Severe communication delays are independent of seizure burden and persist despite contemporary treatments in SCN1A+ Dravet syndrome: Insights from the ENVISION natural history study.

OBJECTIVE: Dravet syndrome (DS) is a developmental and epileptic encephalopathy characterized by high seizure burden, treatment-resistant epilepsy, and developmental stagnation. Family members rate communication deficits among the most impactful disease manifestations. We evaluated seizure burden and language/communication development in children with DS. METHODS: ENVISION was a prospective, observational study evaluating children with DS associated with SCN1A pathogenic variants (SCN1A+ DS) enrolled at age ≤5 years. Seizure burden and antiseizure medications were assessed every 3 months and communication and language every 6 months with the Bayley Scales of Infant and Toddler Development 3rd edition and the parent-reported Vineland Adaptive Behavior Scales 3rd edition. We report data from the first year of observation, including analyses stratified by age at Baseline: 0:6-2:0 years:months (Y:M; youngest), 2:1-3:6 Y:M (middle), and 3:7-5:0 Y:M (oldest). RESULTS: Between December 2020 and March 2023, 58 children with DS enrolled at 16 sites internationally. Median follow-up was 17.5 months (range = .0-24.0), with 54 of 58 (93.1%) followed for at least 6 months and 51 of 58 (87.9%) for 12 months. Monthly countable seizure frequency (MCSF) increased with age (median [minimum-maximum] = 1.0 in the youngest [1.0-70.0] and middle [1.0-242.0] age groups and 4.5 [.0-2647.0] in the oldest age group), and remained high, despite use of currently approved antiseizure medications. Language/communication delays were observed early, and developmental stagnation occurred after age 2 years with both instruments. In predictive modeling, chronologic age was the only significant covariate of seizure frequency (effect size = .52, p = .024). MCSF, number of antiseizure medications, age at first seizure, and convulsive status epilepticus were not predictors of language/communication raw scores. SIGNIFICANCE: In infants and young children with SCN1A+ DS, language/communication delay and stagnation were independent of seizure burden. Our findings emphasize that the optimal therapeutic window to prevent language/communication delay is before 3 years of age.

Outcomes from a Spanish Expanded Access Program on cannabidiol treatment in pediatric and adult patients with epilepsy.

AIM: To evaluate the effectiveness and tolerability of cannabidiol (CBD) in patients with developmental and epileptic encephalopathies, including Dravet syndrome (DS), and Lennox-Gastaut syndrome (LGS), in a Spanish Expanded Access Program (EAP). METHODS: This was a multicenter, retrospective, observational study of patients treated with purified CBD in 14 hospitals across Spain. Patients with (1) written informed consent and (2) at least 6 months follow-up before the closure of the database were included. Primary effectiveness endpoints included reductions (100 %, ≥75 %, ≥50 %, ≥25 %, or 0 %) or worsening in seizure frequency (all seizure types and most disabling seizures) at 1-, 3-, 6-, and 12-month visits and at the last visit, and median relative seizure reduction between baseline and last visit. Secondary effectiveness endpoints included retention rate, reduction in seizure severity, status epilepticus, healthcare utilization, and quality of life. Primary safety endpoints included rates of adverse events (AEs) and AEs leading to discontinuation. RESULTS: One hundred and two patients (DS 12 %; LGS 59 %; other epilepsy syndromes 29 %) with a mean age of 15.9 years were enrolled. Patients were highly refractory to antiseizure medications (ASMs); mean number of prior failed ASMs was 7.5 (SD 3.7). The mean CBD dose was 13.0 mg/kg/day at the last visit. The proportion of patients with ≥50 % reduction in the total number of seizures from baseline was 44.9 % at 6 months and 38.9 % at 12 months. The median number of total seizures per month reduced by 47.6 % from baseline to the last visit. At 12 months, seizure severity was lower in 33/54 patients (61.1 %) and unchanged in 17/54 patients (31.5 %). Quality of life, based on the CAVE scale, increased from a mean score of 17.9 ± 4.7 (n = 54) at baseline to 21.7 ± 5.5 (n = 51) at the last patient visit (21.2 % improvement). The mean treatment retention time was 10.3 months. There were no statistically significant changes in the number of status epilepticus episodes, but lower healthcare utilization was observed. Adverse events occurred in sixty-eight patients (66.7 %), and the most common were somnolence (34.3 %) and diarrhea (12.7 %). Cannabidiol was discontinued exclusively due to AEs in 7.8 % of patients, increasing to 25.5 % when both lack of efficacy and AEs were considered together. CONCLUSIONS: Cannabidiol demonstrated promising effectiveness and tolerability in patients with developmental and epileptic encephalopathies taking part in a Spanish EAP.

