Gemcitabine Plus Cisplatin With or Without Bintrafusp Alfa (M7824) in Participants With 1L BTC

Inclusion Criteria:

• Are participants with histologically or cytologically confirmed locally advanced ormetastatic BTC
• Participants must have available tumor tissue (primary or metastatic) (archival orfresh biopsies) before the first administration of study treatment
• At least 1 measurable lesion according to RECIST 1.1
• Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 or 1 at studyentry and at Week 1, Day 1 prior to dosing
• Life expectancy of >= 12 weeks, as judged by the Investigator
• Adequate hematological function, hepatic function, renal function, coagulationfunction as defined in the protocol
• Hepatitis B virus (HBV) deoxyribonucleic acid (DNA) positive participants must betreated and on a stable dose of antivirals
• Other protocol defined inclusion criteria could apply

Exclusion Criteria:

• Previous and/or intercurrent cancers
• Receipt of any organ transplantation, including allogeneic stem-cell transplantation,but with the exception of transplants that do not require immunosuppression
• Participants with symptomatic central nervous system (CNS) metastases
• Significant acute or chronic infection including known history of positive test forhuman immunodeficiency virus (HIV), active tuberculosis, uncontrolled biliaryinfection and active bacterial or fungal infection requiring systemic therapy (withthe exception of hepatitis B and hepatitis C) requiring systemic therapy at studyentry and at Week 1 Day 1 prior to dosing.
• Active autoimmune disease that might deteriorate when receiving an immunostimulatoryagent
• History of or concurrent interstitial lung disease
• History of hypersensitivity reactions to bintrafusp alfa, anaphylaxis, or recent (within 5 months) uncontrolled asthma, cardiovascular/cerebrovascular disease
• Chronic obstructive pulmonary disease exacerbation or other respiratory illnessrequiring hospitalization or precluding study therapy within 30 days beforerandomization
• Prior therapy with any antibody/drug targeting T-cell coregulatory proteins (immunecheckpoints)
• Other protocol defined exclusion criteria could apply