Epilepsy and cannabidiol: a guide to treatment.

The growing interest in cannabidiol (CBD), specifically a pure form of CBD, as a treatment for epilepsy, among other conditions, is reflected in recent changes in legislation in some countries. Although there has been much speculation about the therapeutic value of cannabis-based products as an anti-seizure treatment for some time, it is only within the last two years that Class I evidence has been available for a pure form of CBD, based on placebo-controlled RCTs for patients with Lennox-Gastaut syndrome and Dravet syndrome. However, just as we are beginning to understand the significance of CBD as a treatment for epilepsy, in recent years, a broad spectrum of products advertised to contain CBD has emerged on the market. The effects of these products are fundamentally dependent on the purity, preparation, and concentration of CBD and other components, and consensus and standardisation are severely lacking regarding their preparation, composition, usage and effectiveness. This review aims to provide information to neurologists and epileptologists on the therapeutic value of CBD products, principally a purified form, in routine practice for patients with intractable epilepsy.

The role of cannabinoids in epilepsy treatment: a critical review of efficacy results from clinical trials.

CBD was shown to have anti-seizure activity based on in vitro and in vivo models. However, several reports of small series or case reports of the use of cannabis extracts in epilepsy yielded contradictory results and the efficacy of cannabis use in patients with epilepsy have also been inconclusive. In 2013, the first Phase 1 trial for a purified form of CBD (Epidiolex/Epidyolex; >99% CBD), developed by GW Pharma, showed some efficacy signals and subsequently, a comprehensive program on the efficacy and tolerability of this compound for the treatment of drug-resistant epilepsies was initiated. Results of these trials led to the FDA and EMA approval respectively in 2018 and 2019 for the treatment of seizures associated with two rare epilepsies: Lennox-Gastaut syndrome (LGS) or Dravet syndrome (DS) in patients two years of age and older. Thus, CBD became the first FDA-approved purified drug substance derived from cannabis and also the first FDA-approved drug for the treatment of seizures in DS. We detail the clinical studies using purified CBD (Epidiolex/Epidyolex), including the first open interventional exploratory study and Randomized Control Ttrials for DS and LGS.

Cannabidiol as a new treatment for drug-resistant epilepsy in tuberous sclerosis complex.

OBJECTIVE: Tuberous sclerosis complex (TSC) is an autosomal-dominant genetic disorder with highly variable expression. The most common neurologic manifestation of TSC is epilepsy, which affects approximately 85% of patients, 63% of whom develop treatment-resistant epilepsy. Herein, we evaluate the efficacy, safety, and tolerability of cannabidiol (CBD), a nonpsychoactive compound derived from the marijuana plant, as an adjunct to current antiepileptic drugs in patients with refractory seizures in the setting of TSC. METHODS: Eighteen of the 56 patients who have enrolled in our current expanded-access study of cannabidiol for patients with treatment-resistant epilepsy carry a diagnosis of TSC. After an initial baseline period of 1 month, patients began treatment with CBD. The initial dose of 5 mg/kg/day was increased by 5 mg/kg/day every week up to a maximum dose of 50 mg/kg/day, if tolerated. Weekly seizure frequencies, percent change in seizure frequencies, and responder rates were calculated during the 2nd, 3rd, 6th, 9th, and 12th month of treatment with CBD. RESULTS: The median weekly seizure frequency during the baseline period was 22.0 (interquartile range [IQR] 14.8-57.4), which decreased to 13.3 (IQR 5.1-22.1) after 3 months of treatment with cannabidiol. The median percent change in total weekly seizure frequency was -48.8% (IQR -69.1% to -11.1%) after 3 months of treatment. The 50% responder rates over the course of the study were 50%, 50%, 38.9%, 50%, and 50% after 2, 3, 6, 9, and 12 months of treatment with CBD, respectively. In patients taking clobazam concurrently with CBD (n = 12), the responder rate after 3 months of treatment was 58.3%, compared to 33.3% in patients not taking clobazam (n = 6). Twelve (66.7%) of 18 patients in this study experienced at least one adverse event thought possibly related to CBD; the most common adverse events were drowsiness (n = 8, 44.4%), ataxia (n = 5, 27.8%), and diarrhea (n = 4, 22.2%). SIGNIFICANCE: Although double-blind, placebo-controlled trials are still necessary, these findings suggest that cannabidiol may be an effective and well-tolerated treatment option for patients with refractory seizures in TSC.

