This clinical trial is focused on studying the effects of a medication called SAR443122 in adults with moderate to severe ulcerative colitis. Ulcerative colitis is a long-term condition that causes inflammation and sores in the lining of the large intestine. The purpose of the study is to assess how effective and safe different doses of SAR443122 are for treating this condition.

Participants in the study will receive either the medication SAR443122 or a placebo, which looks like the medication but does not contain the active ingredient. The medication is taken orally in the form of a hard capsule. The study will last for up to 52 weeks, during which participants will be monitored to see how well the treatment works and to check for any side effects. The main goal is to see if participants achieve clinical remission, meaning their symptoms improve significantly, by the 12th week of the study.

Throughout the study, various assessments will be conducted to evaluate the participants’ response to the treatment. These assessments include checking for improvements in symptoms, such as stool frequency and rectal bleeding, as well as examining the condition of the colon through endoscopy, a procedure that allows doctors to look inside the colon. The study will also track any adverse events, which are any unwanted effects that occur during the treatment period. The results will help determine the most effective dose of SAR443122 for managing ulcerative colitis.