Metronomic Capecitabine Plus Aromatase Inhibitor for First Line Treatment in HR(+), Her2(-) Metastatic Breast Cancer

Inclusion Criteria:

* Adult women with locoregionally recurrent or metastatic disease not amenable to curative therapy
* Confirmed diagnosis of ER positive/Her2-negative breast cancer
* No prior systemic anti-cancer therapy for locoregionally recurrent or metastatic disease
* Any menopausal status, but premenopausal or perimenopausal patients are required to receive LHRHa treatment
* Measurable disease defined by RECIST version 1.1, or bone-only disease
* Eastern Cooperative Oncology Group (ECOG) 0-2, and life expectancy ≥ 3 months
* Adequate organ and marrow function
* Resolution of all toxic effects of prior therapy or surgical procedures

Exclusion Criteria:

* Patients who have progressed within 2 years of adjuvant endocrine therapy
* Patients who have not received prior endocrine therapy and are eligible to receive fulvestrant as initial therapy
* Patients with advanced, symptomatic, visceral spread that are at risk of life threatening complication in the short term
* Known uncontrolled or symptomatic central nervous system metastases
* Diagnosis of any other malignancy within 3 years prior to randomization (except adequately treated basal or squamous cell skin cancer or cervical carcinoma in situ)
* Serious uncontrolled intercurrent infections or intercurrent medical or psychiatric illness