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PharmacoEconomics

, Volume 36, Issue 10, pp 1253–1261 | Cite as

Economic Evaluation of Stiripentol for Dravet Syndrome: A Cost-Utility Analysis

  • Jesse ElliottEmail author
  • Bláthnaid McCoy
  • Tammy Clifford
  • George A. Wells
  • Doug Coyle
Original Research Article

Abstract

Background

Dravet syndrome is a catastrophic form of pediatric treatment-resistant epilepsy with few effective treatment options. Stiripentol is approved for use in Canada for treatment of Dravet syndrome, but the associated long-term costs and benefits have not been well-studied and its cost effectiveness is unclear.

Objective

The aim of this study was to evaluate the cost effectiveness of stiripentol as an adjunctive treatment to clobazam and valproate for treatment of Dravet syndrome from the perspective of the Canadian public healthcare payer.

Methods

A cost-utility analysis was performed to estimate the costs and quality-adjusted life-years (QALYs) associated with adjunctive stiripentol treatment compared with clobazam and valproate alone in children with Dravet syndrome. Transition probabilities, drug efficacy, utility weights, and costs were obtained from a review of the literature. Probabilistic analyses were conducted using a Markov model with health states related to seizure frequency. A 10-year horizon was used. The incremental cost per QALY gained (incremental cost-effectiveness ratio [ICER]) for adjunctive use of stiripentol was calculated, and assumptions were explored in scenario analyses. All costs are expressed in 2017 Canadian dollars ($Can).

Results

Compared with clobazam and valproate alone, the adjunctive use of stiripentol is associated with an ICER of $Can151,310. At a willingness-to-pay threshold of $Can50,000, the probability that stiripentol was the optimal treatment was 5.2%. The cost of stiripentol would need to be reduced by 61.4% for stiripentol to be cost effective.

Conclusion

From the perspective of the Canadian public healthcare payer, stiripentol is not cost effective at its current price at a willingness-to-pay threshold of $Can50,000. Funding stiripentol will be associated with important opportunity costs that bear consideration.

Notes

Acknowledgements

JE is supported by an Ontario Graduate Scholarship and is a trainee in the Drug Safety and Effectiveness Cross-Disciplinary Training (DSECT) program, funded by the Canadian Institutes of Health Research.

Author contributions

All of the authors contributed to the conception and planning of the study, the analysis and/or interpretation of the data; drafting and critical revision of the manuscript; and approved the version of the manuscript submitted for publication.

Compliance with Ethical Standards

Funding

No specific funding was received for this study.

Conflict of interest

Bláthnaid McCoy is principal investigator in a study of cannabinoids for Dravet syndrome. Tammy Clifford is employed by CADTH (Canadian Agency for Drugs and Technologies in Health). She had no role in the review of stiripentol that was undertaken by the Common Drug Review. Jesse Elliott, George Wells, and Doug Coyle have no conflicts of interest to declare.

Data availability statement

All data generated or analyzed during this study are included in this published article (and its online supplementary information files). The Markov model used in this analysis was provided for peer review.

Supplementary material

40273_2018_669_MOESM1_ESM.pdf (516 kb)
Supplementary material 1 (PDF 515 kb)
40273_2018_669_MOESM2_ESM.docx (33 kb)
Supplementary material 2 (DOCX 33 kb)

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Epidemiology and Public HealthUniversity of OttawaOttawaCanada
  2. 2.Department of PaediatricsUniversity of TorontoTorontoCanada
  3. 3.Division of NeurologyThe Hospital for Sick ChildrenTorontoCanada
  4. 4.CADTHOttawaCanada
  5. 5.Cardiovascular Research Methods CentreUniversity of Ottawa Heart InstituteOttawaCanada

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