To assess the cost-effectiveness of delayed-release dimethyl fumarate (DMF, also known as gastro-resistant DMF), an effective therapy for relapsing forms of multiple sclerosis (MS), compared with glatiramer acetate and fingolimod, commonly used treatments in the US.
A Markov model was developed comparing delayed-release DMF to glatiramer acetate and fingolimod using a US payer perspective and 20-year time horizon. A cohort of patients, mean age 38 years, with relapsing-remitting MS and Kurtzke Expanded Disability Status Scale (EDSS) scores between 0-6 entered the model. Efficacy and safety were estimated by mixed-treatment comparison of data from the DEFINE and CONFIRM trials and clinical trials of other disease-modifying therapies. Data from published studies were used to derive resource use, cost, and utility inputs. Key outcomes included costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. Alternative scenarios tested in a sensitivity analysis included drug efficacy, EDSS-related or relapse-related costs, alternative perspectives, drug acquisition costs, and utility.
Base-case results with a 20-year time horizon indicated that delayed-release DMF increased QALYs +0.450 or +0.359 compared with glatiramer acetate or fingolimod, respectively. Reductions in 20-year costs with delayed-release DMF were -$70,644 compared with once-daily glatiramer acetate and -$32,958 compared with fingolimod. In an analysis comparing delayed-release DMF to three-times-weekly glatiramer acetate and assuming similar efficacy and safety to the once-daily formulation, 20-year costs with delayed-release DMF were increased by $15,806 and cost per QALY gained was $35,142. The differences in costs were most sensitive to acquisition cost and inclusion of informal care costs and productivity losses. The differences in QALYs were most sensitive to the impact of delayed-release DMF on disease progression and the EDSS utility weights.
Delayed-release DMF is likely to increase QALYs for patients with relapsing forms of MS and be cost-effective compared with fingolimod and glatiramer acetate.