For more information regarding Bristol-Myers Squibb Clinical Trial participation, please visit: www.BMSStudyConnect.com Inclusion Criteria: - Histologically confirmed metastatic 1L Stage IV non-small cell lung cancer (NSCLC) of squamous or nonsquamous histology - No prior systemic anti-cancer treatment given as primary therapy for advanced or metastatic NSCLC - Measurable disease as per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 - Eastern Cooperative Oncology Group (ECOG) performance status 0-1 - A formalin-fixed, paraffin-embedded (FFPE) tumor tissue block or a minimum of 20 unstained slides of tumor tissue obtained during screening or prior to enrollment - Life expectancy of at least 3 months at the time of first dose Exclusion Criteria: - Participants with epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), or c-ros oncogene 1 (ROS-1) mutations which are sensitive to available targeted inhibitor therapy. Participants with nonsquamous histology and unknown EGFR, ALK, or ROS-1 status are also excluded - Participants with known B-rapidly accelerated fibrosarcoma proto-oncogene (BRAF) V600E mutations that are sensitive to available targeted inhibitor therapy. Participants with unknown or indeterminate BRAF mutation status are eligible. - Untreated central nervous system metastases - Leptomeningeal metastases (carcinomatous meningitis) - Concurrent malignancy requiring treatment - Active, known, or suspected autoimmune disease - Interstitial lung disease - Uncontrolled or significant cardiovascular disease Other protocol-defined inclusion/exclusion criteria apply