Pegfilgrastim-gema Compared to Pegfilgrastim-roche for Prevention of Induced Neutropenia in Breast Cancer Patients.

Inclusion Criteria: * Female patients aged 18 to 70 years old. * Patients diagnosed having high risk stage 2 or stage 3 or 4 of breast cancer (by histopathological or cytological diagnosis) and need neoadjuvant, adjuvant chemotherapy, or with metastatic disease. * A priori has been decided to be treated with Peg-Filgrastim and subjects eligible for Peg-Filgrastim therapy according to indications and clinical use in the product monograph * Patients scheduled to receive 4 or 6 cycles of chemotherapy (Taxane combinations) with prophylactic Peg-Filgrastim at 3 weeks interval. Monoclonal Antibodies in addition to Taxane regimens are permitted. * Any acute adverse effects of prior therapy must have resolved to ≤ NCI CTCAE (Version 4.0) grade 1 (excluding alopecia) prior to Day 1 of Cycle 1 * Eastern Cooperative Oncology Group - ECOG Performance Status 0, 1 or 2 as determined on Day 1 or up to -3 of Cycle 1 prior to administration of chemotherapy * Patients must have adequate organ function including the following: 1. Adequate bone marrow functions, as determined within 3 days prior to administration of chemotherapy on Day 1 of Cycle 1 and as indicated by Hb ≥9,5 g/dl (transfusion permitted to be included in the trial ),WBC (white blood cell) ≥3,5 x 109/l, Absolute neutrophil count (ANC) ≥1.5 x 109/l, Platelets ≥95 x 109/l; 2. Adequate renal and hepatic function, as determined within 3 days prior to administration of chemotherapy on Day 1 of Cycle 1 and defined as follows, 1. Hepatic: Bilirubin ≤ 1.5 x the upper limit of normal (ULN) (unless elevation is known to be due to Gilbert's disease), Subjects must also meet one of the following criteria: 1. Alkaline phosphatase within normal reference range and both AST (aspartate aminotransferase) and ALT (alanine aminotransferase) \>2.5 x ULN; or 2. Alkaline phosphatase \<2.5 x ULN and both AST and ALT \<1.5 x ULN; or 3. Alkaline phosphatase \<5 x ULN and both AST and ALT within normal reference range; 2. Renal: Serum creatinine ≤ 1.5 mg/dl or creatinine clearance ≤ 60 ml/min (calculated according to the Cockcroft and Gault formula) * Patients of child-bearing potential must have a negative pregnancy test within 3 days prior to the first dose of chemotherapy and at day 1 or up to -3 days of each Cycle) and use at least one form of contraception as approved by the investigator during the study. * Life expectancy \>6 months Exclusion Criteria: Safety of treatment dependent criteria: * Presence of any serious concomitant systemic disorders incompatible with the administration of filgrastim, Peg-Filgrastim or any systemic disease that can influence the patient's safety according to doctor's diagnosis. * History of hypersensitivity to Peg-Filgrastim, filgrastim or E.coli derived proteins. * Serious local infection or active systemic infection within 10 days prior to enrollment or patients who have taken antibiotics within the previous 10 days * Pregnant or breast-feeding patients * Cardiac insufficiency, cardiomyopathy, significant cardiac dysrhythmia, unstable or advanced ischemic heart disease (NYHA III or IV) * Known bleeding disorder * Patient known to have HIV, Hepatitis B, Hepatitis C or who have a positive serology for HIV, Hepatitis B or Hepatitis C at screening * History or presence of sickle cell disease * Concurrent or prior radiotherapy within four weeks of randomization Criteria dependent on compliance with study procedures, or the evaluation of the response: * Unwilling to use a reliable and acceptable contraceptive method throughout the study period (fertile patients only) * Treatment with certain other agents to treat the malignant disease * Known drug addiction, including alcoholism * Treatment with any investigational product within 30 days prior to study drug administration * Concurrent prophylactic antibiotics * Previous participation in this study. * Already involved in another trial. * History of bone marrow or stem cell transplantation. * Previous therapy should not have included G-CSF (granulocyte-colony stimulating factor) Previous participation in this study: Subjects who are considered screening failures are allowed to be re-screened, except if have started chemotherapy. In case of re-screening the following assessments and evaluations do not have to be repeated: Demographics, Medical history, HIV, Hepatitis B and C serology.