The participant is known to be positive for the human immunodeficiency virus (HIV), hepatitis B surface antigen (HepBsAg), or hepatitis C virus (HCV) ribonucleic acid (RNA). HIV-positive participants on combination antiretroviral therapy are ineligible because of the potential for pharmacokinetic interactions with atezolizumab The participant is known to be positive for the human immunodeficiency virus (HIV), hepatitis B surface antigen (HepBsAg), or hepatitis C (HCV) ribonucleic acid (RNA); HIV-positive participants on combination antiretroviral therapy are ineligible Known to be human immunodeficiency virus (HIV) positive, have hepatitis B surface antigen (HBSAg), or hepatitis C antibodies (HCAb), unless hepatitis C virus ribonucleic acid (HCV RNA) undetected/negative. Known human immunodeficiency virus carrier or a diagnosis of immunodeficiency; any positive test result for hepatitis B virus or hepatitis C virus indicating presence of virus, eg, hepatitis B surface antigen (HBsAg, Australia antigen) positive, or hepatitis C antibody (anti-hepatitis C virus [HCV]) positive (except if HCV-ribonucleic acid [RNA] negative) The subject is known to be positive for hepatitis B surface antigen (HepBsAg), or hepatitis C virus (HCV) ribonucleic acid (RNA) The participant is known to be positive for the human immunodeficiency virus (HIV), hepatitis B surface antigen (HepBsAg), or hepatitis C virus (HCV) ribonucleic acid (RNA); HIV-positive participants on combination antiretroviral therapy are ineligible because of the potential for pharmacokinetic interactions with pembrolizumab The subject is known to be positive for the human immunodeficiency virus (HIV), hepatitis B surface antigen (HepBsAg), or hepatitis C virus (HCV) ribonucleic acid (RNA) Haematological malignancy associated with human immunodeficiency virus (HIV) infection or solid organ transplant or history of known Hepatitis B Antigen or positive Hepatitis C antibody (confirmed by Recombinant ImmunoBlot Assay [RIBA], if available or alternately confirmed by Hepatitis C Virus [HCV] Ribonucleic acid [RNA]). Significant acute or chronic infections including, among others:\r\n* Known history of testing positive for human immunodeficiency virus (HIV), or acquired immunodeficiency syndrome (AIDS).\r\n* Active tuberculosis.\r\n* Positive test for hepatitis B virus (HBV) surface antigen (and/or core antibody) and/or confirmatory hepatitis C virus (HCV) RNA (if anti-HCV antibody tested positive). Significant acute or chronic infections including, among others: a. Known history of testing positive test for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome. b. Active hepatitis B virus (HBV) (HBV surface antigen positive) or hepatitis C virus (HCV) (HCV RNA positive). c. Subjects with known active tuberculosis (history of exposure or history of positive tuberculosis test plus presence of clinical symptoms, physical or radiographic findings). The participant is known to be positive for the human immunodeficiency virus (HIV), hepatitis B surface antigen (HepBsAg), or hepatitis c virus (HCV) ribonucleic acid (RNA); HIV-positive participants on combination antiretroviral therapy are ineligible Known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS). Known history of positive test for hepatitis B virus (HBV) using HBV surface antigen (HBV sAg) test or positive test for hepatitis C virus (HCV) using HCV ribonucleic acid (RNA) or HCV antibody test indicating acute or chronic infection. Ongoing or active systemic infection, known human immunodeficiency virus-ribonucleic acid (RNA) positive, known hepatitis B surface antigen seropositive, or known hepatitis C virus-RNA positive. Significant acute or chronic infections including, among others:\r\n* Known history of testing positive test for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS)\r\n* Positive test for hepatitis B virus (HBV) surface antigen and / or confirmatory hepatitis C virus (HCV) ribonucleic acid (RNA) (if anti-HCV antibody tested positive) Physical and laboratory test findings; a) positive test for hepatitis B virus surface antigen (HBV sAg) or hepatitis C virus ribonucleic acid (RNA) or hepatitis C antibody (HCV antibody) indicating acute or chronic infection; b) known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS) Active infection requiring systemic therapy or significant acute or chronic infections including, among others:\r\n* Hepatitis B virus (HBV) or hepatitis C virus (HCV) infection at screening (positive HBV surface antigen or HCV ribonucleic acid [RNA] if anti-HCV antibody screening