A multicenter study on the use of purified cannabidiol for children with treatment-resistant developmental and epileptic encephalopathies.

OBJECTIVE: This descriptive, real-world, multicenter study aimed to evaluate the efficacy, safety, and tolerability of purified cannabidiol (CBD) as an add-on therapy in children with treatment-resistant developmental and epileptic encephalopathies (DEE).

METHODS: Children aged 0.5 to 16 years who met the International League against Epilepsy (ILAE) criteria for drug-resistant DEE and were treated with purified CBD at 10 different centers between March 2021 and December 2024 were included.

RESULTS: A total of 551 patients were enrolled. The mean age at CBD initiation was 8.5 years (SD 5 years; range 0.5-18). Median follow-up duration was 22 months (range 13-32). Etiologies were structural in 249 (45 %), genetic in 160 (28.8 %), immune-mediated in five (0.9 %), infectious in three (0.5 %), and unknown in 134 (24.3 %). After 12-32 months of follow-up, 279 patients (50.6 %) had a > 50 % reduction in seizure frequency, including 78 (14.2 %) who became seizure-free. A reduction of  50 % reduction in seizures and 56 (10.2 %) remaining seizure-free.

CONCLUSIONS: This study supports the use of purified CBD as an effective, safe, and well-tolerated treatment option for children with drug-resistant DEEs of diverse etiologies.