Inclusion Criteria:

          -  Histologically documented non-keratinizing locally advanced recurrent or metastatic
             NPC.

          -  Must be resistant to platinum-based chemotherapy (defined as progression on or after
             platinum-based chemotherapy given in the recurrent/metastatic setting).

          -  May have received at least 1 prior therapy for recurrent or metastatic disease, up to
             2 prior systemic therapies.

          -  An archival tumor specimen or newly obtained tumor sample may be submitted at
             screening/baseline (a fresh tumor sample is preferred), unless agreed differently
             between Novartis and the Investigator.

          -  At least 1 measurable lesion (as per RECIST v1.1) progressing or new since last
             anti-tumor therapy.

          -  Prior treated brain or meningeal metastases must be without MRI evidence of
             progression for at least 8 weeks and off systemic steroids for at least 2 weeks prior
             to screening/baseline.

          -  Patient must be willing to undergo testing for human immunodeficiency virus (HIV) if
             not tested within the past 6 months. If HIV+ positive, patient will be eligible if:
             his/ her CD4+ count ≥ 300/μL; his/her viral load is undetectable; he/she is currently
             receiving highly active antiretroviral therapy (HAART).

        Exclusion Criteria:

          -  History of severe hypersensitivity reactions to other mAbs

          -  Active autoimmune disease or a documented history of autoimmune disease, except
             vitiligo or resolved asthma/atopy that is treated with broncho-dilators.

          -  Active HBV or HCV infections requiring therapy.

          -  Prior PD-1- or PD-L1-directed therapy or any therapeutic cancer vaccine.

          -  Patients receiving systemic treatment with any immunosuppressive medication.

          -  Use of any vaccines against infectious diseases (e.g. varicella, pneumococcus) within
             4 weeks of initiation of study treatment.

        Other protocol-define inclusion/exclusion may apply.