Methods
toxicity
DISEASE, METASTATIC DISEASE
This single-center, single-arm phase II study enrolled patients with ER+/HER2- MBC progressed on previous letrozole or anastrozole. Stratified analysis was performed according to the number of chemotherapy regimens for metastatic disease. The primary endpoint was progression free survival (PFS). Secondary endpoints included objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR), overall survival (OS) and toxicity. Patients received apatinib at a starting dose of 500 mg/d and exemestane 25 mg/d on days 1–28 of each 4-week cycle.