NEoadjuvant Olaparib Combination OvArian Cancer Targeted Study

The goal of this phase 2 clinical trial is to learn if the three treatments olaparib, durvalumab and bevacizumab can treat participants with a diagnosis of stage 4 high grade serous ovarian cancer that is too advanced to undergo upfront surgery. The main questions it aims to answer are: Is the treatment able to shrink the cancer sufficiently for participants to undergo surgery? Is the combination of treatments safe in this neoadjuvant (before surgery) setting? This is a single arm study with no comparator arm. Participants will receive the treatment up to 3 cycles with each drug given as follows in a 28-day cycle: Olaparib orally on a twice daily continuous dosing schedule Durvalumab given intravenously on day 1 Bevacizumab given intravenously on day 1 and 15 (Day 15 omitted in C3) Participants will be assessed throughout the study for safety and efficacy endpoints