Fenfluramine in the treatment of Dravet syndrome: Results of a third randomized, placebo-controlled clinical trial.

OBJECTIVE: This study was undertaken to assess the safety and efficacy of fenfluramine in the treatment of convulsive seizures in patients with Dravet syndrome. METHODS: This multicenter, randomized, double-blind, placebo-controlled, parallel-group, phase 3 clinical trial enrolled patients with Dravet syndrome, aged 2-18 years with poorly controlled convulsive seizures, provided they were not also receiving stiripentol. Eligible patients who had ≥6 convulsive seizures during the 6-week baseline period were randomized to placebo, fenfluramine .2 mg/kg/day, or fenfluramine .7 mg/kg/day (1:1:1 ratio) administered orally (maximum dose = 26 mg/day). Doses were titrated over 2 weeks and maintained for an additional 12 weeks. The primary endpoint was a comparison of the monthly convulsive seizure frequency (MCSF) during baseline and during the combined titration-maintenance period in patients given fenfluramine .7 mg/kg/day versus patients given placebo. RESULTS: A total of 169 patients were screened, and 143 were randomized to treatment. Mean age was 9.3 ± 4.7 years (±SD), 51% were male, and median baseline MCSF in the three groups ranged 12.7-18.0 per 28 days. Patients treated with fenfluramine .7 mg/kg/day demonstrated a 64.8% (95% confidence interval = 51.8%-74.2%) greater reduction in MCSF compared with placebo (p < .0001). Following fenfluramine .7 mg/kg/day, 72.9% of patients had a ≥50% reduction in MCSF compared with 6.3% in the placebo group (p < .0001). The median longest seizure-free interval was 30 days in the fenfluramine .7 mg/kg/day group compared with 10 days in the placebo group (p < .0001). The most common adverse events (>15% in any group) were decreased appetite, somnolence, pyrexia, and decreased blood glucose. All occurred in higher frequency in fenfluramine groups than placebo. No evidence of valvular heart disease or pulmonary artery hypertension was detected. SIGNIFICANCE: The results of this third phase 3 clinical trial provide further evidence of the magnitude and durability of the antiseizure response of fenfluramine in children with Dravet syndrome.

Fenfluramine provides clinically meaningful reduction in frequency of drop seizures in patients with Lennox-Gastaut syndrome: Interim analysis of an open-label extension study.

OBJECTIVE: This study was undertaken to evaluate the long-term safety and effectiveness of fenfluramine in patients with Lennox-Gastaut syndrome (LGS). METHODS: Eligible patients with LGS who completed a 14-week phase 3 randomized clinical trial enrolled in an open-label extension (OLE; NCT03355209). All patients were initially started on .2 mg/kg/day fenfluramine and after 1 month were titrated by effectiveness and tolerability, which were assessed at 3-month intervals. The protocol-specified treatment duration was 12 months, but COVID-19-related delays resulted in 142 patients completing their final visit after 12 months. RESULTS: As of October 19, 2020, 247 patients were enrolled in the OLE. Mean age was 14.3 ± 7.6 years (79 [32%] adults) and median fenfluramine treatment duration was 364 days; 88.3% of patients received 2-4 concomitant antiseizure medications. Median percentage change in monthly drop seizure frequency was -28.6% over the entire OLE (n = 241) and -50.5% at Month 15 (n = 142, p < .0001); 75 of 241 patients (31.1%) experienced ≥50% reduction in drop seizure frequency. Median percentage change in nondrop seizure frequency was -45.9% (n = 192, p = .0038). Generalized tonic-clonic seizures (GTCS) and tonic seizures were most responsive to treatment, with median reductions over the entire OLE of 48.8% (p < .0001, n = 106) and 35.8% (p < .0001, n = 186), respectively. A total of 37.6% (95% confidence interval [CI] = 31.4%-44.1%, n = 237) of investigators and 35.2% of caregivers (95% CI = 29.1%-41.8%, n = 230) rated patients as Much Improved/Very Much Improved on the Clinical Global Impression of Improvement scale. The most frequent treatment-emergent adverse events were decreased appetite (16.2%) and fatigue (13.4%). No cases of valvular heart disease (VHD) or pulmonary arterial hypertension (PAH) were observed. SIGNIFICANCE: Patients with LGS experienced sustained reductions in drop seizure frequency on fenfluramine treatment, with a particularly robust reduction in frequency of GTCS, the key risk factor for sudden unexpected death in epilepsy. Fenfluramine was generally well tolerated; VHD or PAH was not observed long-term. Fenfluramine may provide an important long-term treatment option for LGS.

Fenfluramine treatment is associated with improvement in everyday executive function in preschool-aged children (<5 years) with Dravet syndrome: A critical period for early neurodevelopment.

