New research found over a quarter of children with treatment-refractory epilepsy sustained treatment response to CBD over four years.
Purified cannabidiol (Epidiolex, CBD): new AED was approved in 2018 for Lennox-Gastaut and Dravet syndrome in children.1 A derivative of marijuana, it does not cause a high. Interim results of add-on CBD support efficacy in treatment resistant epilepsy2 begs the question: What is the long-term efficacy of CBD?
In a single center, open-label prospective study,3 there were 26 participants refractory to treatment despite an average of two AEDs:
•Mean age 9 years, 50% female•23% with Dravet syndrome•15% with Lennox-Gastaut syndrome
Add-on CBD was titrated to target of 25 mg/kg/day. Lab tests/clinical assessments were taken at regular intervals. Daily seizure frequency was recorded using patient diaries. Mean CBD duration: 21 months.
Results: 57.7% (n=15) discontinued CBD for lack of efficacy
•Most discontinued within first six months
At two years, only 34.6% (n=9) were still on CBD
>50% reduction in motor seizures (primary efficacy outcome):
•Sustained by 26.9% (n=7) over 2-4 years•11.5% (n=3) became seizure free
Adverse events were common: 80.8% (n=21)
Serious adverse events in 23.1% (n=6)
Clinically significant weight loss in 30.7% (n=8)
Which patients are more likely to respond to CBD?
Adverse events with CBD very common
26.9% of children with treatment refractory epilepsy sustained treatment response to CBD over four years
80.8% experienced adverse events
Determinants of response to CBD need further study
1. US Food and Drug Administration. FDA approves first drug comprised of an active ingredient derived from marijuana to treat rare, severe forms of epilepsy. https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm611046.htm. Accessed January 4, 2018.
2. Szaflarski JP, Bebin EM, Comi AM, et al. Long-term safety and treatment effects of cannabidiol in children and adults with treatment-resistant epilepsies: Expanded access program results. Epilepsia. 2018;59:1540-1548.
3. Sands TT, Rahdari S, Oldham MS, et al. Long-Term Safety, Tolerability, and Efficacy of Cannabidiol in Children with Refractory Epilepsy: Results from an Expanded Access Program in the US. CNS Drugs. 2018 Nov 20 [Epub ahead of print].