OBJECTIVE: Estimate the cost-effectiveness of switching to natalizumab versus fingolimod for patients with highly active RRMS (HA-RRMS) and inadequate response to first-line therapies (BRACETD) from the NHS Scotland perspective using real-world data from MSBase.
BACKGROUND: Some patients with HA-RRMS treated with BRACETD experience disease activity and may benefit from switching to another therapy.
DESIGN/METHODS: A Markov model with health states based on the Expanded Disability Status Scale (EDSS) was developed to capture disability and relapses over time. Treatment-specific annual EDSS transition matrices, annualized relapse rates (ARR) by EDSS, and comparative effectiveness results were obtained from three-way propensity score matched MSBase cohorts (companion abstract submitted at this meeting). Costs and utilities were taken from the United Kingdom (UK) MS Cost of Illness study and standard UK costing sources. Additional clinical data were obtained from publicly available sources. Lifetime clinical and economic outcomes and incremental cost per quality-adjusted life-year (QALY) gained were estimated. Sensitivity analyses estimated the impact of alternative data sources, assumptions, and parameter uncertainty.
RESULTS: MSBase HA-RRMS patients with inadequate response to BRACETD who switched to natalizumab showed a significantly reduced ARR (P<0.001) and increased 6-month confirmed disability improvement likelihood (P<0.001) compared with switching among BRACETD, while the benefit of switching to fingolimod was less marked. In the base-case cost-effectiveness analysis, natalizumab dominated fingolimod, leading to higher QALYs (+0.393) and lower costs (-₤19,148) per patient. Natalizumab remained dominant across scenarios considering a societal perspective, alternative discount rates, 10-year time horizon, and equal treatment discontinuation rates. For fingolimod price discounts ≤23.2%, natalizumab remained dominant; for fingolimod discounts ≤37.6%, natalizumab remained cost-effective at a threshold of ₤30,000/QALY gained.
CONCLUSIONS: Switching to natalizumab dominated switching to fingolimod in patients with HA-RRMS and inadequate response to BRACETD. Natalizumab remained dominant across alternative scenarios and was considered cost-effective with fingolimod price discounts of ≤37.6%.