OBJECTIVE: To evaluate whether fenfluramine (FFA) is associated with improvement in everyday executive function (EF)-self-regulation-in preschool-aged children with Dravet syndrome (DS). METHODS: Children with DS received placebo or FFA in one of two phase III studies (first study: placebo, FFA 0.2 mg/kg/day, or FFA 0.7 mg/kg/day added to stiripentol-free standard-of-care regimens; second study: placebo or FFA 0.4 mg/kg/day added to stiripentol-inclusive regimens). Everyday EF was evaluated at baseline and Week 14-15 for children aged 2-4 years with parent ratings on the Behavior Rating Inventory of Executive Function®-Preschool (BRIEF®-P); raw scores were transformed to T-scores and summarized in Inhibitory Self-Control Index (ISCI), Flexibility Index (FI), Emergent Metacognition Index (EMI), and Global Executive Composite (GEC). Clinically meaningful improvement and worsening were defined using RCI ≥ 90% and RCI ≥ 80% certainty, respectively. The associations between placebo vs FFA combined (0.2, 0.4, and 0.7 mg/kg/day) or individual treatment groups and the likelihood of clinically meaningful change in BRIEF®-P indexes/composite T-scores were evaluated using Somers'd; pairwise comparisons were calculated by 2-sided Fisher's Exact tests (p ≤ 0.05) and Cramér's V. RESULTS: Data were analyzed for 61 evaluable children of median age 3 years (placebo, n = 22; FFA 0.2 mg/kg/day, n = 15; 0.4 mg/kg/day [with stiripentol], n = 10; 0.7 mg/kg/day, n = 14 [total FFA, n = 39]). Elevated or problematic T-scores (T ≥ 65) were reported in 55% to 86% of patients at baseline for ISCI, EMI, and GEC, and in ∼33% for FI. Seventeen of the 61 children (28%) showed reliable, clinically meaningful improvement (RCI ≥ 90% certainty) in at least one BRIEF®-P index/composite, including a majority of the children in the FFA 0.7 mg/kg/day group (9/14, 64%). Only 53% of these children (9/17) also experienced clinically meaningful reduction (≥50%) in monthly convulsive seizure frequency, including 6/14 patients in the FFA 0.7 mg/kg/day group. Overall, there were positive associations between the four individual treatment groups and the likelihood of reliable, clinically meaningful improvement in all BRIEF®-P indexes/composite (ISCI, p = 0.001; FI, p = 0.005; EMI, p = 0.040; GEC, p = 0.002). The FFA 0.7 mg/kg/day group showed a greater likelihood of reliable, clinically meaningful improvement than placebo in ISCI (50% vs 5%; p = 0.003), FI (36% vs 0%; p = 0.005), and GEC (36% vs 0%; p = 0.005). For EMI, the FFA 0.7 mg/kg/day group showed a greater likelihood of reliable, clinically meaningful improvement than the FFA 0.2 mg/kg/day group (29% vs 0%; p = 0.040), but did not meet the significance threshold compared with placebo (29% vs 5%; p = 0.064). There were no significant associations between treatment and the likelihood of reliable, clinically meaningful worsening (p > 0.05). SIGNIFICANCE: In this preschool-aged DS population with high baseline everyday EF impairment, FFA treatment for 14-15 weeks was associated with dose-dependent, clinically meaningful improvements in regulating behavior, emotion, cognition, and overall everyday EF. These clinically meaningful improvements in everyday EF were not entirely due to seizure frequency reduction, suggesting that FFA may have direct effects on everyday EF during the early formative years of neurodevelopment.

Fenfluramine significantly reduces day-to-day seizure burden by increasing number of seizure-free days and time between seizures in patients with Dravet syndrome: A time-to-event analysis.

OBJECTIVE: The number, unpredictability, and severity of seizures experienced by patients with Dravet syndrome (DS) negatively impact quality of life (QOL) for patients, caregivers, and families. Metrics are needed to assess whether patients with residual seizures have moved meaningfully toward seizure freedom after treatment with new antiseizure medications. METHODS: We evaluated the time required postrandomization for each patient to experience the same number of seizures experienced during baseline (i.e., time-to-nth seizure), using a post hoc time-to-event (TTE) analysis of data from two Phase 3 placebo-controlled trials of adjunctive fenfluramine for DS (Study 1, N = 119; Study 2, N = 87). Patients aged 2-19 years were randomized to placebo or adjunctive fenfluramine (Study 1: .7 mg/kg/day or .2 mg/kg/day; Study 2: .4 mg/kg/day with stiripentol). Data were analyzed by Kaplan-Meier TTE curves and waterfall plots. RESULTS: The proportion of patients who never reached baseline seizure frequency was greater with fenfluramine than with placebo (Study 1: fenfluramine .7 mg/kg/day, 60%; fenfluramine .2 mg/kg/day, 31%; placebo, 13%; Study 2: fenfluramine .4 mg/kg/day, 58%; placebo, 2%). Median time-to-nth seizure was longer after fenfluramine than after placebo (Study 1: fenfluramine .7 mg/kg/day, 13 weeks; .2 mg/kg/day, 10 weeks; placebo, 7 weeks; Study 2: fenfluramine .4 mg/kg/day, 13 weeks; placebo, 5 weeks; p < .001). Longest duration of convulsive seizure-free days was increased in active groups versus the placebo group (Study 1: fenfluramine .7 and .2 mg/kg/day, 25.0 and 15.0 days; placebo, 9.5 days [p = .0001; p = .0352]; Study 2: fenfluramine .4 mg/kg/day, 22.0 days; placebo, 13.0 days [p = .004]). The most common adverse events included decreased appetite, pyrexia, upper respiratory tract infection, diarrhea, and fatigue. SIGNIFICANCE: These data demonstrate that fenfluramine can significantly reduce day-to-day seizure burden in patients with DS, providing prolonged periods of convulsive seizure-free days, which may help reduce the physical and emotional disease toll while improving health-related QOL for patients and caregivers.

