Efficacy and Safety of Hetrombopag in Preventing Chemotherapy-induced Thrombocytopenia in Gastrointestinal Tumors

Inclusion Criteria:

1. age ≥18 years;
2. pathologically confirmed gastrointestinal tumors (including esophageal cancer, gastric cancer, colorectal cancer, etc.);
3. during the previous chemotherapy cycle (N-1 cycle), patients had a minimum platelet count of ≥75×10⁹/L and at least one high-risk bleeding factor (① history of bleeding; ② previous treatment with platinum agents, gemcitabine, cytarabine, anthracyclines, etc.; ③ tumor cell bone marrow infiltration; ④ previous or ongoing radiotherapy, especially to long bones or flat bones such as the pelvis or sternum);
4. during the current chemotherapy cycle (N cycle), patients have a platelet count of ≥100±25×10⁹/L;
5. undergoing treatment cycles of 14 or 21 days and requiring at least one more cycle of therapy.
6. ECOG score: 0-2 points;
7. Adequate hematopoietic, liver, and kidney function:

   * Neutrophil count ≥ 1.5 x 10⁹/L
   * Hemoglobin ≥ 9.0 g/dL
   * Creatinine clearance ≥ 40 mL/min (Cockcroft-Gault formula)
   * For patients without liver metastasis, AST and ALT ≤ 2.5 times the upper limit of normal;
   * Bilirubin ≤ 2 times the upper limit of normal;
   * APTT and PT ≤ 1.5 times the upper limit of normal
8. Signed informed consent form.

Exclusion Criteria

1. Previous use of TPO-RA drugs;
2. Pre-treatment conditions that cause thrombocytopenia, such as hypersplenism or immune thrombocytopenia;
3. History of thrombosis;
4. Hematologic diseases (anemia, leukemia, autoimmune hemolytic diseases, etc.);
5. Major cardiovascular diseases (acute myocardial infarction, cerebral thrombosis, cerebral hemorrhage, etc.);
6. Pregnant or breastfeeding women;
7. Participation in other drug clinical trials within 4 weeks;
8. Poor compliance, unable to cooperate or report treatment responses;
9. Need for other antiplatelet or platelet-enhancing drugs, including traditional Chinese medicine and herbal preparations;
10. Use of prior platelet-stimulating drugs within 5 half-lives before first dose;
11. Platelet transfusion within 3 days before first dose.