Inclusion criteria:

          -  Written informed consent

          -  Age > 18 years old

          -  Histologically confirmed diagnosis of endometrial cancer or carcinosarcoma of the
             endometrium.

          -  Metastatic disease or locally advanced tumor not amenable to local therapy.

          -  Documented progressive disease before enrolment.

          -  Measurable lesions outside irradiated field or progressive measurable lesions in
             irradiated area

          -  Not eligible for hormonal therapy (because of negative hormone receptor/poor
             differentiation, or after failure of hormonal therapy).

          -  Previous failure of chemotherapy, or refusal to undergo chemotherapy or chemo-naive
             patients not suitable for chemotherapy.

          -  WHO performance 0-1

          -  Adequate organ system function as measured within 28 days prior to administration of
             study treatment, as defined below:

               -  Haemoglobin ≥ 10.0 g/dL, with no blood transfusion in the past 28 days.

               -  Absolute neutrophil count (ANC) ≥ 1.5 x 109/L

               -  Platelet count ≥ 100 x 109/L

               -  Total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN) (not applicable
                  to Gilbert's syndrome)

               -  Aspartate aminotransferase (AST) (Serum Glutamic Oxaloacetic Transaminase (SGOT))
                  / Alanine aminotransferase (ALT) (Serum Glutamic Pyruvate Transaminase (SGPT)) ≤
                  2.5 x ULN unless liver metastases are present in which case they must be ≤ 5x ULN

               -  Patients must have creatinine clearance estimated of ≥51 mL/min estimated using
                  the Cockcroft-Gault equation or 24 hr urine clearance.

          -  Life expectancy of at least 16 weeks.

          -  Measurable disease as defined by RECIST 1.1 criteria

          -  Able to swallow and retain oral medication.

          -  A female is eligible to enter and participate in this study if there is:

        Exclusion criteria:

          -  Participation in another clinical study with an investigational product during the
             last month or previous enrolment in the present study.

          -  Any previous treatment with PARP inhibitor, including olaparib and/or any previous
             treatment with a PD1 or PD-L1 inhibitor

          -  History of another primary malignancy except for malignancy treated with curative
             intent and with no known active disease ≥5 years before the first dose of
             investigational product and of low potential risk for recurrence or adequately treated
             non-melanoma skin cancer, lentigo maligna or carcinoma in situ.

          -  History of leptomeningeal carcinomatosis, symptomatic uncontrolled brain metastases
             (≤2mg/ day corticosteroids started ≥4 weeks prior to treatment is accepted) and spinal
             cord compression (unless received definitive treatment and clinically stable for 28
             days) .

          -  Resting ECG with QTc > 470 msec on 2 or more time points within a 24 hour period or
             family history of long QT syndrome

          -  Concomitant use of known strong or moderate CYP3A inhibitors and inducers.

          -  Any unresolved toxicity NCI CTCAE Grade ≥2 from previous anticancer therapy with the
             exception of alopecia, vitiligo, and the laboratory values defined in the inclusion
             criteria.

          -  Current or prior use of immunosuppressive medication within 14 days before the first
             dose of durvalumab (except intranasal and inhaled corticosteroids or systemic
             prednisone ≤ 10 mg/day)

          -  Major surgery ≤2 weeks of starting study treatment

          -  History of active primary immunodeficiency

          -  Active or prior documented autoimmune or inflammatory disorders, with exception of:
             vitiligo or alopecia, hypothyroidism stable on hormone replacement, any chronic skin
             condition that does not require systemic therapy, celiac disease controlled by diet
             alone

          -  Patients unable to swallow orally administered medication and patients with
             gastrointestinal disorders likely to interfere with absorption of the study
             medication.

          -  Active infection including tuberculosis, hepatitis B/C and HIV

          -  Patients with an expected or known hypersensitivity to olaparib or durvalumab or any
             of the excipients of the products.

          -  Previous allogenic bone marrow transplant or double umbilical cord blood
             transplantation (dUCBT).

          -  Receipt of live attenuated vaccine within 30 days prior to the first dose of IP.

          -  Pregnancy or breastfeeding