Long-term use of cannabidiol-enriched medical cannabis in a prospective cohort of children with drug-resistant developmental and epileptic encephalopathy.

OBJECTIVE: We report our findings regarding effectiveness, safety, and tolerability of cannabidiol (CBD)-enriched medical cannabis as add-on therapy in children with drug-resistant epileptic encephalopathies (DEEs) after a median follow-up of 20 months. METHODS: A prospective cohort study was conducted to assess effectiveness, safety, and tolerability of CBD-enriched medical cannabis oil added to standard antiseizure medications in children with drug-resistant DEE seen at a single center. RESULTS: Between October 2018 and March 2020, 59 patients were enrolled. Mean age at enrollment was 10.5 years (range, 2-17 years). Median treatment duration was 20 months (range, 12-32). Median age at first seizure was 8 months (range, 1 day - 10 years). At the end of follow-up, 78% of the children had a ≥ 50% decrease in seizure frequency and 47.5% had a > 75% decrease. Seven patients (11.9%) were seizure free. The number of seizures was reduced from a median of 305/month to 90/month, amounting to a mean reduction of 57% and a median reduction of 71% (p < 0.0001). Adverse effects were mostly mild or moderate. CBD was discontinued in 17 patients (28.8%) due to lack of response to treatment, increased seizure frequency, intolerance to the drug, or poor compliance. CONCLUSION: In children with drug-resistant DEEs, long-term treatment of CBD-enriched medical cannabis as an adjuvant therapy to antiseizure therapy was found to be safe, well tolerated, and effective. Sustained reductions in seizure frequency and improvement of aspects of daily living were observed compared to our preliminary findings.

Pharmacokinetics of cannabidiol in children with refractory epileptic encephalopathy.

Growing interest in the clinical use of cannabidiol (CBD) as adjuvant therapy for pediatric refractory epileptic encephalopathy emphasizes the need for drug treatment optimization. The aim of this study was to characterize the pharmacokinetics of CBD in pediatric patients with refractory epileptic encephalopathy receiving an oil-based oral solution. To evaluate CBD concentrations, six serial blood samples per patient were collected after the morning dose of CBD, at least 21 days after the beginning of treatment. Twelve patients who received a median (range) dose of 12.2 (5.3-19.4) mg/kg/d (twice daily) were included in the analysis. Median (range) CBD time to maximum plasma concentration, maximum plasma concentration, and area under the concentration versus time curve up to 6 hours after dosing were 3.2 hours (1.9-6.2), 49.6 ng/mL (14.4-302.0), and 226.3 ng ⋅ h/mL (70.5-861.3), respectively. CBD systemic exposure parameters were in the lower range of previous reports in pediatric patients receiving doses in a similar range. Most of our patients (83%) showed little CBD plasma level fluctuation during a dosing interval, comparable to that encountered after oral administration of an extended release drug delivery system. CDB administration was generally safe and well tolerated, and a novel levothyroxine-CBD interaction was recorded. Similar to other studies, large interindividual variability in CBD exposure was observed, encouraging the use of CBD therapeutic drug monitoring.

Electroclinical pattern in the transition from West to Lennox-Gastaut syndrome.

AIM: The aim of this study was to analyze electroclinical features of a group of patients with West syndrome (WS) who subsequently developed Lennox-Gastaut syndrome (LGS) during the transition between both syndromes. METHODS: A retrospective and descriptive study was conducted of a series of patients diagnosed with WS who developed LGS seen at Hospital de Pediatría Prof. Dr. JP Garrahan between January 2012 and January 2019. The medical charts of 170 patients with WS were analyzed. In 63 (37 %) of the children WS evolved to LGS. RESULTS: During the transition from WS to LGS four well-defined electroclinical patterns were recognized. The first corresponded to a group of patients with multiple seizure types, including epileptic spasms associated with multifocal paroxysms; the electroclinical pattern in second group showed mainly focal seizures associated with focal discharges in the EEG; the third group showed predominance of epileptic spasms and myoclonic seizures associated with diffuse spike-and-wave and polyspike-and-wave paroxysms; and the remaining group was characterized by a mixed electroclinical pattern including features of the other three groups. All patients had a neuropsychological deficit. Worsening of cognition and behavior was observed during the transition period in 11, 8, and 5 patients of groups 1, 3, and 4, respectively. CONCLUSION: Our study of the transition period from WS to LGS allowed us to recognize four well-defined electroclinical patterns. The early recognition of the different patterns could, in the future, support a more precocious prognostic evaluation.

Effectiveness of cannabidiol in a prospective cohort of children with drug-resistant epileptic encephalopathy in Argentina.

OBJECTIVE: We report our preliminary findings regarding effectiveness, safety, and tolerability of cannabidiol (CBD) added to antiepileptic therapy in a cohort of children with drug-resistant epileptic encephalopathies (EEs) with a mean follow-up of 8.5 months (range, 3-12 months). METHODS: A prospective cohort study was designed with the aim of assessing the effectiveness, safety, and tolerability of the addition of CBD to standard antiseizure medications (ASMs) in children with drug-resistant EE enrolled at a single center (Neurology Department, Hospital de Pediatría "Juan P. Garrahan", Buenos Aires, Argentina). RESULTS: Fifty patients were enrolled between October 2018 and October 2019, 49 of whom had a follow-up of at least 3 months at the time this interim analysis was performed. Mean age at enrollment was 10.5 years (range 2-16). Median age at first seizure was 7 months. Up to the last visit of each patient (follow-up 3-12 months) 39/49 children (80 %) had responded to treatment with a decrease in seizure frequency. Overall, 77.6 % of the patients had a seizure reduction of at least 25 %, 73.5 % had a ≥ 50 % reduction, and 49 % had a ≥ 75 % reduction. Mean monthly seizure frequency was reduced from 959 to 381 (median decrease from 299 to 102, range, 38-1900; median decrease 66 %, p < 0.001). All adverse effects were mild or moderate. The most common adverse effect was drowsiness (in 32 %), usually reversed by adjusting clobazam dose (in 12 children). CONCLUSION: In children with drug-resistant EEs, CBD oil as an adjuvant therapy to antiepileptic therapy seems safe, well tolerated, and effective.

Rasmussen syndrome: an atypical presentation in ten patients.

The aim of this study was to analyse the electroclinical and imaging findings and outcome of patients with Rasmussen syndrome (RS) with atypical manifestations. We conducted a retrospective, descriptive study of 10 of 44 consecutive patients with RS with atypical features, followed between 1999 and 2017. Six patients were boys and four were girls. The mean and median ages at onset of the seizures were 8.8 and 6.5 years, respectively (range: 4.6-13 years). All of the patients except one had seizures. Eight patients (80%) had epilepsia partialis continua that started at a mean age of 7.5 years (range: 7-15 years). In our series, hemiparesis without seizures was the first manifestation in three patients, one of whom had dual pathology. In two patients, the first manifestation was dyskinetic movements, followed by delayed-onset seizures associated with unilateral caudate atrophy. Two patients had a focal lesion mimicking focal cortical dysplasia as the first MRI abnormality; one of these two patients had epileptic spasms in clusters. Bilateral cerebral hemisphere involvement was observed in three patients during the course of the disease. Six of eight patients responded well to surgical treatment. Progressive hemiparesis alone or with delayed-onset seizures, dyskinetic movements associated with seizures, a focal lesion mimicking focal cortical dysplasia, and bilateral brain involvement were the atypical features recognized. Our series of patients responded well to surgery. Clinical, video-EEG, and neuroradiological follow-up is important for early confirmation of RS in order to initiate adequate management of the condition.