Pharmacokinetics, Pharmacodynamics, Safety and Tolerability of a New Maintenance Dosing Regimen of Ofatumumab

Inclusion Criteria: * Signed informed consent must be obtained prior to participation in the study. * Male or female study participants aged 18 to 60 years (inclusive) at screening. * Diagnosis of multiple sclerosis (MS) according to the 2017 Revised McDonald criteria (Thompson et al 2018). Relapsing forms of MS: relapsing-remitting MS (RRMS), or active secondary progressive MS (SPMS). Exclusion Criteria: * Participants suspected of not being able or willing to cooperate or comply with study protocol requirements in the opinion of the Investigator or emergence of any clinically significant condition/disease (e.g. active systemic bacterial, viral or fungal infections) during screening prior to Day 1 which might result in safety risk for participants. * Participants with history of confirmed progressive multifocal leukoencephalopathy (PML) or neurological symptoms consistent with PML. * Participants at risk of developing or having reactivation of hepatitis * Emergence of active chronic disease (or stable but treated with immune therapy) prior to Day 1 of the immune system other than MS (e.g. rheumatoid arthritis, scleroderma, Sjögren's syndrome, Crohn's disease, ulcerative colitis, etc.) or with immunodeficiency syndrome (hereditary immune deficiency, drug-induced immune deficiency). * Pregnant or nursing (lactating) women * History of lymphoproliferative disease or any known malignancy or history of malignancy of any organ system (except for basal cell carcinoma, or squamou…