Amendment 1 (Version 2): Addition of the timelines between progression and enrolment to target population in Synopsis. -Changes related to weigh based dosing for patients whose weight falls to 30kg or in Changes related to weigh based dosing for patients whose weight falls to 30kg. -Clarification added to inclusion criteria 3, and 4 regarding stage at initial diagnosis and timelines between progression and enrollment respectively, and exclusion criteria 10, and Section 8.7.1 regarding use of sensitive substrates of CYP3A4. -Information added to Study plan and timing of procedures regarding relevant assessments.-Change related to the time of validity of laboratory samples between screening and baseline was from 7 days to 3 days. -clarification added to Section 7.6 Overdose. -Additional information added on Rationale for four cycles of combination therapy followed by durvalumab monotherapy. -Removal of Section 12.7.1.2 Tremelimumab as there will be no tremelimumab monotherapy in the trial. -Information added to Sections 2.7.2, 2.7.2.1, 2.7.2.2 and 2.7.2.3 regarding identified and potential risks for durvalumab, tremelimumab and durvalumab + tremelimumab. -Information added to Section 5 regarding reasons for potential dosing delay. -Additional information added to Section 4.5 regarding AZD1775 dosing. -Addition of a section regarding Patients with a history of Torsades de pointes to the Restrictions Section 4.5.2. -Clarification added to section 7.3.3.3 Nausea and vomiting regarding aprepitant [Emend] and fosaprepitant. - Clarification added to Appendix B Figure 2 AZD1775 + carboplatin therapy dosing schedule. -Addition of Section 8.7.3 Substances known to prolong the ECG QTc interval.

Amendment 2 (Version 3): Treatment Arm C added to protocol – subprotocol for this Arm is included in APPENDIX C. -Clarification to interim analysis description was added in Synopsis section to clarify the action taken in event of a decision to close Arm after stage 1. -Exploratory objective and specification for Arms was added to Section 3.4, Study Objectives. -Clarification added to Section 4.9 on discontinuation of investigational product. - Information added in Section 4.10.2 regarding possible replacement of withdrawn subjects. -Clarification was added in Section 4.10.3 on consent withdrawal. -Time period for collection of adverse events, revised to address events post the defined safety follow-up period. -Information added to Appendix A, Section 2.8 to provide clarity on study design for Arm A. -Clarification added to inclusion criterion 5 in Appendix A, section 4.1 on prohibition of use of granulocyte-colony stimulating factor for neutrophils raising during screening. -Updated Appendix A Table 7 Dosing Modification and Toxicity Management Guidelines for Immune-mediated, Infusion Related, and Non Immune-mediated Reactions (MEDI4736 Monotherapy or Combination therapy with Tremelimumab or Tremelimumab Monotherapy) to version from 1 Nov 2017. -Information was added to Appendix B Section 7.2.2 regarding paternal exposure.

Amendment 3 (Version 4): Protocol synopsis and Section 2.2.1 Rationale for study design were updated to allow expansion of any arm, to a total of 40 eligible subjects, based on Review Committee assessment of data from the first 20 subjects. -Exploratory objectives were updated for clarification and to allow analysis of further biomarkers including circulating tumour DNA (ctDNA) and tumour mutation burden (TMB). -Synopsis Statistical Methods section and Section 9.2 Sample Size Estimate of Master protocol updated to correct typos, include a row in the table for 40 subjects and remove the column for 25%. -Benefit-risk updated with 6 and 12 months OS data. -Methods for assigning treatment groups updated to clarify that parallel recruitment is allowed. -Information added to Section 6.1 to clarify how to follow up if subjects discontinue study treatment prior to PD. -Analysis following expansion added to explain there is no need for further interim analysis in that group of patients and describe planned sensitivity analysis. -Rationale for study design, doses, and control groups updated to include scientific rationale for expanding Arm A. -Durvalumab and tremelimumab dose and treatment regimen justification updated with latest data and durvalumab IB. -Schedule of assessments updated to remove biomarker samples that are not collected (e.g. CTCs), added (e.g. ctDNA) and tighten requirements for tumour biopsy material. Footnotes updated to clarify that some samples are not required in the expansion group (including PK, anti-drug antibodies (ADA) and mRNA). -Schedule of assessments (post-discontinuation) updated regarding PK samples to clarify not required for expansion group. -Updated to reflect the wording on optional exploratory genetic sample informed consent form, consistent with current durvalumab template. -Updated to reflect information included in latest olaparib IB (edition 15). -

Amendment 4 (Version 5): Sections on durvalumab and tremelimumab monotherapies and combined therapy updated as per current IBs in Appendix A. - Dosing Modification and Toxicity Management Guidelines for durvalumab and tremelimumab separated from Appendix A (i.e. Arm A study protocol). -Removal of the requirement to collect PK samples after Cycle 6 in Arm C. -Haematological parameters for ongoing treatment, and guidance for dose modifications revised as per updated Cerelasertib guidance.