A Single Arm Study Evaluating the Efficacy, Safety and Tolerability of Ofatumumab in Patients With Relapsing Multiple Sclerosis

This was a single-arm, multicenter, prospective, study in participants with relapsing multiple sclerosis (MS) who had been previously treated with intravenous (i.v.) anti-CD20 monoclonal antibody (aCD20 mAb) therapy and had received at least 2 consecutive courses of intravenously administered ocrelizumab or rituximab every 6 months, and the last dose was within 4 to 9 months before Baseline/Day 1. In this study, participants could have enrolled only if discontinuing i.v. aCD20 mAb therapy for reasons other than lack of efficacy or due to certain treatment-emergent adverse events (TEAEs). Reasons for switching could have included but were not limited to physician/participant preference, access to commercial drug (e.g. insurance coverage issues), or for other logistical reasons (e.g. geographical relocation, travel, etc.). Eligible participants received open label ofatumumab 20 mg subcutaneous (s.c.) once monthly for 12 months following initial loading regimen of 20 mg s.c. doses on Days 1, 7, and 14. After the 12-Month Treatment Period there was a Telephone Safety Follow-up call 30 days after last dose of study treatment. The Core phase covered a 28-day Screening Period, 12-Month Treatment Period, and 30-Day Telephone Safety Follow-up. Upon completing the study, participants could opt to continue ofatumumab therapy through commercial services. Participants who did not continue into the ofatumumab commercial patient services hub within 1 month of the end of study visit or who did not switch to another therapy had to continue into the Post-Treatment Safety Follow-up period, consisting of every 3 month visits including B cell monitoring, until they were able to start on commercial ofatumumab, until they switched to another therapy, or until their B cells were repleted (defined as a B cell concentration greater than the individual participant's baseline value prior to starting the i.v. aCD20 mAb or greater than the lower limit of normal).