 Inclusion Criteria: - Breast cancer, previously untreated Exclusion Criteria: - Active infection requiring treatment with systemic intravenous or oral anti-infectives antibiotic, antifungal, antiviral within 72 hours of chemotherapy - Prior malignancy within the last 5 years, with the exception of surgically cured basalsquamous skin cell carcinoma, ductal carcinoma in situ of the breast andor carcinoma of the cervix in situ - History of impaired cardiac status e.g., severe heart disease, cardiomyopathy or congestive heart failure - Major surgery within 2 weeks prior to randomization - Previous exposure to cytokines within two weeks prior - Concurrent use of other investigational agents 