Avelumab in First-line NSCLC (JAVELIN Lung 100)

Inclusion Criteria:

* Male or female subjects aged greater than or equal to (\>=) 18 years
* With Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 to 1 at trial entry
* At least 1 measurable tumor lesion
* With histologically confirmed metastatic or recurrent (Stage IV) non-small cell lung cancer (NSCLC)
* With availability of a recently-obtained, formalin-fixed, paraffin-embedded (FFPE) tissue sample containing tumor (biopsy from a non-irradiated area preferably within 6 months) or a minimum number of 10 (preferably 25) unstained tumor slides cut within 1 week, and suitable for PD-L1 expression assessment
* Subjects must not have received any treatment for systemic lung cancer, and have an estimated life expectancy of more than 12 weeks
* Other protocol defined criteria could apply

Exclusion Criteria:

* Subjects whose disease harbors a EGFR mutation, or anaplastic lymphoma kinase (ALK) rearrangement are not eligible.
* Other exclusion criteria include prior therapy with any antibody or drug targeting T cell coregulatory proteins, concurrent anticancer treatment, or immunosuppressive agents
* Known severe hypersensitivity reactions to monoclonal antibodies (Grade \>= 3 NCI CTCAE v 4.03), history of anaphylaxis, or uncontrolled asthma (that is, 3 or more features of partially controlled asthma), and persisting toxicity related to prior therapy of Grade \> 1 NCI-CTCAE v 4.03.
* Subjects with brain metastases are excluded, except those meeting the following criteria: brain metastases that have been treated locally and are clinically stable for at least 2 weeks prior to randomization, subjects must be either off steroids or on a stable or decreasing dose of \<= 10 mg daily prednisone (or equivalent), and do not have ongoing neurological symptoms that are related to the brain localization of the disease.
* Other protocol defined criteria could apply