Inclusion Criteria: - Females with a histologically confirmed diagnosis of breast cancer that is metastatic or locally advanced (locally advanced tumors must not be amenable to surgery or radiation therapy with curative intent) with the following pathological characteristics determined locally: estrogen receptor positive, Human Epidermal Growth Factor Receptor 2 (HER-2) negative, Ki67 (a tumor marker) ≥ 15% - Post-menopausal - With advanced breast cancer whose disease was refractory to previous letrozole or anastrozole - Has at least one confirmed measurable metastatic lesion - Has a performance status ≤ 1 on the Eastern Cooperative Oncology Group (ECOG) performance scale - Has a life expectancy of at least 3 months - Adequate organ function Exclusion Criteria: - Is receiving any other concurrent systemic tumor therapy, including hormonal agents and HER-2 inhibitors - Previously received rapamycin or rapamycin analogs, including ridaforolimus, temsirolimus, or everolimus - Received prior treatment with Insulin-like Growth Factor 1 Receptor (IGF-1R) inhibitors, Phosphatidylinositol 3-Kinase (PI3K) inhibitors, or other experimental agents that target PI3K, Protein Kinase B (AKT), or Mammalian Target of Rapamycin (mTOR) pathway - Is receiving chronic corticosteroids administered at doses greater than those used for normal replacement therapy - Has active brain metastasis or leptomeningeal carcinomatosis; patients with adequately treated brain metastases are eligible if they meet certain criteria - Known allergy to macrolide antibiotics - Has an active infection requiring antibiotics - Significant or uncontrolled cardiovascular disease - Poorly controlled Type 1 or 2 diabetes - Is known to be Human Immunodeficiency Virus (HIV) positive - Has a known history of active Hepatitis B or C