The goal of this real-world study is to compare the efficacy and safety of QL0605 administered 24 hours and 48 hours after chemotherapy in breast cancer patients.

Patients with stage invasive breast cancer who were scheduled to receive at least 2 cycles of adjuvant or neoadjuvant chemotherapy with TAC/TC/TCbH regimen were eligible for this multicenter, open-label, randomized trial. Patients were randomized (2:1) to receive QL0605 24 hours (24h group) or 48 hours (48h group) after the end of each cycle of chemotherapy. The primary endpoint was the incidence rate of FN for cycle 1. The secondary endpoints included the incidence rates of grade 3/4 neutropenia, chemotherapy dose reduction and chemotherapy delay due to neutropenia, antibiotic administration, the pain (bone, muscle, or joint), ect.

Inclusion Criteria:

• Aged≥18 years；
• The expected survival period is more than 3 months;
• ECOG≤ 2;
• Invasive breast cancer diagnosed by histopathology;
• Plan to receive TAC, TC or TCbH chemotherapy;
• Subjects with good hematology, liver, lung and kidney function ;
• Signed informed consent.

Exclusion Criteria:

• Known hypersensitivity to rhG-CSF or PEG-rhG-CSF;
• Female patients during pregnancy or lactation;
• The previous malignant tumors were not cured;
• Received chemotherapy or radiotherapy within 4 weeks before screening;
• Received PEG-rhG-CSF within 6 weeks before screening;
• Suffering from uncontrollable infectious diseases within 2 weeks before screening.