This is a Phase II, open-label, multicenter, randomized umbrella study to evaluate the efficacy of cytoreductive surgery and Niraparib maintenance in participants with platinum-sensitive secondary recurrent ovarian cancer. Cohort 1 will focus on participants without prior use of PARP inhibitor, and without prior secondary cytoreduction (SCR) when first recurrence. Cohort 2 will focus on participants with prior use of PARP inhibitor, but without prior SCR when first recurrence. Cohort 3 will focus on participants with SCR when first recurrence, but without prior use of PARP inhibitor.

This exploratory trial is to compare the efficacy of secondary cytoreductive surgery followed by chemotherapy and Niraparib maintenance, versus chemotherapy alone followed by Niraparib maintenance in patients with platinum-sensitive secondary recurrent ovarian cancer.

Inclusion Criteria:

• Age ≥18 years to ≤ 75 years

• Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2

• Patients with platinum-sensitive, secondary relapsed epithelial ovarian, primary peritoneal, or fallopian tube cancer.

• Front-line or second-line treatment may have included maintenance therapy (i.e. bevacizumab, PARP inhibitor)

  • Cohort 1 and Cohort 3: No prior use of PARP inhibitor.
  • Cohort 2: Prior use of PARP inhibitor.
  • Cohort 3: No prior use of PARP inhibitor.

• Secondary cytoreductive surgery (SCR) when first recurrence

  • Cohort 1 and Cohort 2: Never received SCR
  • Cohort 2: Never received SCR
  • Cohort 3: Received SCR

• Assessed by the experienced surgeons, complete resection of all recurrent disease is possible. Single or localized lesions identified by CT, or MRI, or positron emission tomography/computed tomography (PET/CT). PI and Co-PI reach consensus if extensive lesions or carcinomatosis.

• It can be included if single lesion outside the peritoneal cavity can be resected.

• No more than 3 disease lesions by central-reviewed PET/CT imaging if the participated center has never participated in any surgical trials on ovarian cancer before.

• Patients who have given their signed and written informed consent and their consent.

Exclusion Criteria:

• Patients with borderline tumors as well as non-epithelial tumors.
• Patients for interval-debulking, or for second- or third-look surgery, or palliative surgery planned.
• Impossible to assess the resectability. Radiological signs suggesting complete resection is impossible.
• Patients who have received more than two previous regimen of chemotherapy (maintenance is not considered a third regimen).
• Third relapse or more.
• Patients with second or other malignancies who have been treated by surgery, if the treatment might interfere with the treatment of relapsed ovarian cancer or if major impact on prognosis is expected.
• Progression during chemotherapy or recurrence within 6 months after second-line platinum-based therapy
• Any contradiction not allowing surgery and/or chemotherapy and/or or Niraparib
• Accompanied by hypoxia serious chronic obstructive pulmonary disease
• Uncontrolled hypertension, cerebrovascular accident/ Stroke, myocardial infarct, unstable angina, untreated thrombosis, chronic congestive heart failure, or serious arrhythmia in need of medicine.
• Severe hepatitis, history of liver disease, nephrotic syndrome, renal insufficiency
• Active ulcer history, abdominal wall fistula, perforation of gastrointestinal tract, or Intra-abdominal abscess, or simultaneously apply treatment/prevent ulcers therapy.
• Uncontrolled diabetes
• Uncontrolled epilepsy need long-term antiepileptic treatment.
• Any medication induced considerable risk of surgery, e.g. estimated bleeding due to oral anticoagulating agents.
• ≥3 grade anemia, neutropenia or thrombocytopenia due to chemotherapy, and lasted for more than 4 weeks
• Patients with a known hypersensitivity to Niraparib or any of the excipients of the product.