Inclusion Criteria:
* Willing to sign the informed consent form and be able to comply with the requirements of the protocol;
* Age≥ 18 years old, ≤ 75 years old;
* Patients with solid tumors confirmed by histopathology or cytology;
* Cohort 1 requires that the patient has not used G-CSF drugs during this chemotherapy treatment;
* Cohort 2 requires patients to suffer ≥3 grade ANC reduction after the first course of chemotherapy, and there still has the risk in the subsequent chemotherapy;
* Patients planned to receive at least 2 courses of chemotherapy regimens with FN high risk or Intermediate risk with other risk factors (including, but not limited to,≥65 years-old, poor nutritional/performance status i.e., ECOG score ≥2, etc.);
* ECOG score 0-2;
* Expected survival of not less than 12 weeks;
* Neutrophil count (ANC) ≥ 2.0×109/L, hemoglobin (Hb) ≥90g/L and platelet (PLT) ≥80 × 109/L before enrollment;
* Liver and kidney function meet the following criteria: total bilirubin ≤ 1.5 times the upper limit of normal, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 2.5 times the upper limit of normal, serum creatinine ≤ 1.5 times the upper limit of normal;
* Left Ventricular Ejection Fractions≥50%;
* Women of non-childbearing potential, i.e. women who have been postmenopausal for at least 1 year or have undergone sterilization surgery (bilateral tubal ligation, double oophorectomy or hysterectomy); Patients of childbearing potential agree to use adequate contraception within 1 month prior to the start of the trial and 30 days after the end of the study: condoms, spermicidal condoms, foams, gels, diaphragms, intrauterine devices (IUDs), contraceptives (administered orally or by injection).
* The investigator judges that the patient can tolerate treatment with Efbemalenograstim alfa.
Exclusion Criteria:
* Uncontrolled infection within 72 hours prior to chemotherapy or receiving systemic antibiotic therapy;
* Pregnant or lactating women;
* Have received bone marrow transplantation or stem cell transplantation in the past;
* Have 2 or more kinds of primary malignant tumors at the same time; However, the following exceptions are: 1) malignant tumors that have complete response for at least 2 years prior to enrollment and do not require other treatment during the study period; 2) non-melanoma skin cancer or lentigo maligna that has been adequately treated and has no evidence of disease recurrence; 3) carcinoma in situ that has been adequately treated and has no evidence of disease recurrence;
* Psychiatric or brain metastases;
* Surgical procedure and/or presence of trauma within 4 weeks;
* Clinical, electrocardiogram or other means of diagnosis of acute congestive heart failure, cardiomyopathy or myocardial infarction;
* Concomitant diseases that may lead to splenomegaly;
* Subjects with diagnosis of acute infection, chronic active hepatitis B within 1 year (unless known to be negative for hepatitis B virus antigen prior to enrollment), or hepatitis C;
* Known human immunodeficiency virus (HIV) seropositive, or AIDS;
* Active tuberculosis disease; or recent exposure to a person with tuberculosis, unless the tuberculin test is negative; or tuberculosis patients receiving treatment; or chest x-ray for suspected cases of tuberculosis;
* Patients with sickle cell anemia;
* Known hypersensitivity to granulocyte colony-stimulating factors or excipients of drugs;
* Use of other research drugs of the same type within 1 month before being selected for this study;
* In the opinion of the investigator, the patient has diseases or symptoms that are not suitable for participation in this study, and the study drug may harm the patient's health or affect the judgment of adverse events.
