Olaparib Maintenance Treatment Versus Placebo in Patients With PSR Ovarian Cancer Who Are in CR or PR to Platinum-based Chemotherapy and Whose Tumours Carry sBRCAm or HRR-associated Genes Mutations

Inclusion Criteria: * Patients must be ≥ 18 years of age * Histologically diagnosed relapsed high grade epithelial ovarian cancer (including primary peritoneal and/ or fallopian tube cancer) * Documented deleterious or suspected deleterious somatic BRCA 1 and/or BRCA 2 somatic mutation or evidence of non- BRCA HRR-associated gene mutation in the tumour. * At least 2 previous lines of platinum containing therapy prior to randomisation. * CA-125 measurements prior to randomised treatment * Patients must have normal organ and bone marrow function measured within 28 days of randomisation * Eastern Cooperative Oncology Group (ECOG) performance status 0-1 * Postmenopausal or evidence of non-childbearing status for women of childbearing potential * Patient is willing and able to comply with the protocol for the duration of the study including undergoing treatment and scheduled visits and examinations * Provision of a blood sample for cfDNA biomarker analysis in Pre-Screening Part 1 * Formalin fixed, paraffin embedded (FFPE) tumour sample from the primary or recurrent cancer must be available for central testing. If archival tumour sample is not available tumour sample from fresh biopsy is acceptable, for all patients eligible to participate in Pre-Screening part 2. Exclusion Criteria: * Documented germline mutation in BRCA1 and/or BRCA2 that is predicted to be deleterious or suspected deleterious (known or predicted to be detrimental/lead to loss of function). * Patients who have…