Natalia Hajduk, Kornelia Tyrakowska, Przemysław Talik

Cannabidiol (CBD) in the Therapy of Dravet and Lennox-Gastaut Syndromes – Efficacy and Safety of Epidyolex

2025-12-05

Research Subject. Drug-resistant epilepsy, which accounts for approximately 30% of epilepsy cases, is one of the greatest challenges facing modern medicine. Of particular importance are its severe forms – Dravet syndrome (DS) and Lennox–Gastaut syndrome (LGS) – characterized by polymorphic seizures, a high relapse rate, and a poor response to conventional pharmacological treatment. Due to the limited effectiveness of current therapies, there is growing interest in alternative treatment methods, including the use of cannabidiol (CBD), a natural compound found in the hemp plant Cannabis sativa L.

Research Objective. The aim of this study was to present the current state of knowledge on the efficacy and safety of cannabidiol in the treatment of epileptic seizures associated with Dravet syndrome and Lennox-Gastaut syndrome and to discuss the pharmacological and economic aspects of Epidyolex – the first registered preparation containing purified CBD.

Materials and Methods. The results of key clinical trials conducted by GW Pharmaceuticals (projects GWPCARE1–5, ClinicalTrials.gov: NCT02091375, NCT02224703, NCT02224573, NCT02224560) were analyzed. Data on the efficacy, safety, pharmacokinetics, and interactions of Epidyolex with other antiepileptic substances were included. Data from the Agency of Health Technology Assessment and Tariff System (Agencji Oceny Technologii Medycznych i Taryfikacji, AOTMiT) and reimbursement decisions of the Ministry of Health were also assessed.

Results. The use of cannabidiol in the form of Epidyolex significantly reduced the number of seizures – by an average of 45–74% in patients with Dravet syndrome and by 48–60% in patients with Lennox–Gastaut syndrome. Adverse reactions included diarrhea, fever, drowsiness, and appetite disturbances, often associated with drug interactions, including those with valproic acid and clobazam. Epidyolex has been recognized by the EMA and the AOTMiT as a medicinal product of high clinical value, and since 2024, it has been reimbursed in Poland under the drug program for patients with DS and LGS.

Conclusions. Cannabidiol, the active ingredient in Epidyolex, represents a significant advance in the treatment of drug-resistant epilepsy, particularly in Dravet and Lennox-Gastaut syndromes. It has proven clinical efficacy, an acceptable safety profile, and the potential for dose reduction of other antiepileptic drugs. Despite the high costs of treatment, the Epidyolex reimbursement allows access to effective therapy for patients with the most severe forms of epilepsy, improving their comfort and quality of life.

Keywords: cannabidiol, Epidyolex, refractory epilepsy, Dravet Syndrome, Lennox-Gastaut syndrome.

© Farm Pol, 2025, 81(4): 245–252