BioPharma

GW’s cannabinoid-based Epidiolex scores another Phase III epilepsy victory

The drug showed positive results in a 210-patient study in patients experiencing treatment-resistant seizures from tuberous sclerosis complex, a rare form of epilepsy.

The company that nearly a year ago became the first to receive Food and Drug Administration approval for a cannabinoid-based drug has another positive Phase III trial under its belt.

Cambridge, UK-based GW Pharmaceuticals said Monday that its Phase III trial of Epidiolex (cannabidiol) in patients aged 1 to 65 experiencing treatment-resistant seizures associated with tuberous sclerosis complex had met its primary endpoint. TSC is a rare and severe form of childhood-onset epilepsy. The drug was approved in June 2018 for seizures from two other forms of epilepsy, Lennox-Gastaut syndrome and Dravet syndrome.

Shares of GW opened Tuesday morning nearly 9 percent above their Monday closing price of $180.09 on the Nasdaq before settling back down to $184.32 in afternoon trading.

According to the data, patients receiving Epidiolex at 25mg per kilogram of body weight and those receiving it at 50mg per kilogram saw reductions in seizure frequency of 48.6 percent and 47.5 percent from baseline, respectively, compared with 26.5 percent of those on placebo. The trial enrolled 210 participants, randomized in a double-blind matter to receive the drug or placebo, according to the ClinicalTrials.gov database.

“The positive outcome of this trial of Epidiolex in patients with tuberous sclerosis complex expands both our knowledge of this newly available medicine and its potential utility beyond the current indications,” said Dr. Elizabeth Thiele, a professor of neurology at Massachusetts General Hospital and the study’s lead investigator, in a statement.

The company noted that the latest data represent the fifth consecutive Phase III trial of Epidiolex to achieve positive results, and the company expects to file for FDA approval in TSC in the fourth quarter of this year.

The company’s first quarter 2019 numbers yielded favorable news for the drug as well. Sales of Epidiolex were $33.5 million, which according to Cowen analyst Phil Nadeau was ahead of the $25-30 million that investors had expected. TSC, a genetic disorder that results from non-malignant tumors, is estimated to affect about 50,000 patients in the US, Nadeau noted. Of those, 75-90 percent have epilepsy, and a further 60 percent of them – roughly 25,000 patients – have treatment-resistant seizures. The company said last year that Epidiolex would carry a list price of $32,500 per year, in line with other branded epilepsy drugs.

Photo: PABLO PORCIUNCULA BRUNE, Getty Images