FH-006 Versus Investigator's Choice of Chemotherapy in Patients With Locally Advanced, Recurrent, or Metastatic Esophageal Squamous Cell Carcinoma Who Have Failed Prior PD-1/PD-L1 Inhibitor Combined With Platinum-Based Chemotherapy.

Inclusion Criteria: 1. Age 18 to 75 years old (including boundary values) 2. Volunteer to participate in this clinical study and sign informed consent; 3. ECOG score 0-1; 4. Expected survival ≥3 months; 5. Patients diagnosed with esophageal squamous cell carcinoma by histological or cytological examination; 6. Previously, only PD-1/PD-L1 Inhibitor Combined With Platinum-Based Chemotherapy were received; 7. There is at least one measurable lesion that meets the RECIST 1.1 criteria; 8. Adequate bone marrow and organ function. Exclusion Criteria: 1. Received anti-tumor therapies such as chemotherapy, radiotherapy, biological therapy, targeted therapy, or immunotherapy within 4 weeks before the first dose of the study 2. Toxicities caused by previous anticancer therapy were not recovered to CTCAE 6.0 Grade≤1; 3. Individuals with Leptomeningeal metastasis or Active brain metastases; 4. Individuals with a history of GI perforation or fistula, unstable GI bleeding; 5. Individuals with a history of severe cardiovascular and cerebrovascular diseases; 6. The researcher determined that there are other situations that are not suitable for participation.