Exit Strategies in Patients With Stable MS: Cost-Effectiveness of Extended Interval Dosing of Ocrelizumab and Natalizumab vs. De-escalating to Cladribine
Author(s)
Matthijs M. Versteegh, BSc, MA, PhD1, Simone A. Huygens, Bsc, MSc, PhD2.
1Huygens & Versteegh B.V., Zwijndrecht, Netherlands, 2Huygens & Versteegh B.V., Zwijdrecht, Netherlands.
1Huygens & Versteegh B.V., Zwijndrecht, Netherlands, 2Huygens & Versteegh B.V., Zwijdrecht, Netherlands.
OBJECTIVES: Long-term treatment may expose MS patients to risks such as increased infection rates due to the decline in patients' immune systems. Stopping treatment may expose patients to risk of disease progression. Alternatives to stopping disease modifying therapies (DMTs) are ‘exit strategies’, such as extended interval dosing (EID) or de-escalating infection risks by switching to other DMTs. This study compares the cost-effectiveness of several exit strategies for MS patients who are stable on second line ocrelizumab or natalizumab.
METHODS: We updated a previously published treatment sequence model to include time-dependent transition probabilities for EDSS progression. This model identified differences in costs and quality adjusted life years (QALYs) between exit strategies for patients with stable MS: continue as is, increase the dosing interval of ocrelizumab or natalizumab, or switch to cladribine. We analysed uncertainty around these differences using probabilistic sensitivity analyses. We applied a societal perspective with a lifetime time horizon and discount rates for costs and QALYs of 3.0% and 1.5%, respectively. The threshold for being cost-effective was €50,000 per QALY.
RESULTS: Over two thirds of patients who received second line treatment fulfilled the criteria to enter an exit strategy. Exit strategies were more than 90% likely to be cost-effective relative to no exit strategies. Among exit strategies, de-escalation to cladribine was more than 90% likely to be cost-effective relative to EID of ocrelizumab or natalizumab.
CONCLUSIONS: Adopting an exit strategy for patients who are stable on ocrelizumab or natalizumab is a cost-effective alternative to continuing treatment or extended-interval-dosing. Among exit strategies de-escalating to cladribine is the most cost-effective option. These results demonstrate the relevance of clinical studies into extended interval dosing or de-escalation switches which may test the hypothesis of the benefit of exit strategies demonstrated in this simulation study.
METHODS: We updated a previously published treatment sequence model to include time-dependent transition probabilities for EDSS progression. This model identified differences in costs and quality adjusted life years (QALYs) between exit strategies for patients with stable MS: continue as is, increase the dosing interval of ocrelizumab or natalizumab, or switch to cladribine. We analysed uncertainty around these differences using probabilistic sensitivity analyses. We applied a societal perspective with a lifetime time horizon and discount rates for costs and QALYs of 3.0% and 1.5%, respectively. The threshold for being cost-effective was €50,000 per QALY.
RESULTS: Over two thirds of patients who received second line treatment fulfilled the criteria to enter an exit strategy. Exit strategies were more than 90% likely to be cost-effective relative to no exit strategies. Among exit strategies, de-escalation to cladribine was more than 90% likely to be cost-effective relative to EID of ocrelizumab or natalizumab.
CONCLUSIONS: Adopting an exit strategy for patients who are stable on ocrelizumab or natalizumab is a cost-effective alternative to continuing treatment or extended-interval-dosing. Among exit strategies de-escalating to cladribine is the most cost-effective option. These results demonstrate the relevance of clinical studies into extended interval dosing or de-escalation switches which may test the hypothesis of the benefit of exit strategies demonstrated in this simulation study.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
EE452
Topic
Clinical Outcomes, Economic Evaluation, Health Technology Assessment
Disease
Neurological Disorders, No Additional Disease & Conditions/Specialized Treatment Areas