Drug-drug interaction between clobazam and cannabidiol in children with refractory epilepsy.

OBJECTIVE: Under an expanded access investigational new drug (IND) trial, cannabidiol (CBD) is being studied as a possible adjuvant treatment of refractory epilepsy in children. Of the 25 subjects in the trial, 13 were being treated with clobazam (CLB). Because CLB and CBD are both metabolized in the cytochrome P450 (CYP) pathway, we predicted a drug-drug interaction, which we evaluate in this article. METHODS: Thirteen subjects with refractory epilepsy concomitantly taking CLB and CBD under IND 119876 were included in this study. Demographic information was collected for each subject including age, sex, and etiology of seizures, as well as concomitant antiepileptic drugs (AEDs). CLB, N-desmethylclobazam (norclobazam; nCLB), and CBD levels were measured over the course of CBD treatment. CLB doses were recorded at baseline and at weeks 4 and 8 of CBD treatment. Side effects were monitored. RESULTS: We report elevated CLB and nCLB levels in these subjects. The mean (± standard deviation [SD]) increase in CLB levels was 60 ± 80% (95% confidence interval (CI) [-2-91%] at 4 weeks); the mean increase in nCLB levels was 500 ± 300% (95% CI [+90-610%] at 4 weeks). Nine of 13 subjects had a >50% decrease in seizures, corresponding to a responder rate of 70%. The increased CLB and nCLB levels and decreases in seizure frequency occurred even though, over the course of CBD treatment, CLB doses were reduced for 10 (77%) of the 13 subjects. Side effects were reported in 10 (77%) of the 13 subjects, but were alleviated with CLB dose reduction. SIGNIFICANCE: Monitoring of CLB and nCLB levels is necessary for clinical care of patients concomitantly on CLB and CBD. Nonetheless, CBD is a safe and effective treatment of refractory epilepsy in patients receiving CLB treatment.

The case for assessing cannabidiol in epilepsy.

Intractable epilepsies have an extraordinary impact on cognitive and behavioral function and quality of life, and the treatment of seizures represents a challenge and a unique opportunity. Over the past few years, considerable attention has focused on cannabidiol (CBD), the major nonpsychotropic compound of Cannabis sativa. Basic research studies have provided strong evidence for safety and anticonvulsant properties of CBD. However, the lack of pure, pharmacologically active compounds and legal restrictions have prevented clinical research and confined data on efficacy and safety to anecdotal reports. Pure CBD appears to be an ideal candidate among phytocannabinoids as a therapy for treatment-resistant epilepsy. A first step in this direction is to systematically investigate the safety, pharmacokinetics, and interactions of CBD with other antiepileptic drugs and obtain an initial signal regarding efficacy at different dosages. These data can then be used to plan double-blinded placebo-controlled efficacy trials. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Optimal clinical management of children receiving the ketogenic diet: recommendations of the International Ketogenic Diet Study Group.

The ketogenic diet (KD) is an established, effective nonpharmacologic treatment for intractable childhood epilepsy. The KD is provided differently throughout the world, with occasionally significant variations in its administration. There exists a need for more standardized protocols and management recommendations for clinical and research use. In December 2006, The Charlie Foundation commissioned a panel comprised of 26 pediatric epileptologists and dietitians from nine countries with particular expertise using the KD. This group was created in order to create a consensus statement regarding the clinical management of the KD. Subsequently endorsed by the Practice Committee of the Child Neurology Society, this resultant manuscript addresses issues such as patient selection, pre-KD counseling and evaluation, specific dietary therapy selection, implementation, supplementation, follow-up management, adverse event monitoring, and eventual KD discontinuation. This paper highlights recommendations based on best evidence, including areas of agreement and controversy, unanswered questions, and future research.

