Effective Dosing of Cannabidiol for Lennox-Gastaut Syndrome

Dr Anup Patel discusses findings from the GWPCARE3 study of cannabidiol for the treatment of drop seizures in Lennox-Gastaut syndrome, presented at the 2017 American Academy of Neurology Annual Meeting in Boston.

I’m Anup Patel. I’m an associate professor of neurology and pediatrics at Nationwide Children’s Hospital and Ohio State University and am here today to talk to you about our study on cannabidiol for Lennox-Gastaut syndrome.

We did a randomized, double-blind, placebo-controlled trial of patients between the ages of 2 years and 55 years that had a clinical diagnosis of Lennox-Gastaut syndrome and were on at least 1 or more anti-seizure medications. We stratified them in different arms; so we did a 20 mg/kg per day dosing and a 10 mg/kg per day dosing and then a placebo arm, and they are randomized to one of those 3. What we found was patients in the 20 mg/kg per day arm had a 47% median seizure reduction, and the 10 mg/kg per day arm had a 37% median seizure reduction, and that compares to 17% reduction seen in the placebo group. And when you compare that to placebo in both arms, they were statistically significant.

Our secondary findings was what we call the responder rate; so, what percentage of patients achieved at least a 50% or more reduction of their seizures. Again in the 20 mg/kg per day arm, we saw 40% of the population had at least a 50% or more reduction and in the 10 mg/kg per day, that was like 34% compared to 15% in the placebo and again showed statistically significant differences. The other part we wanted to look at was safety. And so when you look at treatment-emergent adverse events, over 90% of patients who are on the 20 mg/kg per day arm reported at least 1; over 80% was seen in the ones in the 10 mg/kg per day, but as compared to other studies with Lennox-Gastaut syndrome, there’s a higher reportability in the placebo arm as well and we saw over 70% of patients in the placebo arm at least reporting 1 treatment-emergent adverse event.

The most common findings and reported in over 10% of the population were tiredness, decreased appetite, and diarrhea. So overall we felt that conclusions supported that this medication in both the 20 mg and 10 mg per kilogram per day showed a statistically significant benefit in the reduction of drop seizures as compared to placebo and was very well-tolerated and relatively safe.

This study had the 2 different treatment arms; the previous study for Lennox-Gastaut had 1 treatment arm and placebo. This one is unique in the sense that we did a low dose or 10 mg/kg per day dosing and then the other dose that’s been used in other studies, a 20 mg/kg per day dosing as it compares to placebo. We also looked at secondary outcomes of responder rate and an overall quality of life questionnaire called the CGIC and we saw again statistically significant improvement in those that got the medicine compared to placebo in those reportability scales.

The company Greenwich is hopefully going to submit an application to the FDA for a new drug application. We in the scientific community are hopeful that day will come sooner than later, but they are anticipating to do that before the year’s end, and then that will allow us to potentially get an FDA approved product to be able to treat future patients not included in the study with Lennox-Gastaut syndrome.

To read the full article on Dr Patel’s research, go here.

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