Study Evaluating PEG-G-CSF Injectionin Preventing Neutropenia After Chemotherapy

Inclusion Criteria:

1. Age ≥18 years, ≤75 years

2. Female breast cancer patients with a pathohistologically confirmed diagnosisrequiring first-time adjuvant or neoadjuvant chemotherapy and for whom the followingregimens are appropriate: ① EC regimen (epirubicin 90 mg/m2 iv day 1,cyclophosphamide 600 mg/m2 iv day 1) ② TC regimen (cyclophosphamide 600 mg/m2 iv day 1, docetaxel 75 mg/m2 iv day 1) ③ TCb regimen ( docetaxel 75 mg/m2 iv day 1,carboplatin AUC=5 iv day 1); Note: TCb regimens such as the combination of anti-HER2targeting drugs H (trastuzumab) and P (pertuzumab) can also be included.

3. Physical condition ECOG score ≤ 1;

4. Weight ≥ 45kg;

5. Peripheral blood cell counts eligible for chemotherapy: white blood cell (WBC) count ≥ 3.5 x 109/L, neutrophil count (ANC) ≥ 1.5 x 109/L, hemoglobin (HB) ≥ 90 g/L,platelet (PLT) count ≥ 100 x 109/L, normal coagulation or abnormalities of noclinical significance, and no tendency to bleed;

6. Survival is expected to be 6 months or more;

7. The subject is willing to use an appropriate method of contraception for theduration of the trial;

8. Subjects agreed to follow the trial treatment protocol and visit schedule, enrolledvoluntarily, and signed a written informed consent form.

Exclusion Criteria:

1. The subjects who have received radiation therapy within 4 weeks prior torandomization;

2. Those who have received hematopoietic stem cell transplantation or bone marrowtransplantation

3. Patients who have been treated with G-CSF analogs or PEG-G-CSF analogs within 4weeks prior to randomization;

4. Subjects with a history of chronic granulocytic leukemia or myelodysplasticsyndromes;

5. People at high risk for ARDS;

6. Patients with unexplained splenomegaly on physical examination and/or CT scan orultrasound, as well as any condition that may cause splenomegaly (e.g., thalassemia,glandular fever, malaria, etc.);

7. Patients who currently have or have had sickle cell anemia;

8. Those with a combined history of malignant tumors (except for the following: curednon-melanoma skin cancer, cervical cancer in situ, limited prostate cancer,superficial bladder cancer, and other malignant tumors with a disease-free survivalperiod of more than 5 years);

9. Those diagnosed with advanced breast cancer combined with distant metastases;

10. Patients with known cerebrovascular malformations (e.g., cerebral hemangiomas),epilepsy;

11. Patients with severe mental or neurological disorders;

12. Patients with severe cardiovascular disease: history of myocardial infarction within 1 year prior to first administration of study drug; sick sinus syndrome,atrioventricular block II or greater, ventricular fibrillation, torsionalventricular tachycardia, sustained ventricular tachycardia; electrocardiogramindicative of abnormal clinically significant QRS wave lowering; congenitalprolonged history of the QT interval; left ventricular ejection fraction <50%; NYHAcardiac function class III or IV; poorly controlled hypertension. Poorly controlledhypertension: blood pressure >160 mmHg systolic and/or >100 mmHg diastolic despiteantihypertensive medications; congestive heart failure; stable coronary arterydisease; unstable angina pectoris;

13. Liver function indexes: ALT, AST, TBIL ≥1.5 times the upper limit of normal beforeenrollment; Kidney function indexes: Scr ≥1.5 times the upper limit of normal;

14. Positive for Hepatitis B surface antigen (HBsAg) or Hepatitis B core antibody (HBcAb) and peripheral blood Hepatitis B Virus (HBV) DNA test is greater than thenormal range; Positive for Hepatitis C Virus (HCV); Positive for HumanImmunodeficiency Virus (HIV);

15. Those with a current active infection (and a temperature ≥38°C) or who have receivedsystemic anti-infective therapy within 72 hours prior to chemotherapy;

16. Patients with severe mouth ulcers;

17. Participated in 3 or more clinical trials of a drug within the last year, orparticipated in any clinical trial of a drug within the last 3 months, as a subjectand actually used the test drug;

18. Hypersensitivity to the adjuvant or neoadjuvant chemotherapeutic agents used (e.g.,docetaxel, epirubicin, carboplatin, cyclophosphamide) and to PEG-G-CSF and G-CSFanalogs;

19. Lithium-treated patients were required during the clinical trial;

20. Alcohol-dependent individuals or those with a history of substance abuse;

21. Lactating and pregnant females and those planning a pregnancy within 6 months of thelast injection of the test drug in this study;

22. Combined primary diseases of the cerebrovascular, hepatic, renal, endocrine, andhematologic systems of a severity judged by the investigator to be inappropriate forparticipation in this clinical trial;

23. Other patients who, in the judgment of the investigator, are not suitable subjectsfor this trial.