Objective: To perform a cost-effectiveness analysis of three immunomodulatory treatments for newly diagnosed nonprimary progressive MS: interferon beta-1a, interferon beta-1b, and glatiramer acetate.
Methods: We developed a state-transition model to estimate the health effects and costs associated with interferon beta-1a, interferon beta-1b, glatiramer acetate, and no treatment for hypothetical cohorts of men and women with non-primary progressive MS. We used the Expanded Disability Status Scale as the measure of disability and included both relapses and disease progression in the model. We evaluated treatment strategies assuming a 10-year treatment duration using the societal perspective. We elicited preferences for disability and treatment states using standard-gamble questions and modeled the disutility associated with treatment administration and side effects explicitly. Main outcome measures were net gains in quality-adjusted life expectancy and incremental cost-effectiveness ratios in dollars per quality-adjusted life year (QALY) gained.
Results: For treatment duration of 10 years for newly diagnosed non-primary progressive MS, interferon beta-1a yielded the largest gain in quality-adjusted life expectancy with an incremental cost-effectiveness ratio of $2,200,000/QALY for women and $1,800,000/QALY for men, compared with no treatment. For a 5-year treatment duration, a "no treatment" strategy yielded more quality-adjusted life years than any of the treatment strategies. Cost-effectiveness ratios were similar for all three immunomodulatory treatments evaluated.
Conclusions: Cost-effectiveness results for all three immunomodulatory treatments for MS were unfavorable in the simulated study population under a wide range of assumptions. For treatment duration less than or equal to 5 years, expected benefits of treatment may not outweigh disutility associated with side effects and treatment discomfort.