Consensus statements on the information to deliver after a febrile seizure.

Febrile seizures (FS) are usually self-limiting and cause no morbidity. Nevertheless they represent very traumatic events for families. There is a need to identify key messages that reassure carers and help to prevent inappropriate, anxiety-driven behaviors associated with "fever phobia." No recommendations have been proposed to date regarding the content of such messages. Using a Delphi process, we have established a consensus regarding the information to be shared with families following a FS. Twenty physicians (child neurologists and pediatricians) from five European countries participated in a three-step Delphi process between May 2018 and October 2019. In the first step, each expert was asked to give 10 to 15 free statements about FS. In the second and third steps, statements were scored and selected according to the expert ranking of importance. A list of key messages for families has emerged from this process, which offer reassurance about FS based on epidemiology, underlying mechanisms, and the emergency management of FS should they recur. Interestingly, there was a high level of agreement between child neurologists and general pediatricians.Conclusion: We propose key messages to be communicated with families in the post-FS clinic setting. What is Known: • Febrile seizures (FS) are traumatic events for families. • No guidelines exist on what information to share with parents following a FS. What is New: • A Delphi process involving child neurologists and pediatricians provides consensual statement about information to deliver after a febrile seizure. • We propose key messages to be communicated with families in the post-FS clinic setting.

A survey of the European Reference Network EpiCARE on clinical practice for selected rare epilepsies.

Objective: Clinical care of rare and complex epilepsies is challenging, because evidence-based treatment guidelines are scarce, the experience of many physicians is limited, and interdisciplinary treatment of comorbidities is required. The pathomechanisms of rare epilepsies are, however, increasingly understood, which potentially fosters novel targeted therapies. The objectives of our survey were to obtain an overview of the clinical practice in European tertiary epilepsy centers treating patients with 5 arbitrarily selected rare epilepsies and to get an estimate of potentially available patients for future studies. Methods: Members of the European Reference Network for rare and complex epilepsies (EpiCARE) were invited to participate in a web-based survey on clinical practice of patients with Dravet syndrome, tuberous sclerosis complex (TSC), autoimmune encephalitis, and progressive myoclonic epilepsies including Unverricht Lundborg and Unverricht-like diseases. A consensus-based questionnaire was generated for each disease. Results: Twenty-six of 30 invited epilepsy centers participated. Cohorts were present in most responding centers for TSC (87%), Dravet syndrome (85%), and autoimmune encephalitis (71%). Patients with TSC and Dravet syndrome represented the largest cohorts in these centers. The antiseizure drug treatments were rather consistent across the centers especially with regard to Dravet syndrome, infantile spasms in TSC, and Unverricht Lundborg / Unverricht-like disease. Available, widely used targeted therapies included everolimus in TSC and immunosuppressive therapies in autoimmune encephalitis. Screening for comorbidities was routinely done, but specific treatment protocols were lacking in most centers. Significance: The survey summarizes the current clinical practice for selected rare epilepsies in tertiary European epilepsy centers and demonstrates consistency as well as heterogeneity in the treatment, underscoring the need for controlled trials and recommendations. The survey also provides estimates for potential participants of clinical trials recruited via EpiCARE, emphasizing the great potential of Reference Networks for future studies to evaluate new targeted therapies and to identify novel biomarkers.