Number needed to treat and associated cost analysis of cenobamate versus third-generation anti-seizure medications for the treatment of focal-onset seizures in patients with drug-resistant epilepsy in Spain.

INTRODUCTION: Epilepsy is a serious neurological disease, ranking high in the top causes of disability. The main goal of its treatment is to achieve seizure freedom without intolerable adverse effects. However, approximately 40% of patients suffer from Drug-Resistant Epilepsy (DRE) despite the availability of the latest options called third-generation Anti-Seizure Medications(ASMs). Cenobamate is the first ASM approved in Spain for the adjunctive treatment of Focal-Onset Seizures (FOS) in adult patients with DRE. The introduction of a new drug increases the number of therapeutic options available, making it important to compare it with existing alternatives in terms of clinical benefit and efficiency. PURPOSE: This study aimed to compare the clinical benefit, in terms of the Number Needed to Treat (NNT), and the efficiency, in terms of Cost per NNT (CNT), associated with cenobamate versus third-generation ASMs used in Spain for the adjunctive treatment of FOS in patients with DRE. METHODS: The Number Needed to Treat data was calculated based on the ≥50% responder rate and seizure freedom endpoints (defined as the percentage of patients achieving 50% and 100% reduction in seizure frequency, respectively), obtained from pivotal clinical trials performed with cenobamate, brivaracetam, perampanel, lacosamide, and eslicarbazepine acetate. The NNT was established as the inverse of the treatment responder rate minus the placebo responder rate and was calculated based on the minimum, mid-range Daily Defined Dose (DDD), and maximum doses studied in the pivotal clinical trials of each ASM. CNT was calculated by multiplying the annual treatment cost by NNT values for each treatment option. RESULTS: In terms of NNT, cenobamate was the ASM associated with the lowest values at all doses for both ≥50% responder rate and seizure freedom compared with the alternatives. In terms of CNT, for ≥50% responder rate, cenobamate was the ASM associated with the lowest CNT values at DDD and lacosamide and eslicarbazepine acetate at the minimum and maximum dose, respectively. For seizure freedom, cenobamate was associated with the lowest CNT value at DDD and the maximum dose and lacosamide at the minimum dose. CONCLUSIONS: Cenobamate could represent the most effective ASM in all doses studied compared to the third-generation ASMs and the most efficient option at DDD for both ≥50% responder rate and seizure freedom. This study could represent an important contribution towards informed decision-making regarding the selection of the most appropriate therapy for FOS in adult patients with DRE from a clinical and economical perspective in Spain.

Determination of the economically justifiable price of cenobamate in the treatment of focal-onset seizures in adult patients with drug-resistant epilepsy in Spain.

OBJECTIVE: To determine the economically justifiable price (EJP) of cenobamate to become a cost-effective alternative compared with third-generation anti-seizure medications in the treatment of focal-onset seizures (FOS) in adult patients with drug-resistant epilepsy (DRE) in Spain. METHODS: Cost-effectiveness analysis compared cenobamate with brivaracetam, perampanel, eslicarbazepine acetate, and lacosamide. Markov model simulation of treatment pathway over a 60-year time horizon is presented. We determined the effectiveness and quality-adjusted life-years (QALYs) of health status and disutilities associated with treatment-related adverse events. Acquisition costs and use of medical resources were obtained from published literature and expert opinion. Base-case of cenobamate's EJP calculated applying a willingness-to-pay (WTP) threshold of €21,000/QALY. Analyses were performed at different thresholds, including dominant price scenario. Result robustness was assessed through sensitivity analyses. RESULTS: Base-case shows that cenobamate's daily EJP of €7.30 is cost-effective for a threshold of €21,000/QALY. At a daily price of €5.45, cenobamate becomes dominant over all treatment alternatives producing cost-savings for the national health system (NHS). Sensitivity analyses supported the robustness of base-case findings. CONCLUSIONS: Treatment with cenobamate produces incremental clinical benefit over third-generation ASMs, and at the base-case, EJP could represent a cost-effective option for the adjunctive treatment of FOS in adult patients with DRE in Spain.