A Prospective, Randomized, Controlled Clinical Study on the Prevention of Chemotherapy Related Myelosuppression in Patients with Ewing's Sarcoma Using Trilaciclib

Inclusion Criteria

• •Age ≥ 14 years old and ≤ 40 years old;
• •Histologically confirmed Ewing's sarcoma;
• •Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) score of 0 to 1;
• •Have not received any anti-tumor treatment other than surgery in the past;
• •Expected survival of more than 3 months;
• •Possess sufficient organ and bone marrow function, with laboratory test values meeting the following requirements within 7 days prior to enrollment (no blood components, cell growth factors, albumin, or other corrective treatment drugs are allowed within 14 days prior to obtaining laboratory tests), as follows Blood routine: Absolute neutrophil count (ANC) ≥ 1.5 × 109/L, platelet count (PLT) ≥ 100 × 109/L, hemoglobin (HGB) ≥ 100 g/L (no transfusion or erythropoietin dependence within 14 days) Liver function: serum total bilirubin ≤ 1.25 times the upper limit of normal (ULN); ALT and AST ≤ 2.5 x ULN (≤ 5x ULN for patients with liver metastases); Serum albumin ≥ 30 g/L; Alkaline phosphatase (ALP) ≤ 5 × ULN.
• •Renal function: Serum creatinine (Cr) ≤ 1.25 × ULN, or creatinine clearance rate ≥ 60 mL/min (using the standard Cockcroft Gault formula): Urine routine results show urinary protein\<2+; For patients whose baseline urine routine test shows urinary protein ≥ 2+, 24-hour urine collection should be performed with a 24-hour urine protein quantification of\<1g.
• •Coagulation function: International normalized ratio (INR) or prothrombin time (PT) ≤ 1.5 times ULN; If the subject is receiving anticoagulant therapy, as long as the INR is within the intended range of use of the anticoagulant drug.
• •For female subjects of childbearing age, a urine or serum pregnancy test should be conducted 3 days before receiving the first study drug and the result should be negative;
• •The subjects and their sexual partners are required to use a medically approved contraceptive measure (such as intrauterine device, contraceptive pill, or condom) during the study treatment period and within 6 months after the end of the study treatment period.