BackgroundOfatumumab is a high-efficacy disease-modifying therapy (DMT) approved for first-line treatment of relapsing-remitting multiple sclerosis (RRMS) in Canada.ObjectiveThe aim of this study was to evaluate the cost effectiveness of ofatumumab from a Canadian healthcare system perspective.MethodsA Markov cohort model was run over 65 years using annual cycles, 1.5% annual discount rate, and 100% treatment discontinuation at 10 years. The British Columbia database informed natural history transition probabilities. Treatment efficacy for DMTs were sourced from a network meta-analysis. Clinical trial data were used to estimate probabilities for treatment-related adverse events. Health utilities and costs were obtained from Canadian sources (if available) and the literature.ResultsAmong first-line indicated therapies for RRMS, ofatumumab was dominant (more effective, lower costs) over teriflunomide, interferons, dimethyl fumarate, and ocrelizumab. Compared with glatiramer acetate and best supportive care, ofatumumab resulted in incremental cost-effectiveness ratios (ICERs) of $24,189 Canadian dollars per quality-adjusted life-year (QALY) and $28,014/QALY, respectively. At a willingness-to-pay threshold of $50,000/QALY, ofatumumab had a 64.3% probability of being cost effective. Among second-line therapies (scenario analysis), ofatumumab dominated natalizumab and fingolimod and resulted in an ICER of $50,969 versus cladribine.ConclusionsOfatumumab is cost effective against all comparators and dominant against all currently approved and reimbursed first-line DMTs for RRMS, except glatiramer acetate.Supplementary InformationThe online version contains supplementary material available at 10.1007/s41669-022-00363-1.