Inclusion Criteria:  Histopathologically confirmed diagnosis of NSCLC with PD-L1 expression of ≥1% based on FDA-approved test No prior treatment with checkpoint inhibitors or more than one regimen of chemotherapy including epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) mutation directed therapy for advanced or metastatic disease Disease must have at least 1 measurable target lesion by RECIST 1.1 Adequate major organ functions as evidenced by laboratory findings within 14 days prior to first dose Eastern Cooperative Oncology Group (ECOG) ≤2 and must have a life expectancy of ≥12 weeks  Exclusion Criteria:  History of grade ≥3 hypersensitivity reactions to monoclonal antibodies Participation in another interventional clinical trial within 28 days or less than 5 half-lives of investigational agent before the first dose Recurrent pleural effusion requiring repetitive palliative thoracentesis within 3 months prior to study entry (except patients with a PleurX™ port) Active, known or suspected autoimmune disease or history of immune-mediated toxicity leading to discontinuation of previous checkpoint inhibitor treatment should be administered in (neo)adjuvant setting. Exceptions are for type I diabetes mellitus, hyperthyroidism requiring hormone-replacement or skin only disorders (such as vitiligo, psoriasis, or alopecia) not requiring systemic therapy Active pneumonitis, history of non-infectious pneumonitis that required treatment with steroids, or history of interstitial lung disease Received approved live vaccines within 30 days of planned first dose. Intranasal influenza vaccines (e.g. Flu-Mist) are not allowed, however inactivated viral vaccines or vaccines based on subviral component are allowed Any condition requiring chronic systemic treatment with either corticosteroids (>10 mg daily prednisone equivalents) or other immunosuppressive medications. And any steroids use within 14 days of first dose except for inhaled or topical steroids.  Note: Other protocol-defined Inclusion/Exclusion criteria may apply