Inclusion Criteria:

          1. Has the pathologically-confirmed diagnosis of locally recurrent or metastatic,
             hormone-receptor positive, HER2 negative Breast Cancer.

          2. Age: 18 - 75 years old, postmenopausal women or prepostmenopausal women

          3. Received prior endocrine therapy

          4. One previous line of chemotherapy for advanced/metastatic disease is allowed in
             addition to endocrine therapy.

          5. Eastern Cooperative Oncology Group [ECOG] 0-1

        Exclusion Criteria:

          1. Patients who received prior treatment with any CDK4/6 inhibitor, everolimus or
             fulvestant.

          2. Clinically significant cardiovascular and cerebrovascular diseases,including but not
             limited to severe acute myocardial infarction within 6 months before enrollment,
             unstable or severe angina, Congestive heart failure (New York heart association (NYHA)
             class > 2), or ventricular arrhythmia which need medical intervention.