Cannabis-based drug specialist GW Pharma saw its shares soar yesterday after reporting impressive phase III results for its epilepsy drug candidate.
Shares in the UK company closed up 136% yesterday after the company reported that its Epidiolex (liquid cannabidiol) drug was effective in controlling seizures in children with Dravet syndrome, one of the most severe forms of childhood epilepsy.
The 120-patient study revealed that patients given Epidiolex saw a 39% median reduction in monthly seizures after 14 weeks' treatment, compared to a 13% cut in the placebo group. GW has a second trial in play - involving 150 patients - which is due to generate results in the second half of the year.
"These are clinically meaningful and important reductions in seizures in otherwise treatment-resistant children," the company said in a statement, adding that there are currently no approved drugs to treat this form of epilepsy.
Chief executive Justin Gover said the firm is now planning to seek a meeting with the FDA to determine what will be required to support a marketing approval for Epidiolex in the US, both for Dravet syndrome and also for another uncommon form of paediatric epilepsy known as Lennox-Gastaut syndrome.
Two Lennox-Gastaut trials are fully enrolled and on track to generate top-line data sometime in the second quarter. GW is also planning to start a third phase III programme in tuberous sclerosis, a rare genetic condition that causes benign tumours to grow in the brain leading to seizures and other symptoms.
The company told investors on a conference call that the results are one of the most significant developments in the company's 18-year-long quest to discover cannabis-based drugs.
GW already makes fees and royalty revenues from cannabinoid-based drug called Sativex for moderate to severe spasticity in multiple sclerosis patients who have not responded adequately to other anti-spasticity drugs, netting around £4m ($5.7m) for the company in fiscal 2015.
Epidiolex is expected to be a much bigger product, however, with analysts at Edison estimating that peak sales of the drug could be as much as $1.05bn, assuming it is approved in all three indications.
Dravet syndrome affects 6,000 children in the US and roughly 10,000 in Europe, while Lennox-Gastaut affects 14,000-18,500 and 23,000-31,000 children in each region, respectively. Meanwhile, tuberous sclerosis affects as many as 25,000-40,000 individuals in the US and about one to two million individuals worldwide.
GW has been scaling up its commercial organisation and production capacity in anticipation of commercial demand for Epidiolex.