An Active Trend of Immunotherapy Combination Regimen as Second-Line Therapy Towards Advanced Biliary Tract Cancer

As a second-line therapy, oxaliplatin/fluorouracil/leucovorin (FOLFOX) remains the standard of care for patients with biliary tract cancer (BTC); however, its efficacy is suboptimal. The aim of this study was to evaluate whether, compared with chemotherapy alone, the immune checkpoint inhibitor (ICI) combination regimen improved the overall survival (OS) in patients with advanced BTC.

Patients diagnosed with advanced BTC who received chemotherapy or ICI combination therapy as second-line (L2) treatment between January 1, 2018, and April 1, 2022, were retrospectively identified.

A total of 98 patients with BTCs were reviewed and recruited: the chemotherapy group (cohort A, n = 40), the chemotherapy plus ICIs group (cohort B, n = 27), and the tyrosine kinase inhibitor (TKIs) plus ICIs group (cohort C, n = 31). The median progression-free survival (PFS) and median OS were 2.6 months (95% confidence interval [CI]: 1.7-4.2) and 7.8 months (95% CI: 5.9-12.0) for cohort A, 4.3 months (95% CI: 2.9-8.4) and 10.9 months (95% CI: 7.67-NA) for cohort B, 5.1 months (95% CI: 4.0-8.3) and 10.1 months (95% CI: 8.23-NA) for cohort C, respectively. The confirmed overall response rates were 7.5% (3/40, cohort A), 22.2% (6/27, cohort B), and 19.4% (6/31, cohort C), whereas the disease control rates were 47.5% (19/40, cohort A), 77.8% (21/27, cohort B), and 77.4% (24/31, cohort C). Grade 3 or higher treatment-related adverse reaction were reported in 20.0% (cohort A), 37.0% (cohort B), and 41.9% (cohort C) of the patients.

The ICI combination strategy beyond first-line (L1) systemic chemotherapy plays a positive role in advanced BTCs. Both TKIs plus ICIs and chemotherapy plus ICIs could be considered candidates for trials and applied as competitive L2 treatment regimens for advanced BTCs in clinical practice.