Expanding the therapeutic role of highly purified cannabidiol in monogenic epilepsies: A multicenter real-world study.

OBJECTIVE

This real-world, retrospective, multicenter study aims to investigate the effectiveness of highly purified cannabidiol (CBD) in a large cohort of patients with epilepsy of genetic etiology due to an identified monogenic cause. Additionally, we examine the potential relationship between specific genetic subgroups and treatment response.

METHODS

This study was conducted across 27 epilepsy centers and included patients with monogenic epileptic disorders (pathogenic or likely pathogenic variants) who were treated with highly purified CBD for at least 3 months.

RESULTS

A total of 266 patients (135 females, 50.8%) with monogenic epilepsies were included with a median age at CBD initiation of 12 years (interquartile range [IQR] = 7-19) and a median follow-up duration of 17 months (IQR = 12-24). Overall, 77 different monogenic epilepsies have been included, with the most common genes being SCN1A (32.3%), TSC2 (13.5%), CDKL5, and MECP2 (4.5% each). The mean seizure reduction at the last follow-up was 38.6%, with 47.5% of patients achieving ≥50% seizure reduction and 7.4% achieving seizure freedom. The Clinical Global Impression scale indicated improvement in 65.8% of patients. The general linear mixed model revealed that a shorter maximum duration of seizure freedom before CBD initiation and a higher degree of intellectual disability were independently associated with lower CBD effectiveness. Conversely, no significant differences in seizure outcome were observed across different epilepsy syndromes (Lennox-Gastaut syndrome, Dravet syndrome, tuberous sclerosis complex epilepsy, and other developmental and epileptic encephalopathy), between approved indications and off-label use, or between concomitant clobazam use or not.

SIGNIFICANCE: This study supports CBD as a potential treatment for monogenic epilepsies beyond its licensed indications, demonstrating comparable effectiveness between approved and off-label use and suggesting genetic subgroups with promising treatment responses.