Inclusion Criteria:

- Patients with HER2+ stage IV breast cancer that have been maximally treated and not
in a complete remission

- Patients must have measurable disease per imaging studies performed within 60 days of
enrollment as described below:

- Extra skeletal disease that can be measured with conventional or spiral computed
tomography (CT) techniques

- Skeletal or bone-only disease that is measurable by fludeoxyglucose F 18 (FDG)
positron emission tomography (PET) or magnetic resonance imaging (MRI)

- Patients can be receiving trastuzumab and/or lapatinib and/or hormonal therapy and/or
bisphosphonate therapy

- HER2 overexpression in the primary tumor or metastasis by immunohistochemistry (IHC)
of 3+, or documented gene amplification by fluorescent in situ hybridization (FISH)
analysis

- Patients must be human leukocyte antigen (HLA)-A2 positive

- Eastern Cooperative Oncology Group (ECOG)/Zubrod scale of =< 1

- Patients must be off immunosuppressive treatments (i.e., chemotherapy or systemic
steroids) 3 weeks prior to first vaccine

- Patients on trastuzumab must have a baseline left ventricular ejection fraction
(LVEF) measured by multi gated acquisition scan (MUGA) or echocardiogram (ECHO) >=
the lower limit of normal for the facility within 3 months of enrollment to study

- Subjects of reproductive ability must agree to use contraceptives during the entire
study period

Exclusion Criteria:

- White blood cell (WBC) < 3000/mm^3

- Hemoglobin (Hgb) < 10 mg/dl

- Platelets < 100,000/mm^3

- Serum creatinine > 2.0 mg/dl

- Serum bilirubin > 1.5 x upper limit of normal

- Any contraindication to receiving sargramostim (GM-CSF) based vaccine products

- Concurrent enrollment in other treatment studies

- New York Heart Association functional class III-IV heart failure, symptomatic
pericardial effusion, or unstable angina

- Pregnant or breast-feeding women

- History of disorders associated with immunosuppression such as human immunodeficiency
virus (HIV)

- Active brain metastasis