Niraparib Maintenance in HRD-Positive Advanced Ovarian Cancer Following Front-Line Chemotherapy + Bevacizumab

Inclusion Criteria:

1. The written informed consent form shall be signed before proceeding with anystudy-related procedure.
2. Participants shall be a female, aged 18 years or older.
3. Histologically confirmed primary high-grade epithelial ovarian cancer, fallopian tubecarcinoma or primary peritoneal carcinoma。
4. FIGO staging is Stage III or IV.
5. Patients who have undergone primary tumor reductive surgery or intermittent tumorreductive surgery (patients who have used neoadjuvant therapy), regardless ofpostoperative residual lesion status
6. Participants must have received, prior to enrollment, a minimum of 2 cycles ofbevacizumab in combination with platinum-based chemotherapy.
7. Participants must have completed front-line, platinum-based chemotherapy with CR, PR,or NED assessed by RECIST v1.1.
8. Participant must have either CA-125 in the normal range or CA-125 decrease by morethan 90% during front-line therapy that is stable for at least 7 days (ie, no increase > 15% from nadir).
9. Participants must have first study treatment dose within 12 weeks of the first day ofthe last cycle of chemotherapy.
10. Genetic testing of tumor tissue indicates HRD positive or germline/somatic BRCAmutation prior to enrollment.
11. Participant must have an Eastern Cooperative Oncology Group (ECOG) score ≤2.
12. Organ function is in good condition, including: Hemoglobin ≥100 g/L; White blood cellcount ≥3×10^9/L; Neutrophil count ≥1.5×10^9/L; Platelet count ≥100×10^9/L; Totalbilirubin is not more than 1.5 times the normal upper limit; ALK, AST and ALT are notmore than 2.5 times their normal upper limit, and with existence of hepaticmetastasis, these values must not be more than 5 times their normal upper limit; Serumcreatinine is not more than 1.5 times the normal upper limit.

Exclusion Criteria:

1. Histopathological types other than high-grade ovarian/tubal/peritoneal cancer ormetastatic ovarian cancer.
2. Receipt of other targeted drugs as maintenance therapy, excluding PARP inhibitors.
3. Concurrent severe respiratory or hematologic disorders, poorly controlled diabetes,uncontrolled hypertension of Grade 2 or higher, NYHA Class III or higher congestiveheart failure, unstable angina, recent myocardial infarction within the past 6 months,or other circulatory system diseases.
4. Any other significant complications or functional impairments in organ systems, asdetermined by the investigator, that may affect the safety of the participant orinterfere with the evaluation of the investigational drug.
5. Expected survival less than 3 months.
6. Other than ovarian cancer, the participant has been diagnosed a second primary tumorwithin the past 2 years and currently undergoing treatment.