Image source: GW Pharmaceuticals.
After reporting that it has completed a phase 1/2 dosing study of its synthesized marijuana cannabidiol, or CBD, shares in Insys Therapeutics (INSY) climbed 6.2% today.
Today's news positions the company to play catch-up to GW Pharmaceuticals (GWPH), a medical marijuana company that's already conducting phase 3 studies of its own CBD drug, Epidiolex.
Earlier this year, GW Pharmaceuticals reported that epilepsy patients receiving Epidiolex experienced far fewer seizures per month than they had experienced previously.
The trial included 120 patients diagnosed with Dravet syndrome, a rare and tough-to-treat form of childhood onset epilepsy.
Patients in the Epidiolex trial were given either Epidiolex or placebo, and patients in the Epidiolex arm of the study experienced a statistically significantly lower number of seizures compared to placebo.
The average age of patients in the trial was 10, and nearly a third of patients were younger than 6. Over a 14-week treatment and observation period, Epidiolex reduced the number of monthly seizures by 39%. For comparison, patients on placebo saw a reduction of 13%.
Insys Therapeutics hopes that its version of CBD can deliver similar results in the future.
It's phase 1/2 study evaluated three doses of CBD: 10 mg/kg, 20 mg/kg, and 40 mg/kg. In total, 61 patients with tough-to-treat epilepsy were given one of the three doses at various trial sites across the United States. Patients included in the trial include those with Dravet syndrome and Lennox-Gastaut syndrome, another childhood onset form of epilepsy.
Insys Therapeutics didn't release any efficacy data, but the company's CEO, John Kapoor, did say that data is being analyzed and that the company's version of CBD appears to have been "generally well tolerated."
Image source: Insys Therapeutics.
Advancing care
Marijuana as a treatment for epilepsy has yet to be proven in definitive scientific studies, so GW Pharmaceuticals' findings are particularly remarkable.
If additional studies under way by GW Pharmaceuticals in Dravet syndrome and Lennox-Gastaut syndrome confirm the positive results already reported, it could eventually lead to an FDA approval that backs the use of CBD in these patients.
Results from one Lennox-Gastaut phase 3 study under way at GW Pharmaceuticals are expected by mid-year. Additional trials in both Dravet syndrome and Lennox-Gastaut should also have data available soon.
Meanwhile, Insys Therapeutics hasn't offered up a timeline for potential results for its CBD program, but it's already evaluating CBD in infantile spasms, and it plans to meet with FDA officials to discuss late-stage trial design.
According to clinicaltrials.gov, Insys Therapeutics' 20-person study in infantile spasms should wrap up in July. Clinicaltrials.gov also shows phase 3 Dravet syndrome and Lennox-Gastaut syndrome trials for Insys Therapeutics that have yet to begin, but that have an estimated primary completion date of December 2016.
Image source: GW Pharmaceuticals.
Looking ahead
GW Pharmaceutical has the lead in developing CBD for epilepsy, but Insys Therapeutics could have an advantage. Although GW Pharmaceuticals markets a THC-based medicine in Europe, it doesn't yet market any products here in the United States. For its part, Insys Therapeutics already manages a sales team in the U.S. that's responsible for marketing its opioid Subsys, a therapy for breakthrough cancer pain. It could also win FDA approval for a THC-based formulation of Marinol later this year, giving it a second source of revenue to eventually advance CBD commercialization.
Although Insys Therapeutics' existing relationships with doctors and payers could help it win market share in this indication someday, there's no guarantee its marijuana trials will pan out. Also, the company is far from a risk-free bet given reports of investigations into marketing practices for Subsys.
Nevertheless, the advance of marijuana-derived medicine for use in epileptics could be a big win for medical marijuana advocates and patients, and for that reason, investors ought to keep an eye on these companies and their progress.
