A Prospective, Multicenter Study on the Efficacy and Safety of Romiplostim N01 for Chemotherapy-Induced Thrombocytopenia (CIT) in Children, Adolescents, and Young Adults (CAYA) With Hematological and Solid Tumors
The goal of this clinical trial is to evaluate the efficacy and safety of romiplostim N01 in treating chemotherapy-induced thrombocytopenia (CIT) in children and adolescents/young adults (CAYA; aged 6-24 years) with hematologic malignancies or solid tumors. The main questions it aims to answer are: * What proportion of participants achieve platelet count recovery (≥100×10⁹/L or an increase of ≥30×10⁹/L from baseline) within 3 weeks of romiplostim N01 treatment? * What is the safety profile of romiplostim N01 in this population, including the incidence and severity of adverse events (especially bleeding and thrombosis)? This is a single-arm study (no comparison group). Researchers will assess the outcomes against predefined efficacy thresholds and historical data (e.g., a 60.7% response rate reported for another TPO-RA, hetrombopag). Participants will: * Receive weekly subcutaneous injections of romiplostim N01 (starting dose: 2 µg/kg). * Have their romiplostim dose adjusted weekly based on platelet counts (increase by 1-2 µg/kg if platelets \<99×10⁹/L, maximum dose 10 µg/kg, stop when target recovery is met). * Undergo frequent monitoring, including blood tests (especially platelet counts), vital signs, physical exams, and assessment for adverse events and bleeding throughout the treatment and follow-up period.
• Voluntary participation with signed informed consent.
• Aged 6-24 years, any gender.
• ECOG performance status 0-2.
• Histologically/cytologically confirmed non-myeloid malignancy requiring high-intensity chemotherapy with ≥1 myelosuppressive agent.
• Patients with potential curative opportunity eligible for standard therapy.
• Chemotherapy-induced thrombocytopenia (platelets \<75×10⁹/L).
• Anticipated survival ≥8 months.
• Planned ≥2 additional chemotherapy cycles (21-/28-day cycles).
• Laboratory parameters meeting:
‣ Renal function: Cr ≤1.5×ULN; Ccr ≥55 mL/min.
⁃ Hepatic function:
• Total bilirubin ≤1.5×ULN; ALT/AST ≤3×ULN;
∙ For liver metastasis/cholangiocarcinoma: bilirubin ≤3×ULN, transaminases ≤5×ULN.
⁃ No participation in other drug trials within 4 weeks.
⁃ Good compliance with efficacy/safety follow-up per protocol.
⁃ Absence of severe complications (e.g., active GI bleeding/perforation, jaundice, obstruction, non-cancer fever \>38°C).
⁃ Ability to comprehend and sign informed consent.