Cannabis Company GW Pharmaceuticals’ Seizure Drug Flunks Phase II Trial
GW Pharmaceuticals Ltd. announced that its pipeline compound GWP42006 failed to meet its primary endpoint in a Phase IIa proof of concept study for patients with focal seizures.
GWP42006 features cannabidivarin (CBDV), the primary cannabinoid molecule. The drug has shown anti-epileptic properties in both in vitro and in vivo models of epilepsy, and is also being evaluated in autism spectrum disorders (ASD).
The trial was of 162 adults patients with inadequately controlled focal seizures. The trial was conducted primarily in Eastern Europe. Both active and placebo arms of the trial had similar reductions in focal seizures of approximately 40 percent, which is greater than expected for both arms of the trial. The drug was generally well tolerated. About 73 percent of patients in the active group displayed emergent adverse events compared to 48 percent in the placebo group. Most patients in the active group’s adverse events were mild or moderate in severity, and the incidence was low.
A parallel study is evaluating the compound in general and syndromic pre-clinical models of ASD, and has shown positive signals in cognitive and social endpoints in addition to repetitive behavior. The company plans to continue its clinical initiatives in ASD, which will include a physician-led expanded access IND in 10 patients with autism, as well as open-label and Phase II placebo-controlled trials in Rett syndrome. Data from the expanded access IND are expected later this year.
“GW’s R&D focus has evolved in the last few years towards pediatric neurology where we have generated significant positive clinical data,” said Justin Gover, GW’s chief executive officer, in a statement. “Whilst the results of this adult focal seizure study for GWP42006 are disappointing, we remain committed to advancing this pipeline compound to address unmet needs in the field of autism spectrum disorders, in which a promising body of preclinical data has already been generated, as well as continuing to explore the product’s potential within the field of epilepsy.”
The company’s lead program is Epidiolex, a proprietary oral solution of pure plant-derived cannabidiol, or CBD. It has been evaluated in severe, orphan, early-onset, treatment-resistant epilepsy syndromes that include Dravet syndrome, Lennox-Gastaut syndrome (LGS), Tuberous Sclerosis Complex (TSC) and Infantile Spasms (IS).
On February 5, the European Medicines Agency (EMA) accepted GW’s Marketing Authorization Application (MAA) for Epidiolex for adjunctive treatment of seizures associated with Lennox-Gastaut syndrome and Dravet syndrome. The U.S. Food and Drug Administration (FDA) gave it Orphan Drug Designation for Dravet syndrome, LGS, TSC and IS, as well as Fast Track Designation for Dravet syndrome and a conditional grant of rare pediatric disease designation. A decision by the FDA is expected by June 27, 2018.
Gover said, “The company’s top priority in 2018 remains Epidiolex, for which we have generated compelling positive data in three Phase III trials, and which is currently under regulatory review in the U.S. and Europe. We are very excited at the prospect of launching this potential breakthrough treatment later this year in the U.S., whilst continuing to progress our broad and innovative cannabinoid pipeline.”