Improved everyday executive functioning following profound reduction in seizure frequency with fenfluramine: Analysis from a phase 3 long-term extension study in children/young adults with Dravet syndrome.

OBJECTIVE: Individuals with Dravet syndrome (DS) experience frequent pharmacoresistant seizures beginning in infancy. Most exhibit poor neurodevelopmental outcomes including motor function difficulties, behavior problems, and cognitive impairment. Cognitive deficits in children with DS have been associated with seizure frequency and antiseizure medication (ASM) use. Recent research in children and young adults with DS has begun to examine the role of executive functions (EFs), as these include higher-order cognitive functions and may mediate the relationship between risk factors and cognitive impairment. Current conceptualizations, however, of EFs involve the broader self-regulation of cognitive, behavioral, and emotional domains. We explored relationships between reduction in convulsive seizure frequency and everyday EFs in a subset of children and young adults with DS treated with adjunctive fenfluramine for 1 year. METHODS: This is a post-hoc analysis of data from children and young adults with Dravet syndrome aged 5-18 years who participated in a phase 3 randomized, placebo-controlled clinical trial (core study) followed by completion of at least 1 year of fenfluramine treatment in an open-label extension (OLE) study. Eligible children and young adults started the OLE study at 0.2 mg/kg/day fenfluramine and were titrated to optimal seizure control and tolerability (maximum daily dose: 26 mg/day). Parents/caregivers documented convulsive seizure frequency per 28 days (i.e., monthly convulsive seizure frequency [MCSF]) by electronic diary. A parent/caregiver for each child also completed the Behavior Rating Inventory of Executive Function (BRIEF®) parent form, a questionnaire capturing parents'/caregivers' perceptions of everyday EF that was included as a safety measure to assess treatment-related adverse effects on EF during the trial. Ratings on BRIEF® were mapped to the current edition, the BRIEF®2 parent form, and were used to calculate T-scores for the Behavior Regulation Index (BRI), Emotion Regulation Index (ERI), Cognitive Regulation Index (CRI), and Global Executive Composite (GEC). Change in BRIEF®2 T-scores from baseline in the core study to Year 1 of the OLE study was calculated. Spearman's rho correlation coefficients assessed associations between change in BRIEF®2 indexes/composite T-scores and percentage change in MCSF. Children and young adults were divided into 2 groups based on percentage of MCSF reduction achieved from pre-randomization baseline in the core study to Year 1 of the OLE study: <50% and ≥50% MCSF reduction. Changes in the distribution of BRIEF®2 indexes/composite T-scores were compared between MCSF reduction groups using Mann-Whitney U tests. The proportions of children and young adults in these groups who showed clinically meaningful improvement in everyday EF, defined as Reliable Change Index (RCI) values ≥95% certainty relative to a reference population of neurotypically developing healthy volunteers, were then assessed by cross-tabulations and Somers' D tests (p ≤ 0.05). When there was a significant meaningful improvement in an index score, post-hoc analyses using the same statistical methods were conducted to evaluate the individual BRIEF®2 scales composing that index. Supplemental analyses examined the proportions of patients in MCSF reduction groups <25% and ≥75% who achieved clinically meaningful improvement or worsening in everyday EF using RCI values ≥95% certainty and ≥80% certainty, respectively, relative to the reference population. RESULTS: At the time of analysis, 58 children and young adults (mean age: 11 ±â€¯4 years) had reached OLE Year 1 of fenfluramine treatment with a 75% median percentage reduction in seizure frequency from pre-randomization baseline. Overall, there was a significant correlation between change in MCSF and change in BRIEF®2 T-scores for ERI (p = 0.008), but not for BRI, CRI, or GEC (p > 0.05). At OLE Year 1, 78% (n = 45) of total children/young adults had ≥50% MCSF reduction (50% [n = 29] achieved ≥75% MCSF reduction) and 22% (n = 13) of total children/young adults had <50% MCSF reduction (12% [n = 7] showed <25% MCSF reduction). The ≥50% MCSF reduction group was significantly more likely to achieve clinically meaningful improvement (RCI ≥ 95% certainty) in ERI (p = 0.002) and in CRI (p = 0.001) than the <50% MCSF reduction group. There were no significant differences in the proportions of children and young adults in the 2 MCSF reduction groups showing clinically meaningful worsening (RCI ≥ 80% certainty) on the BRIEF®2 indexes/composite. SIGNIFICANCE: In children and young adults with DS, the magnitude of reduction in MCSF after long-term treatment with adjunctive fenfluramine was associated with clinically meaningful levels of improvement in everyday EF. Seventy-eight percent (78%) of children and young adults treated with adjunctive fenfluramine for 1 year in the OLE study achieved ≥50% reduction in MCSF, for a magnitude of efficacy associated with a significantly greater likelihood of experiencing clinically meaningful improvement in emotion regulation and cognitive regulation.

An Emerging Role for Sigma-1 Receptors in the Treatment of Developmental and Epileptic Encephalopathies.

