Inclusion Criteria:

1. Histologically confirmed stage IIIa/b/c/d or stage IV melanoma
2. Complete resection of Stage III disease that is documented on the surgical and pathology reports or complete resection of Stage IV disease with margins negative for disease that is documented on the pathology report
3. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1

Exclusion Criteria:

1. Prior malignancy active within the previous 3 years, except for locally curable cancers that have been apparently cured
2. Any significant acute or chronic medical illness that is uncontrolled
3. History of ocular/uveal melanoma
4. Active, known or suspected autoimmune disease
5. Systemic treatment with either corticosteroids (> 10 mg daily prednisone or equivalent) or other immunosuppressive medications within 14 days of study drug administration. Inhaled or topical steroids and adrenal replacement steroid doses > 10 mg daily prednisone or equivalent, are permitted in the absence of active autoimmune disease.

Other protocol-defined inclusion/exclusion criteria apply