A Vaccine (MV-s-NAP) for the Treatment of Patients With Invasive Metastatic Breast Cancer

Inclusion Criteria: * Age \>= 18 years * COHORT 1 ONLY: Pathologically confirmed invasive breast adenocarcinoma with documented estrogen receptor (ER)/progesterone receptor (PR) /HER2 status and radiographic evidence of distant metastatic disease * COHORTS 2 \& 3 ONLY: Pathologically confirmed invasive breast adenocarcinoma with documented ER/PR/HER2 status and radiographic evidence of distant metastatic or recurrent disease * COHORT 1 ONLY: Radiographic evidence of distant metastatic disease (using 7th edition American Joint Committee on Cancer \[AJCC\] criteria) with two discrete sites of measurable disease * COHORTS 2 \& 3 ONLY: Radiographic evidence of distant metastatic or recurrent disease (using 8th edition AJCC criteria) with at least one site of measurable disease * Prior therapies: * Patients with ER/PR positive, HER2 negative breast cancer must have progressed through at least one prior cytotoxic regimen for advanced disease and no longer be candidates for standard endocrine therapy or combination of endocrine therapy with other agents such as CDK4/6 inhibitors * Patients with HER2 positive breast cancer irrespective of ER/PR status must have received or no longer be candidates for HER2 directed therapy with trastuzumab or pertuzumab * Patients with ER/PR/HER2 negative breast cancer must have progressed through at least one prior cytotoxic regimen for advanced disease * COHORT 1: At least one site of recurrent/metastatic disease that measures \> 1 cm in gre…