A Safety and Immunology Study of a Modified Vaccinia Vaccine for HER-2(+) Breast Cancer After Adjuvant Therapy

Inclusion Criteria:

   - Signed Informed Consent

   - Women, ≥ 18 years of age

   - Histologically documented, HER-2-positive breast cancer without metastatic disease.
   Hormone receptor (ER/PR) status may be either positive or negative. HER-2 (+) status
   may be determined by one of the following measurements:

   - Immunohistochemistry 3+ or FISH/CISH+ (HER-2 gene signal to centromere 17 signal > 2).
   NOTE: HER-2 assessment may have been on initial diagnosis and need not be repeated.

   - Patients should be assessed as having no evidence of disease (NED) at the end of
   adjuvant chemotherapy. In addition, these patients must have a clinical evaluation and
   lab work as standard of care disease assessment without evidence of recurrence within
   28 days of the first planned dose of MVA-BN®-HER2.

   - Completed adjuvant and/or neoadjuvant chemotherapy for breast cancer at least 3 months
   previously (measured from the date of the last dose of chemotherapy) and prior to the
   first planned dose of MVA-BN®-HER2).

   - ECOG Performance Score of 0, 1.

   - Predicted life expectancy ≥ 12 months

   - Left ventricular ejection fraction (LVEF) by ECHO ≥ LLN as defined by institutional
   standards

   - Women of childbearing potential must:

      - have a negative serum or urine pregnancy test, and

      - must agree to use a medically acceptable barrier and/or chemical method of
      contraception throughout the study treatment period and for 28 days after the
      last dose of MVA-BN®-HER2.

   - No significant cardiac, bone marrow dysfunction, or coagulopathy (defined as no Grade
   3 or greater AE according to NCI CTCAE v 3.0). No significant hepatic or renal
   dysfunction (defined as no Grade 2 or greater AE according to NCI CTCAE v 3.0.
   Patients with a known history of a CLINICALLY NON-SIGNIFICANT laboratory parameter may
   be eligible for inclusion provided an exemption is granted by the study Medical
   Monitor prior to enrollment.

   - A negative virology screen for HIV, HBsAg, and HCV

Exclusion Criteria:

   - Congestive heart failure (NYHA Class III or IV), unstable angina, or cardiovascular
   disease such as stroke or myocardial infarction (current or within the past 6 months)

   - History of cardiac toxicity secondary to chemotherapy or Herceptin immunotherapy (LVEF
   decline of 15% or greater from baseline)

   - History of prior malignancies other than breast cancer within the past 5 years,
   excluding basal or squamous cell carcinoma of the skin or carcinoma in situ of the
   cervix

   - Any breast cancer metastases beyond the lymph nodes

   - Known allergy to eggs, egg products, or aminoglycoside antibiotics, e.g., gentamicin
   or tobramycin

   - Chronic administration (defined as 6 or more consecutive days of use) of systemic
   corticosteroids within 14 days of the first planned dose of MVA-BN®-HER2. Limited use
   of inhaled steroids, nasal sprays, eye drops, and topical creams for small body areas
   is allowed.

   - History of or active autoimmune disease. Persons with vitiligo or thyroid disease
   taking thyroid replacement hormones are not excluded.

   - Prior solid organ or hematopoietic allogenic transplant(s)

   - Prior use of hematopoietic growth factors (e.g., GM-CSF) within 14 days of the first
   planned dose of MVA-BN®-HER2

   - Receipt of an investigational agent within 28 days of the first planned dose of
   MVA-BN®-HER2

   - Prior "vaccine" therapy for breast cancer at any time

   - Vaccination:

Live (attenuated) vaccine (e.g., FluMist®) Vaccination with a live vaccine within 28 days
of the first planned dose of MVA-BN®-HER2, or plans to receive a live vaccine within 28
days after the last dose of MVA-BN®-HER2 is not allowed Killed (inactivated) vaccine
(e.g.,PneumoVax®) Vaccination with a killed vaccine within 14 days of the first planned
dose of MVA-BN®-HER2, or plans to receive a killed vaccine within 14 ' days after the last
dose of MVA-BN®-HER2 is not allowed

   - A maximum cumulative dose of prior doxorubicin > 360 mg/m2 or epirubicn > 720 mg/m2

   - Radiation therapy within 14 days of the first planned dose of MVA-BN®-HER2 or plans
   for radiation therapy after enrollment. Prior to initiating palliative radiation
   during the treatment phase of the study, the Sponsor's medical monitor or designee
   must be contacted.

   - Pregnant, lactating, or nursing

   - Any condition which, in the opinion of the investigator, would prevent full
   participation in this trial or the long-term follow-up study, or would interfere with
   the evaluation of the trial endpoints