<qa>  What is the primary objective of this study?CI-1033 is an experimental drug that acts as an inhibitor of erbB EGFR receptors, which may be involved in tumor growth. The primary objective of this study is to assess the antitumor activity of CI-1033 in patients with metastatic breast cancer. Patients with histologically confirmed metastatic Stage IV breast cancer and who have received no more than 2 prior cytotoxic chemotherapy regimens are eligible for this study. CI-1033 is administered orally. Patients are required to have blood tests periodically while receiving treatment and will be closely monitored throughout the study for possible side effects and response to treatment. Patients may not have received any prior treatment with other agents that target erbB receptors, including Herceptin trastuzumab or Iressa gefitinib. 