In 78 patients with drug-resistant epilepsy from diverse etiologies (not Lennox-Gastaut, Dravet, or TSC), CBD achieved 68.8% responder rate, 67.8% mean seizure reduction, and 11.5% seizure freedom over 14 months.
Read this if you have drug-resistant epilepsy not related to Lennox-Gastaut, Dravet, or TSC and want to understand the evidence for CBD.
68.8% responder ratePatients achieving 50%+ seizure reduction with CBD for non-LGS/Dravet/TSC epilepsy
What the researchers found
In this multicenter retrospective study, 78 patients (median age 24, mostly structural and genetic etiologies) with drug-resistant epilepsy received highly purified CBD as adjunctive therapy. They were on a median of 3 antiseizure drugs with a median of 30 monthly seizures. After a median 14 months of treatment, 68.8% achieved 50%+ seizure reduction, mean seizure reduction was 67.8%, and 11.5% became seizure-free. Clobazam co-use did not significantly affect efficacy or safety. Drug retention rate was 78.2%. Adverse events occurred in 28.2% but were manageable.
Why it matters
CBD (Epidiolex) is FDA-approved only for Lennox-Gastaut syndrome, Dravet syndrome, and Tuberous Sclerosis Complex. This study provides real-world evidence that CBD may be effective for drug-resistant epilepsy regardless of the underlying cause, potentially broadening its clinical use.
The numbers in context
- 78 patients, median age 24 years
- Median baseline seizures: 30/month
- Median concurrent ASDs: 3 (IQR 2-4)
- Median treatment duration: 14 months (IQR 10-17)
- 50%+ seizure reduction: 68.8%
- Mean seizure reduction: 67.8%
- Seizure freedom: 11.5%
- Drug retention: 78.2%
- Adverse events: 28.2%
How the study worked
Multicenter retrospective study evaluating highly purified CBD for drug-resistant epilepsy in patients >2 years with various etiologies (excluding LGS, Dravet, TSC). Assessed efficacy at last available visit and safety throughout treatment.
Who was studied
78 patients with drug-resistant epilepsy of diverse etiologies (structural and genetic), median age 24
What this study cannot tell us
Retrospective, uncontrolled design. No placebo comparison. Diverse etiologies make it difficult to identify which specific conditions respond best. Selection bias — patients prescribed CBD may differ systematically from those who were not.
How to read the evidence
Multicenter retrospective case series. Provides promising real-world evidence but requires controlled trials for definitive conclusions.
When this study was published
Published in 2023. Supports expanding research into CBD for epilepsy beyond currently approved indications.
The bigger picture
If CBD's antiseizure effects extend broadly across epilepsy types, the current regulatory restriction to three specific conditions may be unnecessarily limiting access for patients with other forms of drug-resistant epilepsy.
Questions still open
- Which specific epilepsy etiologies respond best to CBD?
- Would a controlled trial confirm these results in non-LGS/Dravet/TSC patients?
- Should regulatory agencies expand CBD's approved indications based on real-world evidence?
Read the original research
Real-world evidence on the use of cannabidiol for the treatment of drug resistant epilepsy not related to Lennox-Gastaut syndrome, Dravet syndrome or Tuberous Sclerosis Complex.
Seizure, 112, 72-76
Citation
Espinosa-Jovel, Camilo; Riveros, Sandra; Bolaños-Almeida, Carlos; Salazar, Mateo Ramírez; Inga, Leidy Ceballos; Guío, Laura. (2023). Real-world evidence on the use of cannabidiol for the treatment of drug resistant epilepsy not related to Lennox-Gastaut syndrome, Dravet syndrome or Tuberous Sclerosis Complex.. Seizure, 112, 72-76. https://doi.org/10.1016/j.seizure.2023.09.015