Efficacy and safety of cannabidiol in children with developmental and epileptic encephalopathies: A systematic review.

Background: Developmental and epileptic encephalopathies (DEEs) constitute rare epileptic conditions characterized by treatment-resistant seizures, neurodevelopmental delay, and various comorbidities. None of the currently available drugs have proven effective in suppressing epileptiform activity in those conditions. Objectives: We aimed to assess the efficacy and safety of cannabidiol in children with DEEs through a systematic review. Methods: We searched MEDLINE, Cochrane Central Register of Controlled Trials, trial registries, and reference lists of included studies. We conducted the last search on March 9, 2024. All study types investigating pharmaceutical cannabidiol in children with DEEs were considered eligible, with no language or date restrictions. Risk of bias was assessed using RoB2 and ROBINS-I V2. Results: Of the 722 records identified, 14 met the inclusion criteria. The included studies varied in design and involved a total of 682 children. Cannabidiol was administered to a maximum dose of 50mg/kg/day. Almost all studies reported positive outcomes with cannabidiol, leading to a reduction of a 50% or above in seizure frequency in at least 20% of patients included in 11 studies. Adverse events were relatively common across studies and included somnolence, loss of appetite, diarrhea, fatigue, and increased serum aminotransferases. Most of them were mild to moderate and reversible. Conclusions: Cannabidiol is generally well tolerated and has been shown to effectively reduce seizure frequency in children with DEEs whose seizures are refractory to concomitant antiepileptic medications. Future research should explore the long-term effects of cannabidiol on seizure control, developmental outcomes, and quality of life in this population.