Cannabidiol in patients with seizures associated with Lennox-Gastaut syndrome (GWPCARE4): a randomised, double-blind, placebo-controlled phase 3 trial

Results of a Phase 3 randomised, double-blind, placebo-controlled trial to investigate the efficacy of cannabidiol (CBD) as add-on therapy for drop seizures (sudden falls due to seizures) in patients with treatment-resistant Lennox-Gastaut syndrome. After a 2 week dose escalation period, 171 patients across 24 clinical sites began a 12 week dosing period of 20mg/kg/day; administered as two equally divided doses morning and evening. Patients who completed treatment were eligible to enrol in an open-label extension trial.

RESULTS:

72 patients in the CBD group and 84 patients in the placebo group completed the study.

• Participants in the CBD group had a mean decrease in drop seizures compared to baseline of 43.9% compared to 21.8% in the placebo group
• Significantly more patients in the CBD group than the placebo group achieved reductions of 25% or more or 75% or more in monthly frequency of drop seizures
• Three patients in the CBD group who completed treatment were drop seizure free throughout the 12-week maintenance period; no patients in placebo group were drop seizure free
• 12 (14%) patients in the CBD group and one (1%) patient in the placebo group withdrew from the study because of adverse events. One patient died in the CBD group, but this was considered unrelated to treatment;; and 58 (78%) of 74 patients in the CBD group and 57 (97%) of 59 patients in the placebo group reported adverse events that were mild or moderate in severity

A higher occurrence of somnolence was observed in patients on antiepileptic drug regimens that included clobazam than those that did not include clobazam, or were in the placebo group.

Source: Centre for Medicinal Cannabis Research and Innovation