NOTE: This study is no longer accepting patients.

Our study plans to look at the effectiveness of an investigational therapy in patients with metastatic breast cancer.

This is a phase II research study investigating the effectiveness and safety of ZK-Epothilone (ZK-Epo), an experimental therapy in women with breast cancer that has spread to other parts of their bodies. ZK-Epo is an Epothilone, a new class of chemotherapy, that has demonstrated activity against breast cancer and other tumor types in pre-clinical studies.

To date, ZK-Epo has been given to more than 200 cancer patients. These patients have been enrolled in studies of solid tumor cancers such as breast cancer, ovarian cancer, and head and neck cancers.

Participants in this study must have active disease and have received at least one previous regimen of chemotherapy.

Eligible participants will have previously received both an anthracycline and a taxane in the past to treat their breast cancer.