chemotherapy. * Adequate bone marrow, liver, and renal function: Absolute neutrophil count ≥ 1.5 × 10\^9/L, hemoglobin ≥ 9.0g/dL, platelets ≥100000/μL; ALT and AST \< 2.5× upper limit of normal (ULN), total bilirubin ≤ 1.5×ULN； Creatinine clearance ≥ 60 ml/min； APTT≤ 1.5×ULN. Exclusion Criteria: * Participant has metastatic/unresectable SCCHN. * Have an active autoimmune disease requiring systemic treatment or a documented history of clinically severe autoimmune disease. * With active hepatitis B or C, or known history of positive HIV test, or acquired immunodeficiency syndrome. * With interstitial pneumonitis, non-infectious pneumonitis, active pulmonary tuberculosis, or history of pulmonary tuberculosis infection that were not controlled by treatment. * With active infection requiring systemic therapy. * Received any investigational drug within 4 weeks prior to the first dose, or concurrently enrolled in another clinical trial. * Any other factors that are not suitable for inclusion in this study judged by investigators.