Primary objective of this study is to evaluate the efficacy of AZD2811 and durvalumab in patients who have not progressed following induction therapy with platinum-based chemotherapy combined with durvalumab.~This is an open-label, single arm study. Patients will be treated in an induction phase with platinum-based induction therapy and durvalumab. At the end of this induction period, participants will be assessed for disease progression, per RECIST v1.1.~Participants who have not progressed per RECIST v1.1 at the end of the induction phase will roll over into the maintenance phase of the trial, where patients will commence AZD2811 and durvalumab combination.~Participants will be treated with AZD2811 and durvalumab as maintenance therapy until confirmed progressive disease, start of non-protocol defined anticancer therapy, unacceptable toxicity, or withdrawal of consent.~If study intervention is permanently discontinued, the participant will remain in the study to be evaluated for safety assessment, as well as for confirmed disease progression and for survival.~Targeted population are adult patients (aged ≥18 years) with histologically or cytologically documented extensive disease (American Joint Committee on Cancer Stage (7th edition) IV SCLC [T any, N any,M1 a/b]), or T3-4 due to multiple lung nodules that are too extensive or have tumor/nodal volume that is too large to be encompassed in a tolerable radiation plan. Patients must have WHO/ECOG performance status of 0 or 1.~Tumor assessments will be performed at Screening as baseline with follow-up every 6 weeks ± 1 week for the first 36 weeks, and then every 8 weeks ±1 week until confirmed objective disease progression.
A Phase II Multicenter, Open-Label, Single Arm Study to Determine the Efficacy, Safety and Tolerability of AZD2811 and Durvalumab Combination as Maintenance Therapy After Induction with Platinum-Based Chemotherapy Combined with Durvalumab, for the First-Line Treatment of Patients with Extensive Stage Small-Cell Lung Cancer.