Identifying key unmet needs and value drivers in the treatment of focal-onset seizures (FOS) in patients with drug-resistant epilepsy (DRE) in Spain through Multi-Criteria Decision Analysis (MCDA)

Abstract

Introduction: Epilepsy is a serious neurological disease, ranking high in the top causes of disability. Approximately 40% of patients with epilepsy are pharmacoresistant after their seizures failed at least two antiseizure medications (ASMs). Adult patients experiencing focal-onset seizures (FOS) account for approximately 60% of all patients with epilepsy and they are more likely to become drug-resistant epilepsy (DRE) than those with generalized onset. Drug-resistant epilepsy is associated with mortality, morbidity, and reduced quality of life. The information available on the clinical management, health outcomes, and unmet needs of the disease within the Spanish healthcare environment is very limited. Multi-Criteria Decision Analysis (MCDA) allows determination of what represents value in a given indication considering all relevant criteria for healthcare decision-making in a transparent and systematic manner and from the perspective of relevant stakeholders.

Purpose: The aim of this study was to identify the burden of DRE (clinical, quality of life, and economic) and the unmet needs in Spain and to determine what represents value in the treatment of FOS in DRE patients from the perspective of Spanish epileptologists.

Methods: The steps taken to carry out the MCDA were based on previously published good methodological practices. A systematic literature review (combining biomedical databases and gray literature sources) was performed between March and April 2020. Results were reviewed and validated with three epileptologists in June 2020 and used to develop a MCDA value framework, adapted for FOS in DRE, composed of 12 quantitative criteria and 3 contextual criteria. A group of six Spanish epileptologists from four Spanish regions were trained in MCDA methodology before individually validating value criteria (and their definitions based on literature review findings) and assigned relative weights using an ordinal 6-points scale. Results were analyzed and discussed in a group meeting through reflective MCDA discussion methodology.

Results: Drug-resistant epilepsy is considered a very severe health problem with important unmet needs affecting a considerably sized population. While safety and impact on quality of life of available ASMs are considered adequate, efficacy remains insufficient for patients to achieve seizure freedom and maintain it over time. Hence, the therapeutic benefit of pharmacological treatments currently used is regarded as suboptimal. Drug-resistant epilepsy management is associated with moderate pharmacological, relevant direct medical and high indirect costs. Quality of evidence available for current treatments is moderate. It is considered that DRE does not currently stand as a key priority for the Spanish healthcare system.

Conclusions: Drug-resistant epilepsy is considered a very severe health problem associated with relevant unmet needs. These include the lack of availability of specific treatment protocols, the need to improve early diagnosis by increasing the number of referrals to specialized epilepsy units and the availability of specific ASMs with improved efficacy and safety profiles, allowing to reach treatment objectives. Reflective MCDA provided a standardized, transparent approach to evaluate multiple criteria ascertaining what represents value from a holistic point of view and from the perspective of clinical experts, facilitating decision-making.

Keywords: Antiseizure medications; Drug-resistant epilepsy; Epilepsy; Focal-onset seizures; Multi-criteria decision analysis; Spain.