Promising results from a large-scale, controlled, Phase 3 clinical study of epilepsy patients being treated with cannabidiol will be presented next week at the American Academy of Neurology’s Annual Meeting in Boston on April 25.
GW Pharmaceuticals’ liquid oral formulation of cannabidiol (CBD), called Epidiolex, is one of 500 compounds found in cannabis. Unlike the well-known compound, tetrahydrocannabinol (THC), CBD does not produce a “high” as the psychoactive component is absent.
Results from the randomized, double-blind, placebo-controlled study found that almost 40 percent of people with Lennox-Gastaut syndrome (LGS) had at least a 50 percent reduction in drop seizures, compared to 15 percent taking a placebo.
LGS is a severe form of epilepsy that often results in impaired intellectual development and does not usually respond well to medications.
“Our study found that cannabidiol shows great promise in that it may reduce seizure that are otherwise difficult to control,” study author Anup Patel, M.D., of Nationwide Children’s Hospital and The Ohio State University College of Medicine said in a prepared statement.
The study involved 225 people, who for 14 weeks received either a daily higher dose of cannabidiol, a lower dose, or a placebo in addition to their current medications.
The average age of participants was 16, and prior to the study all had an average of 85 drop seizures per month. On average, participants had already tried six epilepsy drugs that were not successful, and continued to take about three epilepsy drugs during the study.
Those taking the higher 20 mg/kg daily cannabidiol dose saw an overall 42 percent decrease in drop seizures. For 40 percent of the participants, seizures were reduced by 50 percent or more.
Participants receiving the lower 10 mg/kg dose, saw an overall 37 percent decrease in drop seizures. A reduction of 50 percent or more was seen in 36 percent of patients.
Comparatively, the placebo group experienced a 17 percent decrease in drop seizures, and seizures were cut in half or more for 15 percent of the participants.
Side effects were more common in the higher dose groups, with 94 percent compared to 72 percent in those taking the placebo, but most were mild to moderate. Decreased appetite and sleepiness were the two most common side effects.
Participants receiving the CBD were more likely to report an improvement in overall condition, with 66 percent saying they had improved, compared to 44 percent of patients in the placebo group.
“Our results suggest that cannabidiol may be effective for those with Lennox-Gastaut syndrome in treating drop seizures,” Patel said. “This is important because this kind of epilepsy is incredibly difficult to treat. While there were more side effects for those taking cannabidiol, they were mostly well-tolerated. I believe that it may become an important new treatment option for these patients.”
A New Drug Application is expected to be submitted to the Food and Drug Administration later this year.