Rilvegostomig + Chemotherapy as Adjuvant Therapy for Biliary Tract Cancer After Resection (ARTEMIDE-Biliary01)

This study is for adults aged 18 or older who have recently had surgery to remove their bile duct cancer. Crucially, the surgery must have aimed to remove all the cancer visible, and imaging tests must show that there is no active cancer remaining in your body before you start the trial. You must also be well enough to take part in daily activities without significant difficulty.

To be considered, doctors will need a sample of your tumour from your surgery. You also need to be able to start the study within 12 weeks of your operation, making sure your surgical wounds have healed well. Your doctor will assess specific details about your cancer to make sure it's the right type for this study.

There are also some reasons why you wouldn't be able to join. For example, if your cancer had already spread or was too advanced to be removed by surgery at your diagnosis. You also wouldn't be able to join if you have certain other serious medical conditions, such as some autoimmune diseases, or if you've had a blood clot in the past 3 months. Previous anti-cancer treatments for bile duct cancer *before* your surgery would also make you ineligible.

If you join this study, you will be assigned to one of two groups by chance (like flipping a coin). One group will receive the new medicine, rilvegostomig, along with chemotherapy, and the other group will receive a dummy pill (placebo) with chemotherapy. You and your doctor won't know which group you are in. You will receive regular doses of your assigned medicine and chemotherapy, which will be decided by your study doctor based on standard choices like capecitabine, S-1, or gemcitabine/cisplatin.

Throughout the study, you'll have regular visits to the hospital for checks. These visits will involve blood tests, physical examinations, and scans (like CT or MRI) to see how you're responding and to check for any side effects. These checks are important to keep you safe and to understand how the medicine is working. The total time you participate in and are followed up by the study will be several years, even after you finish taking the medicines, so doctors can see the long-term effects.