To evaluate the efficacy, safety tolerability of maintenance therapy with Fluzoparib(A PARP inhibitor) versus placebo in Chinese patients with recurrent ovarian cancer who achieved a complete response (CR) or partial response (PR) after platinum-based chemotherapy

Inclusion Criteria:

1. Histologically diagnosed high-grade serous or endometrioid ovarian cancer (including primary peritoneal and fallopian tube cancer)
2. Completion of ≥2 previous platinum-containing regimens
3. Complete response (CR) or partial response (PR) achieved with last platinum-based chemotherapy regimen as determined by investigator
4. Ability to be randomized ≤8 weeks after last dose of platinum

Exclusion Criteria:

1. Prior treatment with a poly (ADP-ribose) polymerase (PARP) inhibitor
2. Patients who have received other study drug treatment within 4 weeks prior to the first administration(< 5 elimination half-lives of the study drug molecular targeted anti-cancer drugs).
3. Patients with clinical symptoms of cancer ascites, pleural effusion, who need to drainage, or who have undergone ascites drainage within 2 months prior to the first administration.