To evaluate the overall survival of simmitinib versus investigator's choice of chemotherapy for Participants with advanced or metastatic oesophageal squamous cell carcinoma who have disease progression after first-line standard therapy.
Absolute Neutrophil count (ANC) ≥ 1.5 × 10^9/L;
Platelet count (PLT) ≥ 100× 10^9/L;
Hemoglobin (Hb) ≥ 90 g/L;
Serum creatinine ≤ 1.5 × ULN and Creatinine clearance (CCr)≥60mL/min(According to the Cockcroft-Gault formula);
1. Patients who have previously received any anti-tumor therapy within 4 weeks prior to randomization; 2. Patients who have previously received major surgical treatment、open biopsy、other clinical trial drug treatment or any live attenuated vaccine within 4 weeks prior to randomization, or are expected to received any live attenuated vaccine during the study.