OBJECTIVES: : Multiple sclerosis (MS) is a neurodegenerative and demyelinating disease of the central nervous system leading to impaired nerve impulse conduction with concomitant symptoms such as weakness in limbs, muscle stiffness or spasms, paralysis, problems with vision, fatigue and cognitive changes. Current disease modifying therapies indicated for first-line treatment of relapsing-remitting MS (RRMS) in Sweden are injection therapies including beta interferons and glatiramer acetate, and the two recently approved oral treatments delayed-relase dimethyl fumarate (DMF; also known as gastro-resistant DMF) and teriflunomide. The objective of the present study was to evaluate the cost-effectiveness of DMF (versus the least costly first-line alternative interferon beta-1b  METHODS: The analyses were performed in a Markov model with health states describing the management and consequences of RRMS in terms of relapses and progression through a series of disability states, based upon the Kurtzke Expanded Disability Status Scale (EDSS). The societal and the payer perspectives for a time horizon of 30 years were applied for the base-case analyses.  RESULTS: : The results from the societal as well as the payer perspective showed that DMF was dominant as compared to interferon beta for the treatment of RRMS in Sweden, offering cost-savings and QALY gain of 0.476. One-way sensitivity analyses (±25% of base-case) showed that DMF remained dominant in all variations tested with the exception of the treatment effect on disability progression rate. Probabilistic sensitivity analyses from the societal perspective showed that DMF was dominant in 61% of the simulations.  CONCLUSIONS: In the present analyses DMF dominated interferon beta-1b from the societal as well as payer perspective, but showed sensitivity to variations in the variable treatment effect on disease progression. This study was sponsored by Biogen.