TAS-102 in Treating Advanced Biliary Tract Cancers

PRIMARY OBJECTIVES: I. Determine the efficacy of trifluridine/tipiracil hydrochloride combination agent TAS-102 (FTD/TPI \[TAS-102\]) in patients with refractory cholangiocarcinoma using progression-free survival at 16 weeks. SECONDARY OBJECTIVES: I. Assess the safety and tolerability of FTD/TPI (TAS-102) in patients with refractory cholangiocarcinoma through adverse event monitoring. II. Further explore the efficacy of FTD/TPI (TAS-102) in patients with refractory cholangiocarcinoma by overall response rates, progression-free survival, and overall survival. TERTIARY OBJECTIVES: I. Determine if circulating tumor cells (CTCs) or cell-free deoxyribonucleic acid (DNA) (cfDNA) at baseline correlates with prognosis or response to therapy. II. Determine if change in CTCs or cfDNA correlates with efficacy endpoints. III. Determine if different mutational status of the tumor will affect efficacy endpoints. OUTLINE: Patients receive trifluridine/tipiracil hydrochloride combination agent TAS-102 orally (PO) twice daily (BID) on days 1-5 and 8-12. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 30 days and then every 3 months for up to 2 years.