What have we learned from the real-world efficacy of FFA in DS and LGS? A post-marketing study in clinical practice.

OBJECTIVE: To evaluate the effectiveness and tolerability of fenfluramine (FFA) in routine clinical practice treating real-world populations with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS). METHODS: This was a retrospective analysis of patients with DS or LGS who initiated FFA treatment from 2018 to 2022 at a single center. Patient demographics, medical history, seizure characteristics, and treatment outcomes were collected from electronic medical records. Duration of FFA treatment, dosage regimens, seizure frequency, seizure severity, improvements in cognitive, social, and motor outcomes, and adverse events were extracted and analyzed. Effectiveness was assessed using ≥50 % sustained reduction in monthly seizure frequency vs baseline for ≥2 consecutive months at 12 months; seizure freedom was a secondary measure. RESULTS: Seizure frequency data was available for 56 of 68 patients included in the study. At 12 months, 50 patients (89.3 %) remained on FFA treatment; 58 % of these patients achieved a ≥50 % sustained response and 10 % experienced seizure freedom. Cognitive, motor, and social improvement were noted in 70.7 %, 36.2 %, and 27.6 % of patients, respectively. The total number of concomitant antiseizure medications was reduced by ≥1 in 29.4 % of patients. No differences were found between DS and LGS patients in these outcomes; age at start of FFA and age at the 12-month timepoint did not have an effect. At least one AE was experienced by 59.7% of patients; in 86.5% of the cases, AEs were plausibly related to treatment. While 70.3% of AEs were self-resolving and 81.8% of the remaining patients experienced mild AEs, 1 patient experienced a serious AE unrelated to FFA which resulted in the patient's death. There were no cases of pulmonary arterial hypertension or ventricular heart disease. SIGNIFICANCE: The effectiveness and tolerability of FFA treatment in patients with DS or LGS in this retrospective analysis of real-world data were consistent with those seen in randomized clinical trials.

D-galactose Supplementation for the Treatment of Mild Malformation of Cortical Development with Oligodendroglial Hyperplasia in Epilepsy (MOGHE): A Pilot Trial of Precision Medicine After Epilepsy Surgery.

MOGHE is defined as mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy. Approximately half of the patients with histopathologically confirmed MOGHE carry a brain somatic variant in the SLC35A2 gene encoding a UDP-galactose transporter. Previous research showed that D-galactose supplementation results in clinical improvement in patients with a congenital disorder of glycosylation due to germline variants in SLC35A2. We aimed to evaluate the effects of D-galactose supplementation in patients with histopathologically confirmed MOGHE, with uncontrolled seizures or cognitive impairment and epileptiform activity at the EEG after epilepsy surgery (NCT04833322). Patients were orally supplemented with D-galactose for 6 months in doses up to 1.5 g/kg/day and monitored for seizure frequency including 24-h video-EEG recording, cognition and behavioral scores, i.e., WISC, BRIEF-2, SNAP-IV, and SCQ, and quality of life measures, before and 6 months after treatment. Global response was defined by > 50% improvement of seizure frequency and/or cognition and behavior (clinical global impression of "much improved" or better). Twelve patients (aged 5-28 years) were included from three different centers. Neurosurgical tissue samples were available in all patients and revealed a brain somatic variant in SLC35A2 in six patients (non-present in the blood). After 6 months of supplementation, D-galactose was well tolerated with just two patients presenting abdominal discomfort, solved after dose spacing or reduction. There was a 50% reduction or higher of seizure frequency in 3/6 patients, with an improvement at EEG in 2/5 patients. One patient became seizure-free. An improvement of cognitive/behavioral features encompassing impulsivity (mean SNAP-IV - 3.19 [- 0.84; - 5.6]), social communication (mean SCQ - 2.08 [- 0.63; - 4.90]), and executive function (BRIEF-2 inhibit - 5.2 [- 1.23; - 9.2]) was observed. Global responder rate was 9/12 (6/6 in SLC35A2-positive). Our results suggest that supplementation with D-galactose in patients with MOGHE is safe and well tolerated and, although the efficacy data warrant larger studies, it might build a rationale for precision medicine after epilepsy surgery.