Virginia Thornley, M.D., Neurologist, Epileptologist
March 31, 2018
Lennox-Gastaut Syndrome is an epileptic syndrome starting in childhood characterized by a wide spectrum of seizures and slow spike and wave on EEG. The seizures are characterized by the classic mnemonic “a fall, a jerk and a stare” or atonic seizures, myoclonus and complex partial seizures, although there are many other different types. Slow spike and wave generalized epileptiform discharges of 2.5 Hertz or less on electroencephalogram clinch the diagnosis. Patients are often delayed in development. Controlling seizures, because of the sheer complexity, of the different types is often a medical challenge.
Methods of the study
A new study using cannabidiol, which is the non-psychoactive medical component of the cannabis sativa plant, was carried out with the results recently demonstrating value. It covered 24 sites from the U.S., the Netherlands and Poland and studied seizures in patients medically refractory to medications using cannabidiol as an adjunctive add-on agent. 171 patients were enrolled from April 28, 2015, to October 15, 2015, and were randomly assigned to either the placebo control or the group with cannabidiol. 86 received cannabidiol and 85 were in the placebo group. 14 discontinued treatment in the cannabidiol group and 1 in the placebo group. All patients had at least one dose of treatment. Eligible patients ranged from 2-55 years old. Cannabidiol was given at a dose of 20mg/kg.
The results were startling, there was a reduction of seizures by 43.9% in the cannabidiol group and 21% in the control group. 86% patients had side effects in the cannabidiol group and 69% in the control group on placebo. These included somnolence, pyrexia, diarrhea, reduced appetite, and vomiting. 12 stopped in the cannabidiol group due to adverse reactions considered mild to moderate while 1 withdrew from the placebo group. 1 died due to unrelated causes from the cannabidiol group.
Reviewing this study, perhaps one of my critiques of this study is that the dosage was 20mg/kg in a 14-week study which means that within 14 weeks a patient of 50 kg. would have been ramped up to about 1000mg. In real life practice, medications are titrated more gradually over a period of months before maximum efficacy may be seen and in such a gradual way in order to avoid side effects. Although a large percentage of patients had side effects which were mild to moderate, it is quite possible they may have needed a smaller dose and the dosages were increased more than it was necessary to achieve the beneficial effects seen in the study within a short period of time. Nevertheless, the bottom line is that cannabidiol, a product of the Cannabis sativa plant, shows a reduction in seizures in a patient with Lennox-Gastaut syndrome.
This study concluded that there is some efficacy of cannabidiol in Lennox-Gastaut syndrome, one of the most difficult epileptic syndromes to treat, and was found with only very mild to moderate side effects. An open-label study as an extension to this study is currently ongoing.
- Thiele, et al,. “Cannabidiol in patients with seizures from Lennox Gastaut Syndrome (GWPCARE4): a randomized, double-blind placebo-controlled phase 3 trial,” Lancet, 2018, Jan., 390 (10125):1085-1096.