Developmental and epileptic encephalopathies (DEEs) are complex conditions characterized primarily by seizures associated with neurodevelopmental and motor deficits. Recent evidence supports sigma-1 receptor modulation in both neuroprotection and antiseizure activity, suggesting that sigma-1 receptors may play a role in the pathogenesis of DEEs, and that targeting this receptor has the potential to positively impact both seizures and non-seizure outcomes in these disorders. Recent studies have demonstrated that the antiseizure medication fenfluramine, a serotonin-releasing drug that also acts as a positive modulator of sigma-1 receptors, reduces seizures and improves everyday executive functions (behavior, emotions, cognition) in patients with Dravet syndrome and Lennox-Gastaut syndrome. Here, we review the evidence for sigma-1 activity in reducing seizure frequency and promoting neuroprotection in the context of DEE pathophysiology and clinical presentation, using fenfluramine as a case example. Challenges and opportunities for future research include developing appropriate models for evaluating sigma-1 receptors in these syndromic epileptic conditions with multisystem involvement and complex clinical presentation.

Psychosocial impact on siblings of patients with developmental and epileptic encephalopathies.

OBJECTIVE: Caring for children with developmental and epileptic encephalopathies (DEEs) places substantial demands on the entire family unit, including siblings. The Sibling Voices Survey assesses parental and sibling responses to questions designed to assess how children adapt to growing up with siblings with DEE. METHODS: Participants responded to 1 of 4 online, age- and role-specific surveys (9-12, 13-17, and ≥18-year-old [adult] siblings; parents responded with perceptions of their unaffected child's/children's feelings). Survey questions used visual analog scales, categorical responses, and free-form responses. RESULTS: Survey submissions (n = 248) included 128 parents and 120 siblings (9- to 12-year-olds, n = 24; 13- to 17-year-olds, n = 17; adults, n = 79). All groups identified home life as the most substantially affected area of their lives (71%-84%), compared with interactions at school (21%-32%) or with friends (28%-42%). The most difficult aspect across all sibling groups was "feeling worried/scared when their sibling has seizures" (58%-70%). Feeling "overly responsible" for the sibling was reported by most adult siblings (63%), 41% of 13- to 17-year-old siblings, and 34% of parents. Siblings reported more symptoms of depressed mood (e.g., "down/unhappy," 47%-62%) than their parents perceived them feeling (25%). Most sibling groups (29%-49%) reported more symptoms of anxious mood (e.g., "nightmares/bad dreams") than parents perceived (15%). Identification of potential helpful coping mechanisms varied by age group. Most respondents (68%-76%) reported positive aspects, including greater maturity and compassion. SIGNIFICANCE: The Sibling Voices Survey provided important insights into how DEE impacts siblings psychologically and socially. This study highlights the need for increased awareness among parents and healthcare providers to monitor siblings for potential signs of depressed or anxious mood, to provide proper support, and to decrease potential for negative long-term consequences.

Development and validation of the University of Washington caregiver stress and benefit scales for caregivers of children with or without serious health conditions.

PURPOSE: To develop item response theory (IRT)-based item banks and short forms to measure stress and benefit related to caregiving for children, including children with epilepsy or other serious health conditions. METHODS: Items developed with feedback from neurologists and caregivers of children with epilepsy were tested in cognitive interviews and administered to caregivers of children with severe epilepsy (N = 128), down syndrome (N = 143) and muscular dystrophy (N = 129), as well as a community sample of US caregivers (N = 322). IRT was used to analyze the data. Test-retest reliability was assessed using a two-way random effects (2,1) intraclass correlation coefficient (ICC). Validity was assessed by a pattern of correlations with relevant constructs (stress, depression, anxiety, and resilience) and by the pattern of scores by known groups. RESULTS: Caregivers of children with serious health conditions reported more stress and less benefit than the general sample. The final caregiver stress item bank (k = 19) and the caregiver benefit item bank (k = 13) were calibrated using IRT and centered on a sample of community caregivers representative of the US general caregiver population. Short form scores are highly correlated with full bank scores (r ≥ 0.98) and IRT reliability exceed 90% for most levels. Test-retest reliability was high (ICC > 0.92) for banks and short forms. CONCLUSIONS: Results provide strong support for reliability and validity of the caregiver stress and benefit scores. Instruments are publicly available, flexible, brief, and provide reliable and valid scores of caregiver stress and benefit of caregivers of children with and without serious health conditions.

A pilot, open-label study of the effectiveness and tolerability of low-dose ZX008 (fenfluramine HCl) in Lennox-Gastaut syndrome.

OBJECTIVE: Lennox-Gastaut syndrome (LGS) is a drug-resistant, childhood onset electroclinical epilepsy syndrome with multiple seizure types and diagnostic electroencephalogram findings. ZX008 (fenfluramine HCl oral solution) was well tolerated and reduced seizure frequency in Dravet syndrome, prompting this phase 2, open-label, dose-finding study of add-on ZX008 in patients with LGS (NCT02655198). METHODS: Eligible treatment-refractory patients with LGS aged 3-18 years with ≥4 documented convulsive seizures (CS) in the prior 4 weeks were administered adjunctive ZX008 twice daily at an initial dose of 0.2 mg/kg/d, with incremental dose escalations up to 0.8 mg/kg/d or 30 mg/d (maximum dose) every 4 weeks in nonresponders (<50% reduction in CS frequency). After 20 weeks (core study), responders were offered entry into a long-term extension study. Seizures were captured via diary. Cardiac safety was monitored by Doppler echocardiography and electrocardiogram. RESULTS: Thirteen patients were enrolled (mean age = 11.7 years, range = 3-17). Ten (77%) patients completed 20 weeks of ZX008 treatment. During the core study, there was a 53% median reduction (N = 13) in CS; median reduction was 60% in the 10 completers. Eight patients (62%) had a ≥50% CS reduction; three (23%) patients had a ≥75% reduction. Nine (69%) patients entered the long-term extension study. At 15 months (n = 9), median reduction in CS was 58%; six (67%) patients had a ≥50% reduction, and three (33%) patients had a ≥75% reduction. The most common adverse events were decreased appetite (n = 4, 31%) and decreased alertness (n = 2, 15%). No echocardiographic signs of cardiac valvulopathy or pulmonary hypertension were observed. SIGNIFICANCE: ZX008 provided clinically meaningful reduction (≥50%) in CS frequency in the majority of patients with LGS in this pilot study and was generally well tolerated. A phase 3, randomized, controlled study is ongoing.