Pyridoxine supplementation for the treatment of levetiracetam-induced behavior side effects in children: preliminary results.

Behavioral side effects related to the use of levetiracetam (LEV) in epilepsy are increasingly being recognized. Patients followed in our center have reported improvement of these side effects after starting pyridoxine (vitamin B(6)) supplements. Using mailed questionnaires, retrospective chart reviews, and phone call follow-ups, we analyzed 42 pediatric patients who had been treated with LEV and pyridoxine. Twenty-two patients started pyridoxine after being on LEV, and significant behavioral improvement was observed in nine (41%), no effect in eight (36%), deterioration in four (18%), and an uncertain effect in one. The effects of pyridoxine supplementation were observed during the first week. The remaining patients (20) were already on pyridoxine before LEV was started, started pyridoxine and LEV at the same time, or took pyridoxine intermittently. Pyridoxine is an easily available, inexpensive, and safe therapeutic option. Given these preliminary results, we plan to conduct a placebo-controlled cross-over study to better characterize these observations.

Vagus nerve stimulation for intractable epilepsy in tuberous sclerosis complex.

OBJECTIVES: The aim of the study described here was to characterize the efficacy and safety of vagus nerve stimulation in a population of patients with tuberous sclerosis complex (TSC) and intractable epilepsy. METHODS: This retrospective study comprised 16 patients with TSC who underwent implantation of a vagus nerve stimulator for treatment of intractable epilepsy. RESULTS: The average age at vagus nerve stimulator implantation was 15 years (range: 2-44, SD: 12.5) and the average duration of follow-up on VNS was 4 years (range: 0.5-8.6, SD: 2.3). Outcome was rated class I (>80% seizure frequency reduction) in 3 (19%), class II (50-79% reduction) in 5 (31%), class III (<50% reduction) in 2 (13%), class IV (magnet benefit only) in 1 (6%), and class V (no improvement) in 5 (31%) patients. Intermittent magnet use was effective in aborting seizures in 8 (50%). Five (31%) patients reported an improved level of functioning. CONCLUSION: The findings suggest that the vagus nerve stimulation can be an effective and safe therapy for patients with TSC with intractable epilepsy.

A karate program for improving self-concept and quality of life in childhood epilepsy: results of a pilot study.

The potential cognitive and psychosocial effects of childhood epilepsy have significant implications for a child's self-image and academic achievement. This study focuses on a 10-week karate program for children and adolescents with epilepsy aimed at increasing social confidence, self-concept, and quality of life, as well as reducing parental anxiety. Eleven children (8-16 years old) and their parents participated in this questionnaire study, and complete data were available for nine of these families. Measures consisted of the Piers-Harris Children's Self-Concept Scale, the Quality of Life in Childhood Epilepsy (QOLCE) questionnaire, and the Parental Stress Index. By parental report, significant improvement in memory function and largely positive trends in quality of life on multiple subscales were observed. By child report, intellectual self-esteem and social confidence also improved. Parental stress decreased, although not significantly, suggesting a potential benefit and indicating a role for future interventions targeting family anxiety.

Treatments and perceptions of epilepsy in Kashmir and the United States: a cross-cultural analysis.

Treatments and perceptions of epilepsy have been found to vary across cultures. This study draws on a comparison of two patient samples, one from the United States (n=28), the other from Kashmir (n=29), to gauge the similarities and differences in social perceptions of epilepsy, attitudes toward conventional and alternative treatments, practice of conventional and alternative treatments, and selected quality-of-life issues. While both the Kashmiri and American patients interviewed were prescribed a similar regimen of traditional antiepileptic drugs, a wider range of drugs and treatments were available to and used by the latter. The use of adjunctive spiritual therapies was more prevalent in the Kashmiri sample, and the use of alternative, nonpharmacological therapies was more prevalent in the American sample. Quality of life for the Kashmiri patients sampled was found to be poorer in terms of educational and occupational opportunities, feelings of stigmatization, and openness with others about the illness. Although the two patient populations interviewed differed in their access to resources and approaches to the disorder, both samples were found to be similar overall in many attitudes and practices relating to epilepsy and its treatment.