A Trial to Evaluate the Safety of Niraparib Tablets in Adult Female Participants With Advanced or Relapsed Epithelial Ovarian Cancer

Inclusion Criteria: * Female participants with ≥18 years of age, able to understand the study procedures and agree to participate in the study by providing written informed consent. * Histologically confirmed epithelial ovarian cancer. * Eligible for active study drug treatment according to the approved label - as monotherapy for the maintenance treatment of adult participants with advanced epithelial (International Federation of Gynecology and Obstetrics \[FIGO\] stage III and IV) high-grade ovarian, fallopian tube or primary peritoneal cancer who are in response (complete or partial) following completion of first-line platinum-based chemotherapy. * as monotherapy for the maintenance treatment of adult participants with platinum-sensitive relapsed high grade serious epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in response (complete or partial) to platinum-based chemotherapy. * Laboratory complete blood count (CBC) criteria (Absolute neutrophil count ≥1,500/microliters \[μL\]; Platelets ≥100,000/μL; Hemoglobin ≥9 grams per decilitre \[g/dL\]). * Adequately controlled hypertension basis on investigator's discretion. * Women of childbearing potential must be ready to use contraceptive measures to avoid pregnancy during study period and until 180 days after the last dose. Exclusion Criteria: * Participant is pregnant, breastfeeding, or expecting to conceive children while receiving study treatment and for up to 180 days after the last dose of study treatment. * Participant had known, active hepatic disease, known case of end-stage renal disease (ESRD), known case of serious, uncontrolled medical disorder, any known history or current diagnosis of Myelodysplastic syndrome (MDS) or Acute myeloid leukemia (AML). * Any previous polymerases inhibitor (PARPi) treatment. * Participant with concomitant serious uncontrolled medical illness. * Participant is receiving niraparib for use that is not according to the approved label. * Participant with either the history of hypersensitivity to excipients of the study drug or to drugs with a similar chemical structure or class to the study drug. * Participant with a previously or currently diagnosed MDS/ AML or pneumonitis. * Participants who have not recovered sufficiently from prior surgery or anticancer treatment. * Participants who have known history of hepatitis B or hepatitis C. * Participant with active infection such as tuberculosis (TB) Prior/concurrent clinical study experience. * Participation in another clinical study with a study drug administered in the last 3 months. * Judgment by the investigator that the participant should not take part in the study if the participant is unlikely to comply with study procedures, restrictions and requirements. * Previous enrolment in the present study.