Positive clinical trial results for Epidiolex in Tuberous Sclerosis Complex

GW Pharmaceuticals have announced positive top-line results of a new randomised, double-blind, placebo-controlled Phase 3 clinical trial of Epidiolex in the treatment of seizures associated with Tuberous Sclerosis Complex (TSC).

TSC is a rare genetic condition that causes tumours, usually benign, to grow in many different organs of the body. The symptoms of TSC usually appear before a child is 6 months old. Epilepsy is present in over 90% of patients with TSC and is typically intractable to standard treatments.

Epidiolex is the first prescription, plant-derived cannabinoid medicine approved in the US with a licence for Lennox-Gastaut syndrome (LGS) and Dravet syndrome in patients two years of age or older. It is expected to be licenced in Europe in 2019.

In the latest trial, 224 patients with TSC were randomised to receive Epidiolex 25 mg/kg per day; Epidiolex 50 mg/kg per day or placebo for a 16-week treatment period.

Results for both the 25 and 50 mg/kg/day dose groups were similar, with seizure reductions of 48.6% and 47.5% from baseline respectively, compared to 26.5% for placebo.

This represents the fifth consecutive positive Phase 3 pivotal trial for Epidiolex.

Dr Elizabeth Thiele, Director of the Herscot Center for Tuberous Sclerosis Complex at Massachusetts General Hospital, Professor of Neurology at Harvard Medical School and the lead investigator of the trial said “Data from previous controlled clinical trials of Epidiolex have shown clinically meaningful seizure reductions and consistent safety and tolerability in children and adults with Lennox-Gastaut syndrome and Dravet syndrome. Based on the positive results of this trial in TSC patients, Epidiolex, if approved for this additional indication, may become an important treatment option also in this disease state with significant unmet medical need.”

The average age of trial participants was 14 years. On average, patients were taking 3 AEDs, having previously tried and discontinued 4 other AEDs. The most common side events in this study include somnolence; decreased appetite; diarrhea; constipation and vomiting. The incidence of some side effects were higher in the 50 mg/kg/day group as compared to the 25 mg/kg/day group.

Source: GW Pharmaceuticals Press release