Inclusion Criteria:

          -  (Part 1 only) Have a histologically or cytologically confirmed diagnosis of advanced
             solid tumor that has relapsed or is refractory to standard curative or palliative
             therapy or has a contraindication to standard therapy.

          -  (Part 2 only) Cohort 1: Have histologically or cytologically confirmed diagnosis of
             Stage IV squamous NSCLC and have not received prior chemotherapy or immunotherapy for
             metastatic disease and are not known to be PD-L1 positive (known high PD-L1 expression
             defined as Tumor Proportion Score [TPS] greater than or equal to 50%). Patients with
             known sensitizing mutation in the epidermal growth factor receptor (EGFR) gene or
             anaplastic lymphoma kinase (ALK) fusion oncogene must have received at least 1 and up
             to 2 targeted therapies prior to enrollment.

          -  (Part 2 only) Cohort 2: Have histologically or cytologically confirmed diagnosis of
             nonresectable, recurrent, or metastatic biliary tract carcinoma (intrahepatic or
             extrahepatic cholangiocarcinoma, gallbladder cancer, or ampullary carcinoma) and have
             not received prior systemic anticancer therapy for advanced or metastatic disease.

          -  (Part 2 only) Cohort 3: Have histologically or cytologically confirmed diagnosis of
             metastatic or locally advanced TCC of the urinary tract (bladder, urethra, ureter,
             renal pelvis) (T3b-T4 N0 M0, Tany N1-N3 M0, or Tany Nany M1) and are not candidates
             for surgery.

          -  Have measurable disease per RECIST version 1.1.

          -  Have an ECOG PS of 0 to 1, with the exception of patients in Part 2 (Cohort 3, unfit
             bladder cancer patients) who may have an ECOG PS of 2

          -  Adequate bone marrow reserve, liver and renal function

          -  Have a negative pregnancy test result at Screening for females of childbearing
             potential

          -  Male patients must agree to use a condom during treatment and for 90 days after dosing
             and must agree not to donate sperm for 90 days after dosing

          -  Women of childbearing potential are willing to agree to use 1 of the study defined
             effective methods of birth control from the time of study entry to 6 months after the
             last day of treatment

          -  Reasonably recovered from preceding major surgery as judged by the investigator or no
             major surgery within 4 weeks prior to the start of Day 1 treatment

        Exclusion Criteria:

          -  Have received prior platinum therapy in the past 3 months (Part 1) or 6 months in the
             adjuvant or neoadjuvant setting (Part 2).

          -  Have received prior cisplatin and gemcitabine concomitantly within the last 6 months
             or are refractory to cisplatin and gemcitabine.

          -  Unresolved toxicity from prior radiation, chemotherapy, or other targeted treatment,
             including investigational treatment

          -  Have evidence suggesting pulmonary fibrosis or interstitial pneumonia.

          -  Have a history of thrombocytopenia with complications

          -  Have known hypersensitivity to platinum compounds or gemcitabine.

          -  Have uncontrolled diabetes or have hypertension requiring more than 3 medications for
             control of hypertension.

          -  Have pre-existing alcoholic liver injury or significant liver disease.

          -  Pregnant or breast feeding