A Study of Diroximel Fumarate (DRF) in Adult Participants From the Asia-Pacific Region With Relapsing Forms of Multiple Sclerosis (RMS)

Key Inclusion Criteria: * Must have a diagnosis of RMS, as defined by revised 2017 McDonald's criteria. * Expanded Disability Status Scale (EDSS) score between 0.0 and 5.0, inclusive, at screening and baseline visit (Day 1). * Neurologically stable with no evidence of relapse within 30 days prior to baseline visit (Day 1). * For Japanese participants: Born in Japan and biological parents and grandparents were of Japanese origin. If previously lived outside of Japan for more than 5 years, must not have had a significantly modified diet since leaving Japan. * For Chinese participants: Born in China, and biological parents and grandparents were of Chinese origin. If previously lived outside of China for more than 5 years, must not have had a significantly modified diet since leaving China. Key Exclusion Criteria: * Has a multiple sclerosis (MS) relapse that has occurred within the 30 days prior to randomization and/or the participant has not stabilized from a previous relapse prior to randomization. * History of severe allergic or anaphylactic reactions or of any allergic reactions that, in the opinion of the investigator, are likely to be exacerbated by any component of the study treatment. * History of, or ongoing, malignant disease, including solid tumors and hematologic malignancies. * Has a history of gastrointestinal (GI) surgery (except appendectomy or cholecystectomy that occurred more than 6 months prior to screening), irritable bowel syndrome, inflammatory bowel dis…