A cost-utility analysis of mitoxantrone hydrochloride and interferon beta-1b in the treatment of patients with secondary progressive or progressive relapsing multiple sclerosis.

BACKGROUND: Information on the cost utility of interferon beta-1b and mitoxantrone hydrochloride, 2 disease-modifying agents approved by the US Food and Drug Administration for the treatment of secondary progressive (SP) multiple sclerosis (MS), is limited.
OBJECTIVE: The aim of this study was to compare the cost utility of i.v. mitoxantrone hydrochloride administered every 3 months, s.c. interferon beta-1b administered every other day, and routine supportive care from the perspectives of both the insurer and society.
METHODS: We used a Markov model with health states based on the Kurtzke Expanded Disability Status Scale (EDSS) scores from both an insurer's and a societal perspective (including direct and total costs, respectively). Theoretical patients entered the model with an EDSS score of 3; their progression was followed for 10 years. Transition probabilities were derived from clinical trial data. Cost and utility inputs were taken from the literature. Sensitivity analyses were conducted on all variables.
RESULTS: From the insurer's perspective, the incremental cost-utility ratio of mitoxantrone hydrochloride therapy compared with routine supportive care was 58,272 dollars per quality-adjusted life year (QALY) gained. From a societal perspective, mitoxantrone hydrochloride was more effective and less costly than supportive care. From the perspectives of insurers and society, the cost-utility ratios of interferon beta-1b compared with routine supportive care were 338,738 dollars and 245,700 dollars per QALY gained, respectively. When compared with mitoxantrone hydrochloride, interferon beta-1b had an incremental cost-utility ratio of 741,331 dollars and 658,402 dollars per QALY from the insurer's and society's perspectives, respectively. Cost-utility ratios for mitoxantrone hydrochloride were sensitive to acquisition and administration costs of therapy and to effectiveness at slowing disease progression. Cost-utility ratios for interferon beta-1b were not sensitive to any of the variables included in the model.
CONCLUSIONS: Mitoxantrone hydrochloride is likely to be a cost-effective treatment for patients with SPMS or progressive relapsing MS from an insurer' perspective and is cost saving from a societal perspective. Interferon beta-1b is not likely an efficient treatment using conventional comparisons for cost-effectiveness. This analysis has potentially important implications for policy implementation; however, decisions about which agent to use for each patient should consider the treatment's adverse-event profile, the method of administration, and the patient's preferences for these factors.