For more information regarding Bristol-Myers Squibb Clinical Trial participation, please visit: www.BMSStudyConnect.com  Inclusion Criteria:  Must have been diagnosed with either Stage IIIA (> 1 mm tumor in lymph node)/B/C/D or Stage IV melanoma by American Joint Committee on Cancer (AJCC) v8 and have histologically confirmed melanoma that is completely surgically resected (free of disease) with negative margins in order to be eligible Participants must have an Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 1 Complete resection must be performed within 12 weeks prior to randomization All participants must have disease-free status documented by a complete physical examination within 14 days prior to randomization and imaging studies within 35 days prior to randomization Tumor tissue must be provided for biomarker analyses  Exclusion Criteria:  History of uveal melanoma Untreated/unresected CNS metastases or leptomeningeal metastases Active, known, or suspected autoimmune disease Participants with serious or uncontrolled medical disorder Prior immunotherapy treatment for any prior malignancy: No prior immunotherapies are permitted Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection 4 weeks prior to screening  Other protocol-defined inclusion/exclusion criteria apply