OBJECTIVES: Epilepsy is the most common neurological condition worldwide. In Belgium, approximately 47,000 adult epilepsy patients live with focal onset seizures (FOS). Cenobamate is a novel therapy approved for adjunctive treatment of FOS with/without secondary generalization in adult epilepsy patients inadequately controlled despite treatment with ≥2 anti-seizure medications (ASMs). This study assesses the budget impact of providing access to cenobamate as adjunctive treatment for patients inadequately controlled with ≥3 ASMs from Belgian healthcare payer (NIHDI) perspective.

METHODS: The size of the eligible patient population and Belgian clinical practice were estimated from literature and expert opinion. A prevalence-based budget impact model was developed with a 3-year time horizon. The model accounts for the eligible population, projected market shares, drug acquisition costs and medical costs (monitoring, treatment of seizures and adverse events (AEs)). Efficacy, AE rates, treatment schedules/dosing were obtained from publications or Product Characteristics (SmPCs). Costs were obtained from national databases, literature and expert opinion.

RESULTS: The estimated eligible population for the treatment of FOS in epilepsy with a 3^rd generation ASM is around 8,600 patients yearly, of which 517 to 1,742 patients were estimated to be treated with cenobamate, in year 1 to 3 respectively. Although cenobamate adds 6,552,486 EUR on the drug budget, the reduction due to replacement of other ASMs over the three-year period, yields a total additional impact on the drug budget of 1,062,940 EUR. Additionally, the efficacy of cenobamate leads to significant higher response and seizure reduction, resulting in a saving of €13,949,412 mainly associated to medical costs for the treatment of seizures (consultations, ER visits and hospitalization). Sensitivity analyses confirm the robustness of the model and associated results.

CONCLUSIONS: Savings generated at medical cost level offset the impact of cenobamate on the drug budget, resulting in an overall healthcare budget saving of €12,886,471 for NIHDI.