Olaparib maintenance monotherapy in platinum-sensitive, relapsed ovarian cancer without germline BRCA mutations: OPINION Phase IIIb study design.

The poly(ADP-ribose) polymerase inhibitor olaparib (Lynparza™) is approved for maintenance treatment of platinum-sensitive relapsed ovarian cancer. OPINION is a single-arm, open-label, multicenter, Phase IIIb study to assess the efficacy and safety of olaparib tablet maintenance therapy in women with high-grade serous or endometrioid platinum-sensitive relapsed ovarian cancer without a germline BRCA1 or BRCA2 mutation. Eligible patients should have received ≥2 prior lines of platinum-based chemotherapy and be in complete or partial response following their most recent course or have no evidence of disease. Patients will receive olaparib tablets (300 mg twice daily) until disease progression, unacceptable toxicity or another discontinuation criterion. The primary end point is investigator-assessed progression-free survival; secondary end points include progression-free survival according to tumor homologous recombination deficiency status. Clinical trial registration: NCT03402841.