Small cap GW Pharmaceuticals (NASDAQ:GWPH) is up a whopping 127% premarket on robust volume in response to its announcement of positive results in a Phase 3 clinical trial assessing Orphan Drug- and Fast Track-tagged Epidiolex (cannabidiol) for the treatment of Dravet syndrome, a rare and catastrophic form of childhood epilepsy for which there are no approved treatments. The study met its primary endpoint of a statistically valid reduction in convulsive seizures over the 14-week treatment period compared to placebo.
The 120-subject study compared 20 mg/kg/day of Epidiolex (n=61) to placebo (n=59). On average, patients were receiving 3 anti-epileptic drugs (AEDs), having tried and failed an average of four other AEDs. Median baseline convulsive seizure frequency was 13/month. Patients receiving Epidiolex experienced a 39% reduction in monthly convulsive seizures versus 13% for placebo (p=0.01). The superiority of Epidiolex was observed in the first month of treatment and was sustained throughout the 14 weeks.
Epidiolex was generally well-tolerated in the trial. The most common adverse events (>10%) were somnolence (drowsiness), diarrhea, decreased appetite, fatigue, pyrexia (elevated body temperature), vomiting, lethargy, upper respiratory tract infection and convulsion. 84% of the AEs were mild or moderate. Ten patients Epidiolex patients experienced a serious adverse event compared to three for placebo. Eight Epidiolex patients discontinued treatment due to AEs versus one for placebo. The data will be presented at future medical meetings and will be submitted for publication.
The company plans to hold a pre-NDA meeting with the FDA as soon as feasible to discuss its regulatory submission, expected by mid-year.
A second pivotal study in Dravet in ongoing as well as two Phase 3s in Lennox-Gastaut syndrome, another form of severe childhood epilepsy.