This clinical trial is focused on studying a condition called Primary Sclerosing Cholangitis (PSC), which is a disease that affects the bile ducts in the liver and can cause itching, known as pruritus. The study is testing a new treatment called volixibat, which is taken as a hard capsule by mouth. Volixibat is an investigational drug, meaning it is still being studied and is not yet approved for general use. It works as an ileal bile acid transporter inhibitor, which means it helps to reduce the amount of bile acid in the body, potentially easing the itching associated with PSC.

The purpose of the study is to evaluate how effective and safe volixibat is compared to a placebo in treating the itching caused by PSC. Participants in the study will be randomly assigned to receive either volixibat or a placebo, and neither the participants nor the researchers will know who is receiving which treatment. This is known as a double-blind study. The study will last for a period of time, during which participants will take the medication and attend regular study visits to monitor their condition and any changes in their symptoms.

Throughout the study, the main focus will be on observing changes in the severity of itching using a tool called the Adult ItchRO. This tool helps to measure how the itching affects daily life. The study aims to provide valuable information on whether volixibat can effectively reduce itching in people with PSC, potentially leading to a new treatment option for this challenging condition.