Life impact of caregiving for severe childhood epilepsy: Results of expert panels and caregiver focus groups.

Severe epilepsy in children and young adults can significantly affect the lives of their caregivers. However, the lack of a reliable and valid measure of caregiver impact has limited our understanding of the scope and correlates of this impact, as well as our ability to measure the effects of treatments that could lessen it. The purpose of this study was to facilitate focus groups and interviews with an international group of clinician experts and caregivers to identify the most important domains that should be assessed in a measure of caregiver impact. Ten specific subdomains emerged from the panel discussions, which could be classified into the four overarching categories of physical health, mental health, social function, and financial resources. The caregivers highlighted the impact on the subdomains of sleep and fatigue as most critical. A review of existing caregiver impact measures confirmed that there is no measure currently available that assesses all of these relevant domains, indicating the need for the development of such a measure. The current findings highlight the significant life effects of caring for a child with severe epilepsy and can be used to inform the development of such a tool.

The humanistic and economic burden of Dravet syndrome on caregivers and families: Implications for future research.

We reviewed the current literature with respect to the humanistic and financial burdens of Dravet Syndrome (DS) on the caregivers of children with DS, in order to (1) identify key unanswered questions or gaps in knowledge that need to be addressed and then, based on these knowledge gaps, (2) propose a research agenda for the scientific community to address in the coming decade. The findings support the conclusion that caring for a child with DS is associated with significant humanistic burden and direct costs. However, due in part to the paucity of studies, as well as the lack of measures of specific burden domains, there remains much that is not known regarding the burden of caregiving for children with DS. To address the significant knowledge gaps in this area, research is needed that will: (1) identify the specific domains of caregivers' lives that are impacted by caring for a child with DS; (2) identify or, if needed, develop measures of caregiving impact in this area; (3) identify the factors that influence DS caregiving burden; (4) develop and evaluate the efficacy of treatments for reducing the negative impact of DS and its comorbidities on DS caregivers; (5) quantify the direct medical costs associated with DS and DS comorbidities and identify the factors that influence these costs; and (6) quantify and fully explore the indirect costs of DS. Research that addresses these goals will provide the empirical foundation needed for improving the quality of life of children with DS and their families.

Predicting Response to Subacromial Injections and Lidocaine/Tetracaine Patch from Pretreatment Pain Quality in Patients with Shoulder Impingement Syndrome.

OBJECTIVES: No existing pain treatment is effective for all pain problems, and response to pain treatment is highly variable. Knowledge regarding the patient factors that predict response to different treatments could benefit patients by providing an empirical foundation for patient-treatment matching. This study sought to test the hypothesis that improvements following two treatments thought to operate via similar mechanisms would be predicted by similar baseline pain qualities. DESIGN: Prospective prediction analysis using data from a previously published open label trial comparing a heated lidocaine/tetracaine patch versus subacromial corticosteroid injection for the treatment of pain in individuals with shoulder impingement syndrome. RESULTS: Consistent with the study hypothesis, the response to the two treatments were predicted by similar baseline pain qualities; specifically, higher baseline levels of unpleasant, electric, and sensitive pain predicted subsequent improvements in sleep interference, work/activity interference, and patient global ratings of improvement, respectively. CONCLUSIONS: The findings are consistent with the combined ideas that (1) those who have the most to gain (i.e., those reporting the highest levels of various pain qualities) can expect the best response to effective treatments and (2) different pain qualities may be associated with different types of outcomes. The findings support further research to examine how pain quality measures may be used to improve patient-treatment matching, and therefore, ultimately improve the efficiency, efficacy, and overall benefit-risk of pain treatment.

Fenfluramine increases survival and reduces markers of neurodegeneration in a mouse model of Dravet syndrome.

