Targeting PD-1/PD-L1 in Biliary Tract Cancer: Role and Available Data

There is a critical need for novel therapies to treat patients with advanced biliary tract cancer (BTC). This systematic review summarizes the evidence-based knowledge for the potential role of PD-1 and PD-L1 monoclonal antibodies in the treatment of patients with early-stage and advanced BTC. An Embase database search was conducted, identifying 15 eligible phase II/III clinical trials for review. Results from recent phase III trials show a statistically significant overall survival (OS) benefit from the addition of PD-1/PD-L1 inhibitors to chemotherapy in the first-line management of advanced BTC. Future research should concentrate on the discovery of biomarkers to identify patients who would benefit most from these therapies.The majority of patients with biliary tract cancer (BTC) present with advanced disease (disease that has spread) that cannot be cured. The current mainstay of treatment for advanced BTC is chemotherapy, which aims to prolong life expectancy to just under 12 months. The need for new, more effective treatments for advanced BTC is crucial. This systematic review summarizes the most recent clinical trials that have tested the use of newer drugs called immunotherapy (PD-1 and PD-L1 monoclonal antibodies) in the treatment of both early-stage and advanced BTC. Fifteen clinical trials have been included, each testing different immunotherapy drugs either alone or in combination with other anti-cancer treatments. Promising results from larger trials, have given hope for longer survival in patients with advanced BTC when treated with immunotherapy plus chemotherapy as their first-line treatment after diagnosis. However, further investigation is required to determine whether certain patients might benefit more than others and if immunotherapy drugs can also be given to patients at an earlier or later stage of their disease.