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/m² 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 × 10⁹/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.