Utidelone and Anlotinib in Advanced Recurrent Metastatic Esophageal Cancer

Inclusion Criteria:

1. Histological and/or cytology confirmed advanced or unresectable recurrent esophageal carcinoma
2. All patients had failed first-line chemotherapy (disease progression or unacceptable toxicity occurs).

   Patients may also be included if they receive standard neoadjuvant/adjuvant chemotherapy and relapse within 6 months of completion.
3. All patients were not accepted any treatment(chemotherapy, radiotherapy, surgery, etc.) within 4 weeks before enrollment.
4. The subject has at least one evaluable lesion (measurable or non-measurable) by the RECIST 1.1.
5. Male or female, ≥ 18 years of age, ≤ 75 years of age.
6. ECOG performance status 0-1.
7. Patients with a life expectancy of more than 3 months.
8. Baseline routine blood tests within 1 week prior to enrollment is normal. No rhG-CSF use and no blood transfusion/EPO etc. within 14 days prior to enrollment.

   * Neutrophil count (ANC) ≥ 1.5 × 109/L.
   * Hemoglobin ≥9.0 g/dL.
   * platelet count (PLT) ≥ 80 × 109/L
9. Blood biochemistry test result is normal within 1 week prior to enrollment (based on normal values at each site's laboratory).

   * Total bilirubin (TBIL) ≤ 1.5× the upper limit of normal value (ULN)
   * Serum Glutamic Pyruvic Transaminase/Alanine Amino transferase (SGPT /ALT) ≤ 3× ULN (in the case of liver metastases ≤ 5 × ULN)
   * Serum Glutamic-oxaloacetic Transaminase/Aspartate Aminotransferase (SGOT /AST) ≤ 3× ULN (in the case of liver metastases ≤ 5 × ULN)
   * Creatinine clearance (Ccr) ≥50 ml/min.
10. Fertile males and females of childbearing potential must agree to use effective contraception during the study and within 90 days after the last dose. The blood or urine pregnancy test for female patients of childbearing age prior to enrollment must be negative.
11. Patients must sign the informed consent form and commit to complying with the requirements of this study.

Exclusion Criteria:

1. Patients who have received antitumor therapy, including chemotherapy, radiotherapy, biologic therapy, targeted therapy, immunotherapy, or antitumor herbal therapy, within 4 weeks. With the exception of the following:

   * Nitrosoureas or mitomycin C within 6 weeks prior to the first use of the study drug;
   * Oral fluorouracil and small molecule targeted drugs for 2 weeks prior to the first use of the study drug or within the drug's 5 half-life (whichever is longer);
   * Chinese medicines with antitumor indications within 2 weeks before the first use of the study drug.
2. Major organ surgery (excluding puncture biopsy) within 4 weeks prior to the first dose of study drug had major organ surgery (excluding puncture biopsy) or significant trauma within 4 weeks prior to the first dose of study drug, or required elective surgery during the trial.
3. Patients with symptomatic peripheral neuropathy with CTCAE 5.0 grade ≥2
4. Previous grade 3 or higher neurological related adverse reactions with anti-microtubule drugs.
5. Severe allergy to castor oil, or serious adverse effects from previous use of anti-microtubule drugs Those with severe allergy to castor oil or those who have experienced serious adverse reactions to previous anti-microtubule drugs.
6. Patients who are pregnant (positive result from the pregnancy test) or lactating.
7. Patients whose prior adverse reactions to anti-tumor therapy have not recovered to CTCAE 5.0 grade ≤1 (except for toxicity such as alopecia which poses no safety risk in the judgment of the investigator).
8. Patients with symptomatic CNS metastases or meningeal metastases, or uncontrollable metastases.
9. Patients with an active infection that currently requires systemic anti-infective therapy, including but not limited to: HIV, active hepatitis B/C infection.
10. Patients with history of severe cardiovascular disease
11. Patients with mental disorders or poor compliance.
12. Subjects who, in the opinion of the investigator, have a history of other serious systemic diseases, or other reasons that make participation in this trial inadvisable.