Inclusion Criteria:

- Locally advanced or metastatic breast cancer not amenable to surgery or radiation
with curative intent

- Must have received any chemotherapy regimen in the past

- Evidence of tumor resistance to last chemotherapy defined as progression after 6
months of previous chemotherapy for advanced disease

- Must have measurable (by imaging techniques) disease

- Adequate bone marrow, liver and renal function

- Must provide evidence of informed consent and willingness and ability to comply with
scheduled visits, treatment plan and study procedures.

Exclusion Criteria:

- Received more than 2 prior chemotherapy regimens for metastatic disease

- Received in the past another drug of the same class as the investigational drug, i.e.
topoisomerase I inhibitor

- Enrolled in another clinical intervention study

- Pregnancy, breast feeding, fertile women refusing to use reliable contraceptive
methods

- Cardiac or thrombotic event in the last 12 months

- Brain metastases