OBJECTIVE: In patients with Dravet syndrome (DS), fenfluramine reduced convulsive seizure frequency and provided clinical benefit in nonseizure endpoints (e.g., executive function, survival). In zebrafish mutant scn1 DS models, chronic fenfluramine treatment preserved neuronal cytoarchitecture prior to seizure onset and prevented gliosis; here, we extend these findings to a mammalian model of DS (Scn1a+/- mice) by evaluating the effects of fenfluramine on neuroinflammation (degenerated myelin, activated microglia) and survival. METHODS: Scn1a+/- DS mice were treated subcutaneously once daily with fenfluramine (15 mg/kg) or vehicle from postnatal day (PND) 7 until 35-37. Sagittal brain sections were processed for immunohistochemistry using antibodies to degraded myelin basic protein (D-MBP) for degenerated myelin, or CD11b for activated (inflammatory) microglia; sections were scored semi-quantitatively. Apoptotic nuclei were quantified by TUNEL assay. Statistical significance was evaluated by 1-way ANOVA with post-hoc Dunnett's test (D-MBP, CD11b, and TUNEL) or Logrank Mantel-Cox (survival). RESULTS: Quantitation of D-MBP immunostaining per 0.1 mm2 unit area of the parietal cortex and hippocampus CA3 yielded significantly higher spheroidal and punctate myelin debris counts in vehicle-treated DS mice than in wild-type mice. Fenfluramine treatment in DS mice significantly reduced these counts. Activated CD11b + microglia were more abundant in DS mouse corpus callosum and hippocampus than in wild-type controls. Fenfluramine treatment of DS mice resulted in significantly fewer activated CD11b + microglia than vehicle-treated DS mice in these brain regions. TUNEL staining in corpus callosum was increased in DS mice relative to wild-type controls. Fenfluramine treatment in DS mice lowered TUNEL staining relative to vehicle-treated DS mice. By PND 35-37, 55% of control DS mice had died, compared with 24% of DS mice receiving fenfluramine treatment (P = 0.0291). SIGNIFICANCE: This is the first report of anti-neuroinflammation and pro-survival after fenfluramine treatment in a mammalian DS model. These results corroborate prior data in humans and animal models and suggest important pharmacological activities for fenfluramine beyond seizure reduction. PLAIN LANGUAGE SUMMARY: Dravet syndrome is a severe epilepsy disorder that impairs learning and causes premature death. Clinical studies in patients with Dravet syndrome show that fenfluramine reduces convulsive seizures. Additional studies suggest that fenfluramine may have benefits beyond seizures, including promoting survival and improving control over emotions and behavior. Our study is the first to use a Dravet mouse model to investigate nonseizure outcomes of fenfluramine. Results showed that fenfluramine treatment of Dravet mice reduced neuroinflammation significantly more than saline treatment. Fenfluramine-treated Dravet mice also lived longer than saline-treated mice. These results support clinical observations that fenfluramine may have benefits beyond seizures.

Predicting response to pregabalin from pretreatment pain quality: clinical applications of the pain quality assessment scale.

OBJECTIVE: The aim of this study is to assess the Pain Quality Assessment Scale (PQAS) in predicting pregabalin in peripheral neuropathic pain (NP). STUDY DESIGN: Post hoc analysis of a double-blind, placebo-controlled, enriched enrollment, randomized withdrawal trial evaluating pregabalin in 99 patients with NP who completed the PQAS, which comprises 20 questions regarding individual pain domains and qualities that are scored into three scales: paroxysmal, deep, and surface. METHODS: Patients rated the average pain intensity and pain quality using the PQAS at baseline; average pain intensity was assessed again after 40 days of treatment with pregabalin. Associations between pretreatment PQAS scores and treatment response were estimated using Pearson's r. Logistic regression was used to identify pretitration PQAS scores contributing unique variance to predicting treatment response. RESULTS: Fifty participants provided baseline PQAS scores and received pregabalin for the entire length of the study. Nine of 23 PQAS baseline scales and items were significantly associated with treatment response to pregabalin: the paroxysmal and deep scales, and the items assessing the following pain domains and qualities: intensity, electric, tingling, cramping, radiating, throbbing, and deep (P values range, 0.002-0.045; rs range, 0.28-0.43). The PQAS items assessing sharp, hot, and unpleasant pain items demonstrated nonsignificant trends (P < 0.10) to be associated with treatment response. In the logistic regression analysis, pretitration PQAS scores had 77% sensitivity and 83% specificity to correctly identify pregabalin responders. Significantly correlated PQAS items had a sensitivity of 85% and specificity of 76%. CONCLUSION: Pretitration PQAS scores reliably predicted pregabalin responders in patients with NP.

Fenfluramine treatment for Dravet syndrome: Caregiver- and clinician-reported benefits on the quality of life of patients, caregivers, and families living in Germany, Spain, Italy, and the United Kingdom.

OBJECTIVE: Clinical trial data and prior preliminary research indicate that fenfluramine (FFA) provides meaningful improvements in seizure-related and quality of life (QOL) outcomes for individuals with Dravet syndrome (DS), their caregivers, and their families. This study sought to replicate and extend these preliminary findings in a new sample of individuals with DS and their families who live in European countries. METHODS: Study participants were European clinicians and parents caring for individuals with DS who had participated in an EU FFA Early Access Program. Participants completed one-on-one semi-structured interviews and were asked the extent to which they noticed changes in a number of the child's seizure- and non-seizure-related QOL domains after starting FFA treatment. Participants were also asked about the benefits of FFA treatment to the caregivers' lives and for the family unit. RESULTS: 25 parent caregivers and 16 clinicians participated. The caregivers and clinicians reported improvements in both seizure-related (i.e., reductions in seizure activity, improvements in the frequency or type of seizure triggers and post-ictal recovery times, and improved post-seizure function) and non-seizure-related (e.g., cognition, focus, alertness, speech, academic performance, behavior, sleep, motor function) QOL domains after FFA treatment in individuals with DS. Caregivers also reported improved mood and more time for things they enjoyed, felt less overwhelmed, reported better sleep quality, and had less personal and family stress; clinicians corroborated most of these reports. All clinicians (100%) and most (96%) caregivers said they would "very likely" or "quite likely" recommend FFA to others with DS. CONCLUSIONS: Real-world experience in Europe with FFA treatment is associated with meaningful improvements in many QOL domains for individuals with DS and their families; replicating findings from a previous study of DS patients and their families from the USA. Caregivers and clinicians provided specific examples of the benefits of FFA for people with DS, caregivers, and their families and are very likely to recommend FFA to others with DS.

