Physician Views – Neurologists assess positive Phase III data for GW Pharmaceuticals' Epidiolex

Earlier this week, GW Pharmaceuticals announced that a Phase III study of the experimental drug Epidiolex (cannabidiol) for the treatment of Dravet syndrome met its primary endpoint, by demonstrating a significant reduction in convulsive seizures compared with placebo.

This result increases validation of GW Pharmaceuticals' proprietary cannabinoid discovery and development platform, and represents a potential leap forward in how Dravet syndrome – a severe form of infantile-onset and therapy-resistant epilepsy – is treated.

For this particular indication, Epidiolex has already secured orphan drug and fast track designation from the FDA and, on the strength of new Phase III data, GW Pharmaceuticals will request a pre-NDA meeting with the agency to discuss its regulatory submission; prompting speculation that Epidiolex could reach the market sooner than expected.

With the drug now partially de-risked (a second Phase III study in Dravet syndrome is ongoing) and offering potential usage in other indications (two pivotal-stage studies are under way in Lennox-Gastaut syndrome), an increasingly clear route to market could bring potential suitors to the negotiating table – if they are comfortable with GW Pharmaceuticals' cannabis-derived platform.

To better ascertain how Epidiolex may be used for the treatment of Dravet syndrome – and potentially other forms of epilepsy on an off-label basis – we are polling US and EU5-based neurologists with the following questions…

Top-line data reveals that in a 120-patient, Phase III study, Epidiolex achieved a statistically significant reduction in monthly seizures (39 percent from baseline) versus placebo (13 percent) in paediatric patients with Dravet syndrome. Patients in the control arm received their standard medication and patients enrolled in the study were highly refractory seizure patients on multiple anti-epileptic drugs (AEDs; an average of three per patient). Median baseline convulsive seizure frequency was 13 per month. The study comprised a 14-week treatment period and a four-week baseline observation period.

How impressive do you consider this top-line Phase III data to be?
Not impressive
Marginally impressive
Moderately impressive
Highly impressive
Extremely impressive

How important is it that a difference in efficacy between Epidiolex and placebo was observed during the first month of treatment and was sustained over the entire treatment period?
Not important
Marginally important
Moderately important
Very important
Extremely important

Of the 61 patients who received Epidiolex in the Phase III study, eight discontinuations occurred due to serious adverse events. Versus demonstrated efficacy – and the debilitating nature of Dravet syndrome – how concerning is this?
Not concerning
Marginally concerning
Moderately concerning
Very concerning
Extremely concerning

If Epidiolex was approved for the treatment of Dravet syndrome on the basis of this (and other comparable) Phase III data, how frequently do you think the drug would be used for the broader treatment of epilepsy?
Not used
Very frequently
Extremely frequently

Key secondary endpoints from the Phase III study have yet to be presented. How important a role will a responder analysis (demonstrating what proportion of patients benefited from at least a 50 percent reduction in seizures) play in driving adoption of Epidiolex (assuming it is approved)?
Not important
Marginally important
Moderately important
Very important
Extremely important

Results and related analysis will be published for FirstWord Pharma PLUS subscribers to read, with the opportunity for non-FirstWord Pharma PLUS subscribers to purchase these findings. To be notified when poll results and analysis become available, please click here.

As always, FirstWord would very much like to receive your feedback and suggestions.

Note: FirstWord Polls are powered by MedePolls, a fast-turnaround service to conduct instant polls of up to five questions with guaranteed samples that include physicians from dozens of specialities and over 100 markets. To conduct this poll with a different audience, or an entirely different poll, contact us at

To read more Physician Views articles, click here.