Safety Study in Subjects With Metastatic Breast Cancer Who Progressed After Taxanes Treatment.

In areas where trastuzumab is available with no barriers to access, all patients must have received trastuzumab in the adjuvant or metastatic setting . However, in countries where trastuzumab is not approved or is not available to patients due to reimbursement or other considerations, trastuzumab naïve patients are allowed considering the efficacy data of Lapatinib in this subset of patients. This trial uses a design to ensure a selection of one or more of the better treatment combination for additional clinical Approximately (165), who meet the criteria for efficacy analysis as defined, will be enrolled in the study in a single stage process. The sample size will be accrued in 16 months, with further follow-up for a 24 months study period from randomization or until progression. The study includes a Screening/Baseline Period, a Treatment Period and a post-treatment Follow-Up Period. Patients will continue to receive investigational products until disease progression or early discontinuation from investigational product for other reasons. Patients who discontinue investigational product(s) without disease progression will continue to be evaluated for efficacy until progression or until receiving the first subsequent anti-cancer therapy. Once progression is documented, all patients will be followed for survival at approximately 3-month intervals until death.