A Study of Tiragolumab Plus Atezolizumab Compared With Placebo Plus Atezolizumab in Participants With Completely Resected Non-small Cell Lung Cancer Who Have Received Adjuvant Platinum-based Chemotherapy

Inclusion Criteria:

• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

• Histological or cytological diagnosis of Stage IIB, IIIA, and select IIIB NSCLC ofeither non-squamous or squamous histology

• Participants must have had complete resection of NSCLC

• Participants must have received between one to four cycles of adjuvanthistology-based platinum doublet chemotherapy

• Participants must have recovered adequately from surgery and from adjuvantchemotherapy

• Tumor cell PD-L1 expression at >/= 1%

• Adequate hematologic and end-organ function.

Exclusion Criteria:

• Any history of prior NSCLC within the last 5 years

• Any evidence of residual disease or disease recurrence following surgical resectionof NSCLC, or during or following adjuvant chemotherapy

• NSCLC known to have mutation in the epidermal growth factor receptor (EGFR) gene oran anaplastic lymphoma kinase (ALK) fusion oncogene