Inclusion Criteria:

- Has MBC that is measurable by RECIST or has nonmeasurable disease with serum CA27.29
(or CA15.3) ≥ 50

- Has Human Epidermal Growth Factor Receptor 2 (HER2) negative breast cancer

- Prior chemotherapy is permitted with no limit on the number of prior regimens

- Two weeks or more have elapsed since last chemotherapy or radiation treatment

- Has an Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of 0-2

- Is female, ≥ 18 yrs of age

- Protocol defined appropriate laboratory values

- Negative pregnancy test within 7 calendar days prior to registration

- Has signed a patient informed consent

Exclusion Criteria:

- Had prior treatment with ixabepilone or other epothilones

- Has HER2+ disease

- Has a known, prior, severe (National Cancer Institute Common Terminology Criteria
Adverse Events [NCI CTCAE] Grade 3-4) history of hypersensitivity reaction to a drug
formulated in Cremophor ® EL (polyoxyethylated castor oil)

- Is receiving concurrent immunotherapy, hormonal therapy or radiation therapy

- Is receiving concurrent investigational therapy or has received such therapy within
the past 30 days

- Has peripheral neuropathy > Grade 1

- Has evidence of central nervous system (CNS) involvement requiring radiation or
steroid treatment. Participants with stable brain metastases who are off steroids at
least 2 weeks are eligible

- Is pregnant or breast feeding