Children with Lennox-Gastaut syndrome (LGS) who were treated with the cannabinoid product Epidiolex (cannabidiol) had fewer drop seizures, according to results of a clinical trial developed by Britain’s GW Pharmaceuticals.
The Phase 3 trial (GWPCARE3, NCT02224560) showed that patients taking Epidiolex saw the number of monthly seizures fall by 50 percent or more, compared to the 15 percent reported by those on a placebo. Furthermore, the number of patients and caregivers reporting an improvement in the patient’s overall condition was higher among those treated with Epidiolex (66 percent in the low-dose group, 57 percent in the high-dose group) than in the placebo group (44 percent).
Patients tolerated Epidiolex well and reported only mild or moderate side effects including sleepiness and reduced appetite. Results will be presented April 25 during the upcoming meeting of the American Academy of Neurology in Boston.
“Lennox-Gastaut syndrome is one of the most challenging types of epilepsy to treat,” said researcher Anup Patel, MD, of Nationwide Children’s Hospital and the Ohio State University College of Medicine. “Results from this large, placebo-controlled study demonstrate that Epidiolex provides clinically meaningful reductions in seizure frequency together with an acceptable safety and tolerability profile. I believe Epidiolex has the potential to change the treatment of LGS and I am excited at the future prospect of prescribing an appropriately standardized and tested pharmaceutical formulation of cannabidiol.”
Epidiolex is an oral formulation of pure plant-derived cannabidiol, and is designed to treat treatment-resistant epilepsy syndromes such as LGS, which accounts for only 2 to 5 percent of all childhood epilepsies.
The GWPCARE3 study investigated the safety and efficacy of Epidiolex as a potential antiepileptic treatment for LGS. Children were assigned to either receive 10 mg/kg/day or 20mg/kg/day of Epidiolex or a placebo, for 14 weeks. Those on Epidiolex (94 and 84 percent in the high- and low-dose group) experienced more adverse side effects compared to the placebo group (77 percent), but side effects were mostly mild to moderate and consistent with previous safety reports.
“New results from our largest and most recently completed LGS study offer a first look at the significant efficacy of two different doses of Epidiolex added to existing anti-epileptic drug treatment over placebo,” said GW’s CEO, Justin Gover. “This latest data from our Phase 3 program reinforces the potential of Epidiolex to become an important new medicine for patients who suffer from LGS and our planned [New Drug Application] submission remains on track for the middle of this year.”
The U.S. Food and Drug Administration has granted Epidiolex orphan drug status to treat LGS, Dravet syndrome, tuberous sclerosis complex and infantile spasms — all of which are forms of treatment-resistant epilepsy. The European Medicines Agency (EMA) also granted the drug orphan status for the treatment of LGS and Dravet syndrome.