A Study of Atezolizumab Plus Carboplatin and Etoposide With or Without Tiragolumab in Patients With Untreated Extensive-Stage Small Cell Lung Cancer

Inclusion Criteria:

Histologically or cytologically confirmed extensive-stage small cell lung cancer (ES-SCLC)
No prior systemic treatment for ES-SCLC
Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1
Measurable disease, as defined by Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1)
Adequate hematologic and end-organ function
Treatment-free for at least 6 months since last chemo/radiotherapy, among those treated (with curative intent) with prior chemo/radiotherapy for limited-stage SCLC

Exclusion Criteria:

Symptomatic or actively progressing central nervous system (CNS) metastases
Malignancies other than small cell lung cancer (SCLC) within 5 years prior to randomization, with the exception of those with a negligible risk of metastasis or death treated with expected curative outcome
Active or history of autoimmune disease or immune deficiency
History of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, or idiopathic pneumonitis, or evidence of active pneumonitis on screening chest computed tomography (CT) scan
Positive test result for human immunodeficiency virus (HIV)
Active hepatitis B or hepatitis C
Severe infection at the time of randomization
Treatment with any other investigational agent within 28 days prior to initiation of study treatment
Prior treatment with CD137 agonists or immune checkpoint blockade therapies, anti-cytotoxic T lymphocyte-associated protein 4 (anti-CTLA-4), anti-TIGIT, anti-PD-1, and anti-PD-L1 therapeutic antibodies
Treatment with systemic immunostimulatory agents within 4 weeks or 5 drug elimination half-lives prior to randomization