This clinical trial is focused on studying a type of lung cancer known as non-small cell lung cancer (NSCLC). The study is investigating the effectiveness of two treatments: atezolizumab and tiragolumab, compared to another treatment called durvalumab. Atezolizumab is also known by its code name RO5541267, and durvalumab is known as MEDI4736. These treatments are given as solutions through an intravenous (IV) infusion, which means they are administered directly into the bloodstream through a vein.

The purpose of the study is to evaluate how well the combination of atezolizumab and tiragolumab works compared to durvalumab in patients with locally advanced, unresectable stage III NSCLC. “Unresectable” means that the cancer cannot be removed with surgery. The study will look at how long patients live without the cancer getting worse, which is known as progression-free survival. This will be assessed by an independent review facility, which is a group of experts who will review the results.

Participants in the study will receive their assigned treatment for up to 52 weeks. The study will monitor the patients’ health and the progression of their cancer during this time. Some participants may receive a placebo, which is a substance with no active medication, to compare the effects of the actual treatments. The study aims to provide valuable information on the best treatment options for patients with this type of lung cancer.