Inclusion Criteria:

- Stage IIIB or Stage IIIC breast cancer who are within 1 year of diagnosis and
initiating treatment with chemotherapy and trastuzumab; and are in complete remission

- Stage IV breast cancer in first complete remission and defined as NED (no evidence of
disease) or with stable bone only disease who are within 6 months of initiating
maintenance trastuzumab

- NED status should be documented by chest/abdominal CT, PET or PET/CT within the last
90 days

- Bone only disease documented as stable or healed by PET, PET/CT, or MRI within the
last 90 days; stable bone-only disease must be documented with bone scan performed
within the last 6 months

- HER2 overexpression by IHC of 2+ or 3+, in the primary tumor or metastasis or
documented gene amplification by FISH analysis; if overexpression is 2+ by IHC, then
patients must have HER2 gene amplification documented by FISH

- Eligible subjects must have been treated to NED or stable bone only disease status
with trastuzumab and/or chemotherapy and be off cytotoxic chemotherapy or
immunosuppressive agents (e.g. systemic steroids) for at least 30 days prior to
enrollment (concurrent hormonal therapy allowed; concurrent bisphosphonate therapy
allowed)

- Patients on trastuzumab should continue trastuzumab monotherapy per standard of care
(the dosing and schedule of trastuzumab should follow standard guidelines as
described below: trastuzumab 2mg/kg IV weekly or trastuzumab 6mg/kg IV every 3
weeks)

- Subjects must have an ECOG Performance Status Score =< 1

- Non-menopausal female subjects must agree to contraception for the remainder of their
childbearing years

- Male subjects must use an acceptable form of contraception throughout the course of
the study

- Hematocrit >= 30,000

- Platelet count >= 100,000

- WBC >= 3000/mcl

- Stable creatinine =< 2.0 mg/dl or a creatinine clearance greater than 60 ml/min

- Serum bilirubin < 1.5 mg/dl

- SGOT < 2x ULN

- Laboratory tests should be performed within 60 days of enrollment

- Subjects must have recovered from major infections and/or surgical procedures and, in
the opinion of the investigator, not have any significant active concurrent medical
illnesses precluding protocol treatment

- Patients on trastuzumab monotherapy must have adequate cardiac function as
demonstrated by normal ejection fraction (EF) on MUGA scan or echocardiogram
performed within last 6 months

Exclusion Criteria:

- Subjects cannot be simultaneously enrolled in other treatment studies

- Patients cannot be receiving any other concurrent immunomodulators besides
trastuzumab

- Any contraindication to receiving GM-CSF based vaccine products

- Cardiac disease, specifically restrictive cardiomyopathy, unstable angina within the
last 6 months prior to enrollment, New York Heart Association functional class III-IV
heart failure on active treatment with normalized LVEF on therapy, and symptomatic
pericardial effusion

- Active autoimmune disease

- Subjects can not have active immunodeficiency disorder, e.g. HIV

- Cannot be pregnant or breast feeding