e17572 Background: Balugrastim is a recombinant fusion protein composed of human serum albumin and human granulocyte colony-stimulating factor, which allows for once-per-chemotherapy cycle administration. We present a combined analysis of two double-blind, randomized Phase III studies comparing efficacy and safety of balugrastim vs pegfilgrastim in breast cancer patients receiving myelosuppressive chemotherapy (CTx). Methods: All patients were treated with doxorubicin 60 mg/m2 followed by docetaxel 75 mg/m2 administered by i.v. infusion on Day 1 of a 21-day cycle for up to 4 cycles. For each cycle, patients received a single s.c. injection of balugrastim approximately 24 hours after administration of CTx. The primary endpoint for both studies was duration of severe neutropenia (DSN) in Cycle 1. Safety of balugrastim was assessed by evaluating the type, frequency, and severity of adverse events (AEs); changes in laboratory parameters and vital signs, and immunogenicity over time. Analyses were performed in the per-protocol population. Results: A total of 469 patients were randomized to receive balugrastim 40 mg (N=235) or pegfilgrastim 6 mg (N=234). Mean DSN in Cycle 1 was 1.1±1.11 days in patients receiving balugrastim (n=236) and 1.0±1.14 days in patients receiving pegfilgrastim (n=234). Non-inferiority was demonstrated by statistical analysis for balugrastim vs pegfilgrastim for reduction in DSN across studies. Patients treated with balugrastim had a significantly shorter time to ANC recovery in Cycle 1 vs pegfilgrastim (2.0 vs 2.3 days; P=0.015). No other significant differences were seen between treatment groups in either study for any other secondary endpoints in Cycles 1–4. The safety profile was similar for both drugs, with the incidence of AEs consistent with the underlying medical condition and administration of myelosuppressive CTx. Conclusions: In both Phase III studies, non-inferiority was clearly demonstrated for balugrastim 40 mg vs pegfilgrastim 6 mg. Balugrastim is a safe and effective alternative to long-acting pegfilgrastim for reducing DSN in breast cancer patients receiving myelosuppressive chemotherapy. Clinical trial information: 2010-019001-42.
Ixabepilone plus capecitabine in metastatic breast cancer patients with reduced performance status previously treated with anthracyclines and taxanes: a pooled analysis by performance status of efficacy and safety data from 2 phase III studies
