Eligibility Details:  
        Inclusion Criteria:
          -  Dose escalation participants: Has any histologically- or cytologically-confirmed
             advanced/metastatic solid tumor by pathology report and has received, has been
             intolerant to, or has been ineligible for all treatment known to confer clinical
             benefit. Solid tumors of any type are eligible for enrollment.
          -  Has measurable disease by Response Evaluation Criteria In Solid Tumors version 1.1
             (RECIST 1.1) as assessed by the local site investigator/radiology.
          -  Submits an evaluable baseline tumor sample for analysis (either a recent or archival
             tumor sample).
          -  Dose Escalation Part C and Back-fill participants: Has 1 or more discrete malignant
             lesions that are amenable to biopsy
          -  Has a performance status of 0 or 1 on the Eastern Cooperative Oncology Group (ECOG)
             Performance Scale.
          -  Demonstrates adequate organ function
          -  A male participant must agree to use an approved contraception(s) during the treatment
             period and for at least 180 days after the last dose of study treatment and refrain
             from donating sperm during this period.
          -  A female participant is eligible to participate if she is not pregnant, not
             breastfeeding, and either not a woman of childbearing potential (WOCBP) OR if a WOCBP
             agrees to follow the study contraceptive guidance during the treatment period and for
             at least 120 days after the last dose of study treatment.
          -  Expansion phase Arm A participants:
               -  Has histologically or cytologically confirmed metastatic pancreatic
                  adenocarcinoma.
               -  Received at least 1 prior line of therapy and no more than 3 prior lines of
                  systemic therapy.
          -  Expansion phase Arm B participants:
               -  Has histologically or cytologically confirmed pleural or peritoneal malignant
                  mesothelioma, epithelial, sarcomatoid, or biphasic subtypes.
               -  Has disease progression on or after pemetrexed and cis- or carboplatin.
          -  Expansion phase Arm C participants:
               -  Has histologically confirmed recurrent or metastatic head and neck squamous cell
                  cancer (HNSCC) of the oral cavity, oropharynx, hypopharynx, and/or larynx that is
                  considered incurable by local therapies.
               -  Has experienced disease progression at any time during or after treatment with a
                  platinum-containing (eg, carboplatin or cisplatin) regimen with or without
                  cetuximab.
          -  Expansion phase Arm D participants:
               -  Has histologically confirmed advanced or metastatic HNSCC of the oral cavity,
                  oropharynx, hypopharynx, and/or larynx that is considered incurable by local
                  therapies.
               -  Should not have had any prior PD-1/PD-L1 therapy.
          -  Expansion phase Arms E and F participants:
               -  Has a histologically or cytologically confirmed diagnosis of Advanced (Stage
                  IIIb) or Stage IV metastatic non-small-cell lung cancer (NSCLC).
               -  Has received no prior systemic therapy for advanced NSCLC.
               -  Has archival or fresh tissue available for central PD-L1 testing prior to
                  randomization.
          -  Expansion phase Arm G participants:
               -  Has a histologically or cytologically confirmed diagnosis of Advanced (Stage
                  IIIb) or Stage IV metastatic non-squamous NSCLC (AJCC version 8).
               -  Is able to tolerate chemotherapy with carboplatin and pemetrexed.
          -  Expansion phase Arm H participants:
               -  Has histologically confirmed diagnosis of renal cell cancer (RCC) with clear cell
                  component with or without sarcomatoid features.
               -  Has locally advanced/metastatic disease or has recurrent disease.
               -  Has received no prior systemic therapy for advanced RCC.
        Exclusion Criteria:
          -  Has had chemotherapy, definitive radiation, or biological cancer therapy within 4
             weeks (2 weeks for palliative radiation) prior to the first dose of study therapy, or
             has not recovered from any AEs that were due to cancer therapeutics administered more
             than 4 weeks earlier.
          -  Has not recovered from all radiation-related toxicities to Grade 1 or less, requires
             corticosteroids, and had radiation pneumonitis.
          -  Has a history of a second malignancy, unless potentially curative treatment has been
             completed with no evidence of malignancy for 2 years.
          -  Has known untreated central nervous system metastases or known carcinomatous
             meningitis.
          -  Has received any prior immunotherapy and was discontinued from that treatment due to a
             Grade 3 or higher residual immune-related AEs
          -  Previously had a severe hypersensitivity reaction to treatment with a monoclonal
             antibody or has a known sensitivity to any component of pembrolizumab.
          -  Has an active infection requiring therapy.
          -  Has a history of interstitial lung disease.
          -  Has a history of noninfectious pneumonitis that required steroids or current
             pneumonitis.
          -  Has an active autoimmune disease that has required systemic treatment in the past 2
             years except vitiligo or resolved childhood asthma/atopy.
          -  Has clinically significant cardiac disease, including unstable angina, acute
             myocardial infarction within 6 months from Day 1 of study drug administration, or New
             York Heart Association Class III or IV congestive heart failure.
          -  Known history of human immunodeficiency virus (HIV).
          -  Known active hepatitis B or C.
          -  Is taking chronic systemic steroids in doses >10 mg daily of prednisone or equivalent
             within 7 days prior to the first dose of trial treatment.
          -  Has not fully recovered from any effects of major surgery without significant
             detectable infection. Surgeries that required general anesthesia must be completed at
             least 2 weeks before first study treatment administration. Surgery requiring
             regional/epidural anesthesia must be completed at least 72 hours before first study
             treatment administration and participants should be recovered.
          -  Has received a live virus vaccine within 30 days of planned treatment start.
          -  Is currently participating and receiving study therapy in a study of an
             investigational agent or ha participated and received study therapy in a study of an
             investigational agent or has used an investigational device within 28 days of
             administration of MK-4830.
          -  Expansion phase Arm A participants:
               -  Has received more than 3 lines of prior therapy for advanced disease (pancreatic
                  cancer).
          -  Expansion phase Arm B participants:
               -  Has had more than 2 prior lines of cytotoxic therapy.
          -  Expansion phase Arm E, F, and G participants:
               -  Has received prior systemic chemotherapy or other targeted or biological
                  antineoplastic therapy treatment for their Stage IIIb or Stage IV metastatic
                  (Arms E and F)/non-squamous (Arm G) NSCLC.
               -  Has had prior treatment with any anti-PD-1, PD-L1, or programmed cell
                  death-ligand 2 (PD-L2) agent.
          -  Expansion phase Arm H participants:
               -  Has had prior treatment with any anti-PD-1, PD-L1, or PD-L2 agent or an antibody
                  targeting any other immune-regulatory receptors or mechanisms.
               -  Has received prior systemic anti-cancer therapy for RCC completed within 12
                  months prior to randomization.
               -  Has a clinically significant gastrointestinal (GI) abnormality.
               -  Has a history of deep vein thrombosis or pulmonary embolism within 6 months prior
                  to screening.
               -  Has poorly controlled hypertension.
               -  Has active GI bleeding.
               -  Has evidence of inadequate wound healing.
               -  Has active bleeding disorder or other history of significant bleeding episodes
                  within 30 days prior to randomization.
               -  Has hemoptysis within 6 weeks prior to randomization.