This study will evaluate the safety and feasibility of administering a peptide vaccine consisting of twelve different tumor-rejection antigens to patients with high risk (TxN2-3M0) or metastatic breast cancer with no evidence of disease following their completion of systemic therapy. The vaccine is designed to elicit immune responses against twelve different pathways that are essential to tumor growth, survival and metastasis.

The primary endpoint will be to determine the safety and feasibility of administering cancer peptides to patients with high risk (TxN2-3M0) or metastatic breast cancer with no evidence of disease following their completion of systemic therapy, with the secondary objectives of evaluating immune response disease relapse survival. Two cohorts of 9 patients each will be treated with different doses of the vaccine. They will receive the peptide vaccine subcutaneously on weeks 0,1,2,4,5, and 6 and then receive the immunizations every 1 month for 6 months or disease recurrence. Toxicity will be assessed at each dose level using CTCv3 toxicity criteria.

Inclusion Criteria:

• HLA-A2 patients with histologically confirmed, TxN2-3M0 or metastatic breast cancer with no evidence of disease who have completed their adjuvant systemic chemotherapy or trastuzumab
• Subjects will not be treated until 4 or more weeks after any prior chemotherapy, radiation therapy or immunotherapy, but they may be receiving hormonal therapy

Exclusion Criteria:

• History of autoimmune disease
• Serious intercurrent chronic or acute illness
• Active hepatitis
• Serologic evidence for HIV, splenectomy
• Receiving steroid or immunosuppressive therapy