Inclusion Criteria:

          -  Clinical stage I-III HER2 positive breast cancer treated with neoadjuvant chemotherapy
             including HER-2 directed treatment for at least 12 weeks.

          -  Residual invasive carcinoma in the breast or axillary nodes in the final pathology
             from resected tumor following neoadjuvant chemotherapy.

          -  Completed last cycle of cytotoxic chemotherapy or radiation > 30 days with resolution
             of all acute toxic effects of prior therapy to grade ≤ 2 (except alopecia)

          -  Currently on HER-2 targeted therapy (eg; trastuzumab +/- pertuzumab or adotrastuzumab
             emtansine (T-DM1) per standard of care) or has completed HER-2 targeted therapy less
             than 6 months ago

          -  Age ≥ 18 years.

          -  Eastern Cooperative Group (ECOG) performance status 0 or 1.

          -  Must have normal organ and marrow function as defined below within 30 days of start of
             treatment:

               -  Absolute neutrophil count (ANC) ≥ 1,500/ μL

               -  Platelets ≥ 75,000/ μL

               -  Total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN), except
                  patients with Gilbert's syndrome in whom total bilirubin must be <3.0 mg/dL

               -  AST/ALT ≤ 3 x institutional upper limit of normal (ULN)

               -  Creatinine ≤ 1.5 x institutional upper limit of normal (ULN)

               -  Hemoglobin A1C <6.5%

          -  Left ventricular ejection fraction (LVEF) above institutional lower limit of normal
             (by echocardiogram or MUGA scan within 90 days of registration).

          -  Females of child-bearing potential must agree to use dual methods of contraception and
             have a negative serum pregnancy test at screening, and males must use an effective
             barrier method of contraception if sexually active with a female of child-bearing
             potential. For both male and female participants, effective methods of contraception
             must be used throughout the study and for three months following the last dose.

          -  Ability to understand and willingness to sign a written informed consent document
             prior to initiation of any screening or study-specific procedures.

        Exclusion Criteria:

          -  Uncontrolled intercurrent illness including, but not limited to, ongoing or active
             infection, congenital prolonged QT syndrome, symptomatic congestive heart failure,
             unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations
             that would limit compliance with study requirements.

          -  Uncontrolled autoimmune disease requiring active systemic treatment.

          -  Known hypersensitivity reaction to the Granulocyte-macrophage colony stimulating
             factor (GM-CSF) adjuvant; any known contraindication to GM-CSF.

          -  Pregnant or breast feeding.

          -  Known HIV-positive.

          -  Known current or a history of hepatitis B or C virus, including chronic and dormant
             states, unless disease has been treated and confirmed cleared.

          -  Major surgery within 4 weeks of initiation of study drug.

          -  Current use of immunosuppressive agents or systemic corticosteroids. Topical, ocular,
             intra-articular, intranasal, inhalational corticosteroids (with minimal systemic
             absorption) are allowed. Patients who have received systemic corticosteroids ≤ 30days
             prior to starting study drug will be excluded.

          -  Potential participant is currently enrolled in any other clinical protocol or
             investigational trial that involves administration of experimental therapy and/or
             therapeutic devices, or investigational drug.