Surufatinib Combined with Envolizumab As Second-line Treatment for Recurrent/Metastatic HNSCC

This study is a prospective,open-label,single-arm clinical trial to evaluate the efficacy and safety of s Surufatinib combined with envolizumab as second-line treatment of recurrent/metastatic head and neck squamous cell carcinoma . envolizumab: 300 mg subcutaneously every 3 weeks (Q3W); Surufatinib : 200 mg orally within 1 hour after breakfast, once daily continuously every 3 weeks as a treatment cycle until intolerable toxicity or disease progression. If any ≥ Grade 2 treatment-related adverse event occurs during treatment, the dose may be adjusted to 100 mg according to the investigator 's clinical assessment. The study is divided into 3 period: Screening, Treatment, and Follow-up. The treatment period is a 3-week treatment cycle. During the treatment period, tumor assessment will be performed by imaging method every 6 weeks (± 7 days) until disease progression (RECIST 1.1) or death (during treatment) or intolerable toxicity. The tumor treatment and survival status after disease progression should be recorded. Safety measures included: adverse events, laboratory tests, vital signs, and changes in electrocardiogram and cardiac ultrasound.