Objective: To evaluate the pharmacokinetics, safety, and tolerability of brivaracetam (BRV) as 15‐min intravenous (IV) infusion and bolus (≤2‐min injection).Methods: EP0065 (ClinicalTrials.gov: NCT03405714) was a Phase 2, multicenter, open‐label trial in patients ≥1 month to <16 years of age with epilepsy. Patients received up to 5 mg/kg/day BRV (not exceeding 200 mg/day). Enrollment was sequential by descending age, depending on safety review. Outcomes included BRV plasma concentrations before and after IV administration, treatment‐emergent adverse events (TEAEs), and discontinuations due to TEAEs.Results: Fifty patients were enrolled, received BRV, and completed the trial. Twenty‐six patients (52.0%) received 15‐min infusions and 24 (48.0%) received bolus injections. Most patients (80.0%) received one IV dose. In the 15‐min infusion group, geometric mean (GeoMean) BRV concentrations 15 (±2) min (n = 21) and 3 h (±15 min) (n = 21) post dose were 1903.0 ng/mL (geometric coefficient of variation [GeoCV]: 60.7%) and 1130.3 ng/mL (58.8%), respectively. In the bolus group, GeoMean BRV concentrations 15 (±2) min (n = 19) and 3 h (±15 min) (n = 21) post dose were 1704.8 ng/mL (GeoCV: 74.5%) and 1383.9 ng/mL (85.0%), respectively. Overall, 14 patients (28.0%) had TEAEs (15‐min infusion: 8 [30.8%]; bolus: 6 [25.0%]), most commonly (≥5% of patients) somnolence (3 [6.0%]). Ten patients (20.0%) had drug‐related TEAEs (15‐min infusion: 6 [23.1%]; bolus: 4 [16.7%]). No patients discontinued due to TEAEs, and no deaths occurred.Significance: IV BRV (up to 200 mg/day) was well tolerated in patients ≥1 month to <16 years of age, regardless of whether BRV was administered as 15‐min infusion or bolus. No unexpected safety or pharmacokinetic differences were observed between patients receiving 15‐min infusions or bolus, and plasma concentrations were in the expected range. Safety results were consistent with the known safety profile of oral BRV, with no new safety concerns identified.

Objective: This study was undertaken to evaluate the long‐term safety, tolerability, and efficacy of adjunctive brivaracetam (BRV) treatment in pediatric patients with epilepsy.Methods: A phase 3, open‐label, multicenter, long‐term follow‐up trial (N01266; NCT01364597) was conducted on patients (aged 1 month to <17 years at core trial entry; direct enrollers aged 4 to <17 years) treated with BRV. Outcomes included treatment‐emergent adverse events (TEAEs), behavior assessments (Achenbach Child Behavior Checklist [CBCL], Behavior Rating Inventory of Executive Function [BRIEF]/BRIEF‐Preschool version [BRIEF‐P]), and efficacy outcomes (percent change in focal seizure frequency, 50% responder rate for all seizure types for patient subgroups <2 years and ≥2 years of age using daily record card data).Results: Of 257 patients with ≥1 dose of BRV (141 [54.9%] male; mean age = 8.0 years [SD = 4.5]), 36 patients were <2 years of age, and 72.0% of patients had a history of focal seizures. Mean BRV exposure was 3.2 patient‐years. At least one TEAE occurred in 93.4% patients, and 32.3% had serious TEAEs. Seven patients died during the trial; no deaths were considered treatment‐related. Patients ≥2 years of age had a median decrease in 28‐day adjusted focal seizure frequency of 62.9%, and 50.9% had a ≥50% response in all seizures. Patients <2 years of age had a median decrease in 28‐day adjusted focal seizure frequency of 96.9%, and 68.2% had a ≥50% response in all seizures. Kaplan–Meier estimated treatment retention was 72.7%, 64.5%, 57.8%, 53.3%, 50.1%, and 44.8% at 1, 2, 3, 4, 5, and 6 years, respectively. Mean changes (baseline to last evaluation) for all Achenbach CBCL and BRIEF‐P/BRIEF subscale scores were negative, reflecting stability/slight improvement.Significance: Long‐term adjunctive BRV treatment was generally well tolerated and efficacious in reducing seizure frequency, and had high retention rates, with generally stable cognitive/behavioral scores in pediatric patients with epilepsy.

Background: In clinical practice, the possible diagnosis of tuberous sclerosis or polycystic kidney disease is primarily based on clinical criteria, which can later be verified by genetic testing. But in the case of TSC2/PKD1 contiguous gene syndrome (TSC2/PKD1-CGS), the renal appearance of the disease is more serious. Therefore, early genetic analysis is recommended. Methods: Herein we present the report of four children with TSC2/PKD1-CGS, one involving the NTHL1 gene. We aim to emphasize the importance of genetic testing in this rare syndrome. Results: During the follow-up of tuberous sclerosis and polycystic kidney disease patients, it is essential to reappraise the diagnosis if the clinical symptoms’ appearance or onset time is unusual. Targeted genetic testing is recommended. However, early tumor formation necessitates the extension of genetic analysis. Conclusions: An appropriate evaluation of the phenotype is the cornerstone of diagnosing the rare TSC2/PKD1-CGS with the help of genetic results. In addition, malignant tumors could draw attention to an infrequent large deletion.

Developmental and epileptic encephalopathy-9 (DEE9) is characterized by seizure onset in infancy, mild to severe intellectual impairment, and psychiatric features and is caused by a mutation in the PCDH19 gene on chromosome Xq22. The rare, unusual X-linked type of disorder affects heterozygous females and mosaic males; transmitting males are unaffected. In our study, 165 patients with epilepsy were tested by Next Generation Sequencing (NGS)-based panel and exome sequencing using Illumina technology. PCDH19 screening identified three point mutations, one indel, and one 29 bp-long deletion in five unrelated female probands. Two novel mutations, c.1152_1180del (p.Gln385Serfs*6) and c.830_831delinsAA (p.Phe277*), were identified and found to be de novo pathogenic. Moreover, among the three inherited mutations, two originated from asymptomatic mothers and one from an affected father. The PCDH19 c.1682C>T and c.1711G>T mutations were present in the DNA samples of asymptomatic mothers. After targeted parental testing, X chromosome inactivation tests and Sanger sequencing were carried out for mosaicism examination on maternal saliva samples in the two asymptomatic PCDH19 mutation carrier subjects. Tissue mosaicism and X-inactivation tests were negative. Our results support the opportunity for reduced penetrance in DEE9 and contribute to expanding the genotype–phenotype spectrum of PCDH19-related epilepsy.