test positive)\r\n* Known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome Immunocompromised patients, patients with known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS) and currently receiving antiretroviral therapy, active hepatitis B virus surface antigen (HBV sAg+), active hepatitis C (if antibody [Ab]+ then polymerase chain reaction [PCR]+) indicating acute or chronic infection Significant acute or chronic infections including, among others:\r\n* Known history of testing positive test for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS)\r\n* Positive test for hepatitis B virus (HBV) surface antigen and/or confirmatory hepatitis C virus (HCV) ribonucleic acid (RNA) (if anti-HCV antibody tested positive) Significant acute or chronic infections including, among others:\r\n* Known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS)\r\n* Known history of testing positive for hepatitis B virus (HBV) surface antigen and/or confirmatory hepatitis C virus (HCV) ribonucleic acid (RNA) (if anti-HCV antibody tested positive) Known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS); positive test for hepatitis B virus (HBV) using HBV surface antigen (HBV sAg) test or positive test for hepatitis C virus (HCV) using HCV ribonucleic acid (RNA) or HCV antibody test indicating acute or chronic infection Immunocompromised patients, patients with known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS) and currently receiving antiretroviral therapy, patients with a prior history of known or suspected autoimmune disease, active hepatitis B virus surface antigen (HBV sAg+), active Hepatitis C (if antibody [Ab]+ then polymerase chain reaction [PCR]+) indicating acute or chronic infection, and/or history of interstitial lung disease Patients should be excluded if they have known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS) or if they have a positive test for hepatitis B virus surface antigen (HBV sAg) or hepatitis C virus ribonucleic acid (HCV antibody) indicating acute or chronic infection Patients should be excluded if they have known history of testing positive for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS)\r\n* Patients should be excluded if they have a positive test for hepatitis B virus surface antigen (HBV sAg) or hepatitis C virus ribonucleic acid (HCV antibody) indicating acute or chronic infection Participant is known to be positive for the human immunodeficiency virus (HIV), hepatitis B surface antigen (HepBsAg), or hepatitis C virus (HCV) RNA; HIV-positive participants are ineligible because of the potential for pharmacokinetic interactions of combination antiretroviral therapy with study drugs; in addition, these participants are at increased risk of fatal infections when treated with marrow-suppressive therapy Part A: Known history of testing positive for HIV or known acquired immunodeficiency syndrome (AIDS) or any positive test for hepatitis B virus or hepatitis C virus indicating acute or chronic infection. For Part B, known history of testing positive for HIV or known AIDS in consultation with the Medical Monitor or HBV or HCV infection at screening (positive HBV surface antigen or HCV RNA if anti- HCV antibody screening test positive). Positive for hepatitis B (HBsAg reactive), HCV ribonucleic acid (RNA) qualitative, or human immunodeficiency virus (HIV)( HIV 1/2 antibodies) Participants known to be positive for the human immunodeficiency virus (HIV), hepatitis B antigen (HepBsAg), or hepatitis C virus (HCV) ribonucleic acid (RNA); HIV-positive participants on combination antiretroviral therapy are ineligible Known human immunodeficiency virus (HIV)-positive patients on combination antiretroviral therapy are ineligible; patients who have a positive test for hepatitis B virus surface antigen (HBV sAg) or hepatitis C antibody (hepatitis C virus [HCV] Ab)/ribonucleic acid (HCV RNA) indicating acute or chronic infection are also ineligible (baseline testing required) Significant acute or chronic infections as these may affect the immune response including:\r\n* Known history of testing positive test for human immunodeficiency virus (HIV) or known acquired immunodeficiency syndrome (AIDS)\r\n* Positive test for hepatitis B virus (HBV) surface antigen and / or confirmatory hepatitis C virus (HCV) ribonucleic acid (RNA) (if anti-HCV antibody tested positive) History of chronic hepatitis, Positive test for Hepatitis B virus surface antigen or Hepatitis C antibody (except participants with liver cancer) or Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome(HIV/AIDS)