A Study to Assess How Well and Safely Elafibranor Works in Adult Participants With Primary Sclerosing Cholangitis

The purpose of this study is to find out how well and safely elafibranor works compared to placebo in adult participants with Primary sclerosing cholangitis (PSC). PSC is a rare disease that causes inflammation and scarring of the bile ducts in the liver. Over time, this can lead to liver damage and serious health problems, including the need for a liver transplant and death. In this study, about 350 participants with large duct PSC will take part. Participants will be randomized to receive either elafibranor 120 mg once daily or a placebo (a tablet with no active medicine). The study includes a screening period, an treatment period, and a post-treatment safety follow-up. During the study, participants will undergo routine clinical assessments, laboratory testing, imaging evaluations, and complete patient-reassessments to evaluate liver disease progression, symptoms, quality of life and safety. Following the end of treatment, participants will complete a safety follow-up period at approximately four weeks. Participants may withdraw from the study at any time. Each participant may be in the study for several years, as the treatment period will continue until the study reaches enough health events among participants, which is expected to take about 5 years.