Cost-effectiveness of oral agents in relapsing-remitting multiple sclerosis compared to interferon-based therapy in Saudi Arabia.

Abstract

BACKGROUNDPromising clinical and humanistic outcomes are associated with the use of new oral agents in the treatment of relapsing-remitting multiple sclerosis (RRMS). This is the first cost-effectiveness study comparing these medications in Saudi Arabia.OBJECTIVESWe aimed to compare the cost-effectiveness of fingolimod, teriflunomide, dimethyl fumarate, and interferon (IFN)-β1a products (Avonex and Rebif) as first-line therapies in the treatment of patients with RRMS from a Saudi payer perspective.DESIGNCohort Simulation Model (Markov Model).SETTINGTertiary care hospital.METHODSA hypothetical cohort of 1000 RRMS Saudi patients was assumed to enter a Markov model model with a time horizon of 20 years and an annual cycle length. The model was developed based on an expanded disability status scale (EDSS) to evaluate the cost-effectiveness of the five disease-modifying drugs (DMDs) from a healthcare system perspective. Data on EDSS progression and relapse rates were obtained from the literature; cost data were obtained from King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. Results were expressed as incremental cost-effectiveness ratios (ICERs) and net monetary benefits (NMB) in Saudi Riyals and converted to equivalent $US. The base-case willingness-to-pay (WTP) threshold was assumed to be $100 000 (SAR375 000). One-way sensitivity analysis and probabilistic sensitivity analysis were conducted to test the robustness of the model.MAIN OUTCOME MEASURESICERs and NMB.RESULTSThe base-case analysis results showed Rebif as the optimal therapy at a WTP threshold of $100 000. Avonex had the lowest ICER value of $337 282/QALY when compared to Rebif. One-way sensitivity analysis demonstrated that the results were sensitive to utility weights of health state three and four and the cost of Rebif.CONCLUSIONNone of the DMDs were found to be cost-effective in the treatment of RRMS at a WTP threshold of $100 000 in this analysis. The DMDs would only be cost-effective at a WTP above $300 000.LIMITATIONSThe current analysis did not reflect the Saudi population preference in valuation of health states and did not consider the societal perspective in terms of cost.