ADJUBIL: phase II study of adjuvant immunotherapy with STRIDE regimen with/without capecitabine in biliary tract cancers.

ABSTRACT

Biliary tract cancer is a highly heterogeneous group of gastrointestinal cancers, and the only curative treatment is surgery, which is only applicable at early stages of the malignancy. ADJUBIL, a phase II trial (NCT05239169), aims to evaluate immunotherapy with durvalumab and tremelimumab with or without capecitabine in adjuvant situations for biliary tract cancers. A total of 40 prospective patients will be randomly assigned following surgery, consisting of a two-arm feasibility pilot part with a pick-the-winner design with durvalumab and tremelimumab in combination with or without capecitabine.

This article describes the design of a phase II clinical trial called ADJUBIL, which evaluates the use of immunotherapy (durvalumab and tremelimumab) with or without classic chemotherapy (capecitabine) in biliary tract cancer patients who have undergone curative surgery. This type of treatment is also called adjuvant therapy, meaning it is used after the primary treatment. Biliary tract cancer is a rare type of liver cancer, often diagnosed late. Following surgery, patients may experience an early return of the disease, called tumor relapse. To avoid or delay tumor relapse, patients need extra treatment. Pure chemotherapy (capecitabine) is the standard after curative surgery. For patients with no option for cure, chemotherapy together with new powerful immunotherapy has become standard. This study will recruit 40 adult patients with tumor removal, who will be randomly divided into two groups. Half of them will be treated with immunotherapy only (durvalumab and tremelimumab). The other half will be treated with capecitabine together with immunotherapy. This study will continue for 12 months, but the treatment can be stopped if, for example, the tumor reoccurs or any possible side effect of the therapy is detected. The most effective treatment type will be selected. This type of selection is called pick-the winner.