The impact of TK2 deficiency syndrome and its treatment by nucleoside therapy on quality of life.

TK2d is an ultrarare autosomal recessive mitochondrial DNA depletion syndrome. Nucleoside therapy improves or stabilizes disease across key outcomes including survival, ambulation, and requirement for mechanical ventilation. However, little is known about the effects of nucleoside therapy treatment of TK2d from the patient's perspective. This study sought to address this knowledge gap. Participants with TK2d and/or their parents/caregivers completed online surveys with standardized health measures and interviews. During interviews, participants rated and described TK2d's impact on 13 quality of life domains, changes since starting nucleoside therapy, and if they would recommend nucleoside therapy. Twenty-five individuals participated (17 adults with TK2d, 4 parent-participant pairs, 4 parents of children with TK2d). Adult participants with TK2d had clinically meaningfully worse scores than the general population on global physical and mental health, physical function, pain interference, fatigue, anxiety, and social function. Children's mobility and pain interference were significantly worse than the general pediatric population. Physical domains most affected by TK2d were: mobility (84%), fatigue (60%), respiratory function (56%), and hospitalizations (55%). Psychosocial domains most affected were: impact on family members (39%), mood (36%), and social life (28%). Most (77%) treated patients reported improvement; whereas, 67% in the untreated group reported worsening. All participants would recommend nucleoside therapy. In summary, TK2d has significant negative impacts on most areas of life and function. Measures of fatigue, sleep, swallowing/eating, speaking, and mood, should be considered as outcomes in clinical trials and research studies. Nucleoside therapy appears to provide meaningful improvements across many health domains affected by TK2d. SYNOPSIS: The consequences of having TK2d are devastating for both those with the disorder and their families; however, nucleoside therapy appears to provide meaningful improvements across many health domains affected by TK2d.

Fenfluramine treatment for dravet syndrome: Real-world benefits on quality of life from the caregiver perspective.

OBJECTIVE: Prior research has demonstrated durable and profound reductions in seizure frequency and improvements in executive functions in individuals with Dravet syndrome (DS) who are treated with fenfluramine (FFA). This study aimed to understand the benefits of FFA from the perspective of the patients' caregivers. METHODS: Caregivers for a child with DS participated in semi-structured interviews to discuss the benefits of FFA treatment on the child with DS, the caregiver, and the family. RESULTS: 65 caregivers participated. Patients were between 2 and 33 years old and had been treated with FFA for an average of 22.7 months. The most commonly reported seizure-related benefits (> 50 % of participants) of FFA treatment included a reduction in seizure activity, fewer seizure triggers, and shorter post-ictal recovery. The most common quality of life (QOL) benefits in patients included improvements in cognitive function, alertness, and academic performance. In addition, the caregivers reported improvements in their sleep quality (74 %) and that they felt less overwhelmed (72 %) and stressed (69 %) after their children began FFA treatment. Many caregivers also reported improved relationships between the child with DS and their siblings (52 %). CONCLUSIONS: The study found that FFA treatment is associated with meaningful improvement in a large number of QOL domains both for the people with DS who received FFA and their families.

Long-term cardiovascular safety of fenfluramine in patients with Dravet syndrome treated for up to 3 years: Findings from serial echocardiographic assessments.

OBJECTIVE: To assess the cardiovascular safety of fenfluramine when used to treat children and young adults with Dravet syndrome. METHODS: Patients with Dravet syndrome who completed one of three phase 3 clinical trials of fenfluramine could enroll in the open-label extension (OLE) study (NCT02823145). All patients started fenfluramine treatment at an oral dose of 0.2 mg/kg/day. The dose was titrated based on efficacy and tolerability to a maximum of 0.7 mg/kg/day (absolute maximum 26 mg/day) or 0.4 mg/kg/day (absolute maximum 17 mg/day) in patients concomitantly receiving stiripentol. Serial transthoracic echocardiography was performed using standardized methods and blinded readings at OLE entry, after 4-6 weeks, and every 3 months thereafter. Valvular heart disease (VHD) was defined as ≥ moderate mitral regurgitation or ≥ mild aortic regurgitation combined with physical signs or symptoms attributable to valve dysfunction. Pulmonary artery hypertension (PAH) was defined as systolic pulmonary artery pressure >35 mmHg. RESULTS: A total of 327 patients (median age, 9.0 years; range, 2-19 years) have enrolled in the OLE and received ≥1 dose of fenfluramine. The median duration of treatment was 23.9 months (range, 0.2-42.6 months) and the median dose of fenfluramine was 0.44 mg/kg/day. No patient demonstrated VHD or PAH at any time during the OLE. SIGNIFICANCE/INTERPRETATION: This study, which represents the largest, longest, and most rigorous examination of cardiovascular safety of fenfluramine yet reported, found no cases of VHD or PAH. These results, combined with fenfluramine's substantial antiseizure efficacy, support a strong positive benefit-risk profile for fenfluramine in the treatment of Dravet syndrome.

