Current state, challenges, unmet needs, and future directions in the pharmacological treatment of biliary tract cancer

INTRODUCTION: There has been a significant change in the treatment paradigm of biliary tract cancers (BTCs) in recent years with the introduction of chemoimmunotherapy and the development of targeted agents. In the present review, we describe the current landscape of systemic therapy for BTC and discuss forthcoming novel therapeutics. AREAS COVERED: We completed a narrative review using pertinent clinical trials discussing systemic therapy for BTC listed on PubMed, as well as ongoing trials included on clinicaltrials.gov. We discuss evidence for use of systemic therapy in the adjuvant setting and review first- and second-line systemic therapy, including targeted agents, for treatment of advanced BTC. EXPERT OPINION: Despite advances in systemic therapy for BTC, there is a high incidence of recurrence for resected diseases and the prognosis for metastatic diseases remains poor. Development and assessment of novel therapeutics will be essential going forward, as will research regarding means to overcome resistance mechanisms that limit efficacy of targeted agents.