A Study of Atezolizumab Compared With Gemcitabine Plus (+) Cisplatin or Carboplatin for PD-L1-Selected Participants With Stage IV Squamous Non-Small Cell Lung Cancer (NSCLC) (IMpower111)

Inclusion Criteria:

Histologically or cytologically confirmed Stage IV squamous NSCLC
Tumor programmed death-ligand 1 (PD-L1) expression, as determined by immunohistochemistry (IHC) assay of archival tumor tissue or tissue obtained at screening
No prior treatment for Stage IV squamous NSCLC
Measurable disease as defined by RECIST v1.1
Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1
Adequate hematologic and end-organ function

Exclusion Criteria:

Active or untreated central nervous system (CNS) metastases
Untreated or inadequately treated spinal cord compression
Leptomeningeal disease
Uncontrolled pleural effusion, pericardial effusion, or ascites
Uncontrolled tumor-related pain
Uncontrolled hypercalcemia
Any other malignancies within 5 years except those with negligible risk of metastasis or death
Pregnant or lactating women
Known hypersensitivity to any component of atezolizumab formulation or other study medication
History of autoimmune disease except controlled, treated hypothyroidism or type I diabetes
Prior allogeneic bone marrow or solid organ transplantation
Positive human immunodeficiency virus (HIV) test
Active hepatitis B or C
Active tuberculosis
Significant cardiovascular disease
Severe infection or major surgery within 4 weeks prior to randomization
Use of any approved anti-cancer therapy within 3 weeks prior to treatment
Use of an investigational agent or participation in another clinical trial within 4 weeks prior to randomization
Exposure to oral or IV antibiotics within 2 weeks or live attenuated vaccines within 4 weeks prior to randomization
Prior treatment with cluster of differentiation (CD) 137 agonists or immune checkpoint blockade therapies, anti-programmed death-1 (anti-PD-1), and anti-PD-L1 therapeutic antibodies
Treatment with immunostimulatory agents within 4 weeks or immunosuppressive agents within 2 weeks prior to randomization