This is a Phase II, open-label, non-comparative, international, multicenter study to assess the efficacy and safety of olaparib when given orally twice daily (bd) in participants with advanced BRCA1- or BRCA2- associated breast cancer. Two sequential participant cohorts will receive continuous oral olaparib in 28-day cycles. The first cohort will receive 400 mg bd and the second cohort will receive 100 mg bd.
