GW572016 Combined With Trastuzumab For The Treatment Of Previously Trastuzumab-Treated Breast Cancer

Inclusion criteria: * Patients with confirmed breast cancer who have received prior trastuzumab. * Patients must have adequate blood, liver, and kidney function and either be fully active or restricted only in performing strenuous activity. * Female patients of child-bearing potential must be willing to abstain from intercourse from 2 weeks prior to administration of the first dose of study medication until 28 days after the final dose of study medication or be willing to consistently and correctly use an acceptable method of birth control. Exclusion criteria: * Patients with certain heart problems.