• Patients with histologically confirmed post-surgical recurrent/metastatic or locally advanced inoperable oral squamous carcinoma with measurable lesions (spiral CT scan ≥ 10 mm, meeting RECIST 1.1 criteria).

• No prior treatment with any systemic antineoplastic agent, prior adjuvant or neoadjuvant therapy (other than PD-1/PDL-1 monoclonal antibody) is allowed, provided that it was completed at least 4 weeks prior to the first dose of study drug and all associated toxic events have returned to normal or to grade I or below as defined by CTCAE 4.03 classification.

• An ECOG score of 0 or 1.

• Expected survival of ≥ 12 weeks.

• Normal function of major organs within 2 weeks prior to treatment, i.e. meeting the following criteria.

⁃ Bone marrow function: hemoglobin ≥ 100gg/L, white blood cell count ≥ 4.0\*10\^9/L or neutrophil count ≥ 2.0\*10\^9/L and platelet count ≥ 100\*10\^9/L without transfusion or with colony-stimulating factor support therapy.

⁃ Liver: serum total bilirubin level ≤ 1.5 times the upper limit of normal, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 1.5 times the upper limit of normal.

⁃ Renal: blood creatinine level less than 1.5 times the upper limit of normal or creatinine clearance ≥ 60 ml/min and urea nitrogen ≤ 200 mg/L. Urine protein \<+, if urine protein + then total 24 hour protein must be \<500mg.

⁃ Blood glucose: within normal range and/or with diabetic patients on treatment but with stable blood glucose control.

⁃ Pulmonary function: baseline FEV1 of at least 2L, if baseline FEV1 \< 2L, FEV1 \>800ml is expected after surgery as assessed by a surgical specialist.

⁃ Cardiac function: no myocardial infarction within 1 year; no unstable angina; no symptomatic severe arrhythmia; no cardiac insufficiency.

• Women of childbearing potential must have a negative serum pregnancy test result within 7 days prior to the first dose of the test drug; men of childbearing potential or women of childbearing potential must use a highly effective contraceptive method (e.g., oral contraceptive pill, intrauterine device, abstinence from sexual intercourse, or barrier contraceptive method combined with spermicide) throughout the trial and continue to use contraception for 12 months after the end of treatment.