Cannabidiol Shows Promise for Treatment-resistant Epilepsy in Children

A medicinal liquid form of marijuana created with the non-psychoactive cannabinoid cannabidiol shows promise as a potential treatment for children with severe epilepsy who are refractory to other treatments, according to a new study.

“So far, there have been few formal studies on this marijuana extract. These results are of great interest, especially for the children and their parents who have been searching for an answer for these debilitating seizures,” said lead author Orrin Devinsky, MD, of New York University Langone Comprehensive Epilepsy Center in New York.

In preclinical models of epilepsy, cannabidiol, a non-psychoactive component of Cannabis sativa, showed anticonvulsant activity, independent of activity at known endogenous cannabinoid receptors. Ten centers have independent, FDA-approved open-label Expanded Access Programs and have treated children and young adults with treatment-resistant epilepsies with pure cannabidiol.

The researchers collected data for this open-label cohort study on 213 patients, ranging from toddlers to adults, median age 11 years, who had severe treatment-resistant epilepsy. Etiologies included Dravet and Lennox-Gastaut (LGS) syndromes, epilepsy types that can lead to intellectual disability and lifelong seizures, as well as more than 10 other conditions. Cannabidiol was given as a liquid in a daily dose that was titrated up to 25 mg/kg. The researchers measured the number of seizures the participants had while taking the drug.

For the 137 patients who completed the 12-week study, the number of seizures decreased by an average of 54%. Among the 23 patients with Dravet syndrome who completed the study, the number of convulsive seizures was reduced by 53%. For the 11 patients with LGS who completed the study, there was a 55% reduction in the number of atonic seizures, which cause a sudden loss of muscle tone.

A total of 12 patients (6%) stopped taking the drug because of side effects. Side effects that occurred in more than 10% of participants included drowsiness (21%), diarrhea (17%), tiredness (17%) and decreased appetite (16%).

In conclusion, the researchers stated that “cannabidiol showed reductions in seizure frequency across multiple drug-resistant epilepsy syndromes and seizure types and was generally well tolerated in this open-label cohort.” Dr Devinsky said that these are early findings and larger, placebo-controlled, double-blind trials are needed to measure the effectiveness of the drug.

The researchers will present their results on Wednesday, April 22, 2015 (Abstract 9222) at the American Academy of Neurology’s 67th Annual Meeting from April 18-25 in Washington, DC.

Abstract title: Epidiolex (Cannabidiol) in Treatment Resistant Epilepsy