Inclusion Criteria:  Women aged 18 years or older Histologically confirmed epithelial ovarian cancer, carcinoma of fallopian tube or primary peritoneal carcinoma Having received one line of platinum-based chemotherapy, and clinically CR or PR to this line of chemotherapy Understand the protocol, and Written informed consent before any study-related procedure  Exclusion Criteria:  Participating in other clinical trials at the same time Having sever or uncontrolled diseases that will influence the study, according to the judgement of investigators Having other malignant tumors (other than breast cancer with BRCA mutation) Pregnancy or breast feeding, or planning a pregnancy during the study Unable to visit on time Patients who are allergic to the study drug or drug components