A Study Evaluating the Real World Experience of Participants Treated With BRIUMVI® (Ublituximab-xiiy) for Relapsing Multiple Sclerosis (RMS)

Inclusion Criteria: 1. Confirmed Multiple Sclerosis (MS) diagnosis. 2. Participants who have not received any BRIUMVI® (ublituximab-xiiy) infusion prior to study start. Participants who have been prescribed BRIUMVI® (ublituximab-xiiy) but have not yet received their first infusion on Day 1 of 150 milligrams (mg) can be included. Exclusion Criteria: 1. Have received any live or live-attenuated vaccines (including for varicella-zoster virus or measles) within 4 weeks prior to first BRIUMVI® (ublituximab-xiiy) administration or any non-live vaccines within 2 weeks prior to first BRIUMVI® (ublituximab-xiiy) administration. 2. Any active infection (e.g., active Hepatitis B virus \[HBV\]) 3. Concurrent participation in any interventional MS trials, or planned concurrent treatment with other Multiple Sclerosis Disease Modifying Therapy (MS DMT) during the study period.