A Study of Cediranib and Olaparib at the Time Ovarian Cancer Worsens on Olaparib

Inclusion Criteria: * Age 18 years or older * Performance status 2 or less * Ovarian cancer, high grade serous or high grade endometrioid histology subtype * Radiographically documented disease progression per RECIST 1.1 * Progression on olaparib therapy after an initial good response (more than 6 months) * Patients must have adequate bone marrow, renal and hepatic function per local laboratory reference range * Ongoing prior toxicities related to previous treatments recovered to grade 2 or less * LVEF\>50% by echocardiograms or MUGA * Urine dipstick for proteinuria \<2+ * Willing to undergo tumour biopsy pre-treatment * Life expectancy of greater than 3 months * Ability to understand and the willingness to sign a written informed consent document Exclusion Criteria: * Current bowel obstruction * Known brain metastases * Mean QTc \>470 msec (with Bazett's correction) in screening ECG or history of familial long QT syndrome. * Uncontrolled intercurrent illness including, but not limited to hypertension, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * A New York Heart Association classification of III or IV requiring concurrent use of drugs or biologics with proarrhythmic potential. * History of allergic reactions attributed to compounds of similar chemical or biologic composition to olaparib or cediranib * Unable to swallow orally administered medication and/or gastrointestinal disorders likely to interfere with absorption of the study medication. * Myelodysplastic syndrome/acute myeloid leukaemia * Immuno-compromised patients, e.g., patients who are known to be serologically positive for human immunodeficiency virus (HIV), patients with known active hepatitis (i.e.,hepatitis B or C) due to risk of transmitting the infection through blood or other body fluids.