Inclusion Criteria:

          -  Metastatic disease or locally advanced, unresectable disease.

               -  Has histopathologically confirmed gastric or GEJ adenocarcinoma with documented
                  disease progression after 0-2 prior lines of systemic therapy

               -  Has histopathologically confirmed nonsquamous or squamous NSCLC with documented
                  disease progression after 0-3 prior lines of systemic therapy

               -  Has histopathologically confirmed transitional cell carcinoma of the urothelium
                  (bladder, urethra, or renal pelvis) with documented disease progression after 1-3
                  prior lines of systemic therapy

               -  Has histologically confirmed biliary tract adenocarcinoma with documented
                  progression after 1-2 prior lines of systemic therapy

          -  Availability of tumor tissue for biomarker analysis from a newly obtained core or
             excisional biopsy or willing to undergo a tumor biopsy. For first line NSCLC
             participants only, PD-L1 expression should be 1% or higher.

          -  Have an Eastern Cooperative Oncology Group Performance Status of 0 or 1.

          -  Has adequate organ function.

          -  Have an anticipated life expectancy of ≥3 months.

        Exclusion Criteria:

          -  Have known brain metastases.

          -  Has received ≥3 lines of prior systemic therapy for gastric or GEJ adenocarcinoma and
             BTC or ≥4 lines for NSCLC or urothelial cancer.

          -  Has active autoimmune disease.

          -  Known human immunodeficiency virus (HIV) infection.

          -  Known active hepatitis B or hepatitis C infection.

          -  Has received any previous systemic therapy targeting vascular endothelial growth
             factor (VEGF) or VEGF receptor, or programmed death (PD) 1 or PD-ligand 1/2 signaling
             pathways.

          -  Have received a live vaccine within 30 days prior to enrollment. Seasonal flu vaccines
             that do not contain live virus are permitted.

          -  Have had a serious or non-healing wound, ulcer, or bone fracture within 28 days prior
             to enrollment.

          -  Have an elective or a planned major surgery during the course of the trial or has
             undergone major surgery within 28 days prior to enrollment.