Alisertib With or Without Fulvestrant in Treating Patients With Locally Advanced or Metastatic, Endocrine-Resistant Breast Cancer

Inclusion Criteria: * PRE-REGISTRATION ELIGIBILITY * Post-menopausal defined as * Age \>= 60 and amenorrhea \> 12 consecutive months, OR * Age \< 60 and amenorrhea \> 12 consecutive months without another cause and documented follicle stimulating hormone (FSH) level of \> 35 mIU/mL, OR * Previous bilateral oophorectomy * Histologic proof of metastatic or locally advanced, unresectable breast cancer * History of ER positive (+) (\>= 10% of cells positive on hematoxylin and eosin stain \[H\&E\]), HER2 negative (-) breast cancer disease, either as a * History of primary, operable ER+/HER2- invasive breast cancer OR * History of de novo metastatic breast cancer that is ER+/HER2- * Note: HER2- (negative) disease defined as one of the following: * HER2 immunohistochemistry (IHC) expression of 0, 1+ and in-situ hybridization (ISH) non-amplified * HER2 IHC expression of 0, 1+ and ISH not done * HER2 IHC expression of 2+ and ISH non-amplified * IHC not done and ISH non-amplified * Prior treatment * No more than two prior chemotherapy regimens in the metastatic setting * Prior treatment with fulvestrant in the metastatic setting is required, except for patients with a history of ER-negative metastatic breast cancer * Unlimited prior endocrine therapy regimens in the metastatic setting are allowed * No prior treatment with an aurora Kinase inhibitor (either an aurora A or pan-aurora kinase inhibitor) * Disease that is measurable where:…