Purpose

This is a Phase 3, multicenter, randomized, double-blind, placebo-controlled study of niraparib as maintenance in platinum sensitive ovarian cancer patients who have either gBRCAmut or a tumor with high-grade serous histology and who have responded to their most recent chemotherapy containing a platinum agent. Niraparib is an orally active PARP inhibitor. Niraparib or placebo (in a 2:1 ratio) will be administered once daily continuously during a 28-day cycle. Health-related quality of life will be measured by the Functional Assessment of Cancer Therapy - Ovarian Symptom Index (FOSI), European Quality of Life scale, 5-Dimensions (EQ-5D), and a neuropathy questionnaire. Safety and tolerability will be assessed by clinical review of adverse events (AEs), physical examinations, electrocardiograms (ECGs), and safety laboratory values. The primary objective of this study is to evaluate efficacy of niraparib as maintenance therapy in patients who have platinum sensitive ovarian cancer as assessed by the prolongation of progression free survival (PFS).