A Study Comparing Tarlatamab, Durvalumab, Carboplatin, and Etoposide Versus Durvalumab, Carboplatin, and Etoposide in First-line Extensive Stage Small-Cell Lung Cancer (ES-SCLC)

The main objective of the study is to compare the efficacy of tarlatamab in combination with durvalumab, carboplatin and etoposide to the combination of durvalumab, carboplatin and etoposide on prolonging overall survival (OS).

Inclusion Criteria: * Participant has provided informed consent before initiation of any study-specific activities/procedures. * Age ≥ 18 years or ≥ legal age within the country if it is older than 18 years. * Histologically or cytologically documented ES-SCLC (American Joint Committee on Cancer, 2017, Stage IV SCLC \[T any, N any, M1 a/b/c\]), or T3 to T4 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. * Measurable disease as defined per RECIST 1.1. * Suitable to receive carboplatin, etoposide and durvalumab regimen as first-line treatment per investigator clinical assessment. * Minimum life expectancy ≥ 12 weeks. Exclusion Criteria: * Participants can have no history of other malignancy in the last 2 years. * Any symptomatic central nervous system (CNS) metastases, or leptomeningeal disease. * They will have no history of severe or life-threatening events to immune-mediated therapy. * History of arterial thrombosis (eg, stroke or transient ischemic attack) within 6 months prior to first dose of study treatment. * They will have no active autoimmune or inflammatory disorders. * Presence of active human immunodeficiency virus (HIV) or active Hepatitis (B/C) infection. * Evidence or interstitial lung disease (ILD) or active, non-infectious pneumonitis. * History of solid organ transplant. * They will not have had a myocardial infarction and/or symptomatic congestive heart failure (New York Heart Association \> class II) within 6 months prior to first dose of study treatment.