Neoadjuvant DPX-Survivac Aromatase Inhibition, Radiotherapy or Cyclophosphamide in HR+HER2- Breast Cancer

Inclusion Criteria:

1. Patients must provide informed consent prior to any study-specific procedures and be able to understand and be willing to sign an informed consent document. Results of standard-of-care tests or examinations performed prior to obtaining informed consent and prior to treatment may be used for screening assessments rather than repeating such evaluations if within 30 day of day 1.
2. Women with resectable, non-metastatic breast cancer that is \>1 cm, hormone receptor positive, HER2 negative, Ki67\>10%.
3. HER2 negative is defined as:

   0-1+ HER2 expression by immunohistochemistry (IHC) OR Fluorescence in situ hybridization (FISH) negative OR HER2 2+ and FISH negative
4. Patients must be at least 28 days post systemic steroids prior to enrollment.
5. Patients must be at least 18 years of age.
6. Patients must have Eastern Cooperative Oncology Group (ECOG) Performance Status Score of ≤ 1
7. Adequate laboratory values within 30 days of enrollment defined as follows:

   1. White blood cell (WBC) ≥ 3000/mm3
   2. Hemoglobin (Hgb) ≥ 9 g/dL
   3. Neutrophil count ≥ 1500/mm3
   4. Lymphocyte count ≥ 1000/mm3
   5. Platelet count ≥ 75,000/mm3
   6. Serum creatinine ≤ 2.0 mg/dL or creatinine clearance \> 60 ml/min
   7. Total bilirubin ≤ 1.5 mg/dL
   8. Aspartate aminotransferase (AST)/Serum glutamic oxaloacetic transaminase (SGOT) ≤ 2 times the ULN-
8. Patients must have recovered from major infections and, in the opinion of the investigator, do not have any significant active concurrent medical illnesses precluding protocol treatment.
9. The effects of DPX-Survivac on the developing human fetus are unknown. Women on the trial should be post-menopausal based on the NCCN definition of menopause
10. For patients in Arm B only, they must be able to undergo MR imaging as determined by treating physician using the standard Radiation Oncology MR screening process

Exclusion Criteria:

1. Patients may not be receiving any other investigational agents or on concurrent clinical trials while on during the clinical trial period.
2. History of allergic reactions attributed to compounds of similar chemical or biologic composition to DPX-Survivac.
3. Pregnant and pre-menopausal women are excluded from this study because to keep anti-endocrine therapy consistent between patients.
4. Known history of human immunodeficiency virus (HIV) infection, hepatitis B, or hepatitis C.
5. Uncontrolled autoimmune disease. Autoimmune disease allowed if controlled (with or without treatment) for the last 12 months.
6. Patients may not have received or plan to receive neoadjuvant systemic chemotherapy. 7) Patients unable to receive an aromatase inhibitor

8\) Prior radiation to the affected breast 9) Previous cancers except for non-melanoma skin cancers or high risk cervical lesions in the past 5 years.

10\) Previous breast cancer, tamoxifen, or aromatase inhibitor use. 11) Previous investigational immune therapy use-