Romiplostim N01 for the Treatment of Thrombocytopenia Associated With Radiotherapy-Combined Treatment Regimens in Patients With Solid Tumors

Inclusion Criteria:

* Age ≥18 years, regardless of gender; Histopathologically confirmed solid tumor patients (including but not limited to nasopharyngeal carcinoma, lung cancer, breast cancer, etc.);
* Prior radiotherapy (RT) ≥45Gy (including standalone RT, concurrent/sequential chemoradiotherapy, or RT combined with other antitumor therapies, with treatment duration ≥2 weeks), regardless of prior induction/adjuvant chemotherapy;
* Platelet count \<75×10⁹/L within 3 days prior to enrollment, occurring during RT or within 1 month post-RT;
* Estimated survival ≥12 weeks at screening;
* ECOG score 0, 1, or 2;
* Premenopausal women/men of childbearing potential must agree to contraceptive measures during and for 6 months post-study; non-lactating patients;
* No participation in other drug clinical trials within 4 weeks prior to enrollment;
* Voluntary signing of informed consent after full comprehension of study requirements.

Exclusion Criteria:

* Patients with hematologic diseases, including lymphoma, leukemia, aplastic anemia, primary immune thrombocytopenia (ITP), myeloproliferative disorders, multiple myeloma, or myelodysplastic syndromes;
* Patients who experienced thrombocytopenia within 6 months prior to screening due to non-cancer treatments, including but not limited to EDTA-dependent pseudo-thrombocytopenia, hypersplenism, infection, or bleeding.
* Patients with brain tumors, brain metastases, bone marrow invasion, or bone marrow metastases;
* Patients with hemoglobin \<50 g/L after red blood cell transfusion or erythropoietin (EPO) treatment, or absolute neutrophil count \<1.0×10⁹/L after granulocyte colony-stimulating factor (G-CSF) treatment;
* Patients who experienced any arterial or venous thrombosis within 6 months prior to screening;
* Patients with severe cardiovascular diseases within 6 months prior to screening (e.g., NYHA Class III-IV heart failure), high-risk arrhythmias (e.g., atrial fibrillation), coronary stent placement, angioplasty, or coronary artery bypass grafting;
* Patients who received platelet transfusion within 5 days prior to enrollment;
* Patients who received thrombopoietin receptor agonist treatment within 4 weeks prior to study drug administration, recombinant human thrombopoietin (rhTPO) or rhIL-11 within 4 weeks prior to enrollment, or other platelet-enhancing traditional Chinese medicine within 1 week prior to enrollment;
* Patients with positive hepatitis C antibody and detectable HCV-RNA, positive hepatitis B surface antigen and detectable HBV-DNA, severe cirrhosis, HIV antibody positivity, or syphilis antibody positivity;
* Patients with ALT and AST ≥3×ULN (for subjects without liver metastasis) or ≥5×ULN (for subjects with liver metastasis) during screening;
* Patients with serum creatinine ≥1.5×ULN or estimated glomerular filtration rate (eGFR) ≤60 mL/min;
* Patients with known allergies or intolerances to the active ingredients or excipients of romiplostim N01 for injection;
* Patients who are pregnant, planning pregnancy, or breastfeeding;
* Patients deemed unsuitable for participation in the trial by the investigator.