This clinical trial is focused on studying the effects of a new treatment for Multiple Sclerosis (MS), a condition that affects the brain and spinal cord, leading to a range of symptoms such as fatigue, difficulty walking, and vision problems. The study compares the effectiveness and safety of a medication called remibrutinib with another medication known as teriflunomide. Remibrutinib is a new drug that works by targeting specific proteins in the body to reduce inflammation, while teriflunomide is an existing treatment that helps to modulate the immune system and reduce inflammation.

The purpose of this study is to determine if remibrutinib is more effective than teriflunomide in reducing the frequency of relapses in people with relapsing forms of MS. Participants in the study will be randomly assigned to receive either remibrutinib, teriflunomide, or a placebo, which is a substance with no active medication. The study will begin with a period where participants receive either remibrutinib or teriflunomide, followed by an extended treatment phase where all participants will receive remibrutinib. This approach helps researchers understand the long-term effects of remibrutinib on MS.

Throughout the study, participants will take the medications orally, and their health will be monitored regularly to assess the impact of the treatments. The study aims to provide valuable information on how well remibrutinib works compared to teriflunomide and to ensure the safety of participants. By participating in this study, researchers hope to find a more effective treatment option for those living with relapsing MS.