This is a non-randomized Phase 2 portion of a study testing ALIMTA and epirubicin in combination for locally advanced or metastatic breast cancer. Epirubicin is a well-established drug for the therapy of breast cancer. Both ALIMTA and epirubicin have been combined with other drugs but they have not yet been combined with each other. It is expected that the patient will benefit from the different mechanisms of action of the two drugs.

Inclusion Criteria:

• Diagnosis of locally advanced or metastatic breast cancer not amenable to local treatment.
• Patients must be chemo-naive or have only neoadjuvant and/or adjuvant chemotherapy.
• Patients must have at least one measurable lesion in an area not previously irradiated.
• No chemotherapy at least 4 weeks prior to study enrollment.
• Signed informed consent from patient.

Exclusion Criteria:

• Treatment with any drug within the last 30 days that has not received regulatory approval.
• Serious systemic disorders, including active infection.
• Significant cardiovascular disease.
• Pregnancy or breast feeding.
• Inability or unwillingness to take folic acid or Vitamin B12 supplementation.