Efficacy and Safety of Fenfluramine for the Treatment of Seizures Associated With Lennox-Gastaut Syndrome: A Randomized Clinical Trial.

Importance: New treatment options are needed for patients with Lennox-Gastaut syndrome (LGS), a profoundly impairing, treatment-resistant, developmental and epileptic encephalopathy. Objective: To evaluate the efficacy and safety of fenfluramine in patients with LGS. Design, Setting, and Participants: This multicenter, double-blind, placebo-controlled, parallel-group randomized clinical trial was conducted from November 27, 2017, to October 25, 2019, and had a 20-week trial duration. Patients were enrolled at 65 study sites in North America, Europe, and Australia. Included patients were aged 2 to 35 years with confirmed diagnosis of LGS and experienced 2 or more drop seizures per week during the 4-week baseline. Using a modified intent-to-treat method, data analysis was performed from November 27, 2017, to October 25, 2019. The database lock date was January 30, 2020, and the date of final report was September 11, 2021. Interventions: Patients were randomized to receive either a 0.7-mg/kg/d or 0.2-mg/kg/d (maximum 26 mg/d) dose of fenfluramine or placebo. After titration (2-week period), patients were taking their randomized dose for 12 additional weeks. Main Outcomes and Measures: Primary efficacy end point was percentage change from baseline in drop seizure frequency in patients who received 0.7 mg/kg/d of fenfluramine vs placebo. Results: A total of 263 patients (median [range] age, 13 [2-35] years; 146 male patients [56%]) were randomized to the 0.7-mg/kg/d fenfluramine group (n = 87), 0.2-mg/kg/d fenfluramine group (n = 89), or placebo group (n = 87). The median percentage reduction in frequency of drop seizures was 26.5 percentage points in the 0.7-mg/kg/d fenfluramine group, 14.2 percentage points in the 0.2-mg/kg/d fenfluramine group, and 7.6 percentage points in the placebo group. The trial met its primary efficacy end point: patients in the 0.7-mg/kg/d fenfluramine group achieved a -19.9 percentage points (95% CI, -31.0 to -8.7 percentage points; P = .001) estimated median difference in drop seizures from baseline vs placebo. More patients in the 0.7-mg/kg/d fenfluramine group achieved a 50% or greater response (22 of 87 [25%]; P = .02) vs placebo (9 of 87 [10%]). Site investigators and caregivers gave a much improved or very much improved rating on the Clinical Global Impression of Improvement scale to more patients in the 0.7-mg/kg/d fenfluramine group than patients in the placebo group (21 [26%] vs 5 [6%]; P = .001). The seizure subtype that appeared most responsive to fenfluramine was generalized tonic-clonic seizure (120 of 263 [46%]), with a decrease in frequency of 45.7% in the 0.7-mg/kg/d fenfluramine group and 58.2% in the 0.2-mg/kg/d fenfluramine group compared with an increase of 3.7% in the placebo group. Most common treatment-emergent adverse events included decreased appetite (59 [22%]), somnolence (33 [13%]), and fatigue (33 [13%]). No cases of valvular heart disease or pulmonary arterial hypertension were observed. Conclusions and Relevance: Results of this trial showed that, in patients with LGS, fenfluramine compared with placebo provided a significantly greater reduction in drop seizures and may be a particularly advantageous choice in patients who experience generalized tonic-clonic seizures. Trial Registration: ClinicalTrials.gov Identifier: NCT03355209.

Translation and cultural validation of the University of Washington Caregiver Stress and Benefit Scales.

BACKGROUND: English versions of the University of Washington Caregiver Stress (UW-CSS) and Benefit (UW-CBS) Scales were developed in the United States (US) to measure impact on caregivers of caring for a child/children. Caregiving stress and benefit are important constructs to study worldwide. The purpose of this study was to translate and validate the UW-CSS and UW-CBS into French, German, Italian, and Spanish languages. METHOD: UW-CSS and UW-CBS were translated using forward and backward translation with reconciliation. Cognitive interviews (CIs) were completed with caregivers of children < 18 years with severe epilepsy. Translated versions were also administered to at least 100 caregivers in each of the four countries: France, Germany, Italy, and Spain. Differential item functioning (DIF) analyses were used to assess linguistic and cultural bias by country. The US development sample of 722 caregivers was used as a comparison sample for DIF analyses. DIF adjusted scores were calculated to determine impact of DIF on the item response theory (IRT)-based T-score. Benefit and stress scores were also calculated and compared across countries and health condition subgroups. Finally, short forms were modified to minimize the impact of DIF on the UW-CSS and UW-CBS T-scores and to reflect feedback from CIs. RESULTS: Interviews were completed with 47 caregivers (German n = 14; Spanish n = 10; French n = 13; Italian n = 10). UW-CSS and UW-CBS were administered to 456 (German n = 117, Spanish n = 114, French n = 115, Italian n = 110) caregivers of children with and without health conditions. All stress items functioned well in CIs, though results indicated statistically significant DIF for three items in multiple countries and in the overall sample. Four of the 13 benefit items were problematic based on CI feedback, and six items showed DIF in one or more countries or in the combined sample. However, average differences between DIF adjusted and non-adjusted scores were minimal for both scales and all comparisons, indicating the impact of DIF on the total score was negligible. CONCLUSION: Modified short forms functioned well in all four of the translated versions. All language versions are freely publicly available.