First and Subsequent Cycle Use of Pegfilgrastim Prevents Febrile Neutropenia in Patients With Breast Cancer: A Multicenter, Double-Blind, Placebo-Controlled Phase III Study

Purpose We evaluated the efficacy of pegfilgrastim to reduce the incidence of febrile neutropenia associated with docetaxel in breast cancer patients. Patients and Methods Patients were randomly assigned to either placebo or pegfilgrastim 6 mg subcutaneously on day 2 of each 21-day chemotherapy cycle of 100 mg/m 2 docetaxel. The primary end point was the percentage of patients developing febrile neutropenia (defined as body temperature ≥ 38.2°C and neutrophil count < 0.5 × 10 9 /L on the same day of the fever or the day after). Secondary end points were incidence of hospitalizations associated with a diagnosis of febrile neutropenia, intravenous (IV) anti-infectives required for febrile neutropenia, and the ability to maintain planned chemotherapy dose on time. Patients with febrile neutropenia were converted to open-label pegfilgrastim in subsequent cycles. Results Nine hundred twenty-eight patients received placebo (n = 465) or pegfilgrastim (n = 463). Patients receiving pegfilgrastim, compared with patients receiving placebo, had a lower incidence of febrile neutropenia (1% v 17%, respectively; P < .001), febrile neutropenia–related hospitalization (1% v 14%, respectively; P < .001), and use of IV anti-infectives (2% v 10%, respectively; P < .001). The percentage of patients receiving the planned dose on time was similar between patients receiving pegfilgrastim and patients who initially received placebo (80% and 78%, respectively), as would be expected of the study design. Pegfilgrastim was generally well tolerated and safe, and the adverse events reported were typical of this patient population. Conclusion First and subsequent cycle use of pegfilgrastim with a moderately myelosuppressive chemotherapy regimen markedly reduced febrile neutropenia, febrile neutropenia–related hospitalizations, and IV anti-infective use.