Critical flicker fusion in patients with epilepsy under antiseizure medication

OBJECTIVE

Critical flicker frequency (CFF) and flicker frequency (FF) are used as indicators for the neurotoxic adverse events of drugs in pharmacology. In this pilot study, we investigated whether patients with epilepsy (PWE) treated with various antiseizure medications (ASM) had significantly different CFFs compared with healthy controls. In addition, we investigated the appropriateness of CFF as an objective measurement tool in PWE who reported adverse events according to the adverse event profile (AEP).

METHODS

Patients receiving regular antiseizure treatment at our center, along with healthy controls, were included in this study. Clinical neurotoxic symptoms, AEP scores, and serum ASM levels were assessed in the PWE group. We used a CFF device that produced a red-black, green-black, blue-black, or white-black flicker. CFF and FF were compared between PWE and healthy controls. In PWE, the correlation of alterations in CFF and FF with AEP results and through ASM serum concentrations was calculated.

RESULTS

A total of 33 PWE and 20 healthy controls participated in the study. Except for two light modalities, CFF and FF were significantly reduced in PWE compared with controls. CFF and FF did not differ significantly between PWE with AEP scores >44 points and those with lower scores. CFF and FF levels did not correlate with changes in AEP scores, serum concentrations, or doses.

SIGNIFICANCE

CFF and FF distinguished PWE with ASM from healthy controls. No clinically relevant differentiation was detected in the heterogenous PWE group. To investigate whether CFF and FF may serve as subtle indicators of neurotoxicity or specific modes of action, additional studies are needed in more homogenous PWE groups.

Psychiatric assessment prior to and after switch from levetiracetam to brivaracetam

PURPOSE

Brivaracetam is often used as an alternative to levetiracetam in patients with epilepsy (PWE) encountering efficacy issues or adverse events with levetiracetam. This study evaluated the psychological status of PWE who were switched from levetiracetam to brivaracetam due to psychiatric tolerability concerns in comparison to those who remained on levetiracetam.

METHODS

We used various psychological assessments including the Symptom Checklist SCL-90-R, the Beck Depression Inventory-II, and the adverse event profile. Eligible participants completed the questionnaires at baseline and again 8 days later. Psychological changes were assessed using standard statistical methods to show differences between a group that immediately switched from levetiracetam to brivaracetam and another group with unchanged levetiracetam.

RESULTS

Between May 2020 and May 2021, 63 patients participated in the study, of whom 34 switched from levetiracetam to brivaracetam. At baseline, participants who switched to brivaracetam had fewer antiseizure medications but experienced more monthly seizures. Baseline scores for anxiety (p = 0.020) and psychoticism (p = 0.046) on SCL-90-R in PWE switched to brivaracetam were higher than in the remaining group. In the subsequent assessment, all psychological scores were reduced and were no longer significantly different between both groups. Using multiple regression, initial treatment with a single antiseizure medication and male gender emerged as predictors of psychological improvement.

CONCLUSION

Our study found no increased risk of adverse events or psychiatric symptoms after switching from levetiracetam to brivaracetam. Though statistically non-significant, a trend towards improved psychiatric outcomes in the switch group warrants further investigation in future trials with stronger designs for enhanced statistical power.

Technical note: preliminary surgical experience with a new implantable epicranial stimulation device for chronic focal cortex stimulation in drug-resistant epilepsy

PURPOSE

This study is to report some preliminary surgical considerations and outcomes after the first implantations of a new and commercially available implantable epicranial stimulation device for focal epilepsy.

METHODS

We retrospectively analyzed data from clinical notes. Outcome parameters were as follows: wound healing, surgery time, and adverse events.

RESULTS

Five patients were included (17-52 y/o; 3 female). Epicranial systems were uneventfully implanted under neuronavigation guidance. Some minor adverse events occurred. Wound healing in primary intention was seen in all patients. Out of these surgeries, certain concepts were developed: Skin incisions had to be significantly larger than expected. S-shaped incisions appeared to be a good choice in typical locations behind the hairline. Preoperative discussions between neurologist and neurosurgeon are mandatory in order to allow for the optimal coverage of the epileptogenic zone with the electrode geometry.

CONCLUSION

In this first small series, we were able to show safe implantation of this new epicranial stimulation device. The use of neuronavigation is strongly recommended. The procedure is simple but not trivial and ideally belongs in the hands of a neurosurgeon.

Effectiveness and tolerability of brivaracetam in patients with epilepsy stratified by comorbidities and etiology in the real world: 12-month subgroup data from the international EXPERIENCE pooled analysis

OBJECTIVE

To assess the effectiveness and tolerability of brivaracetam (BRV) in adults with epilepsy by specific comorbidities and epilepsy etiologies.

METHODS

EXPERIENCE/EPD332 was a pooled analysis of individual patient records from several non-interventional studies of patients with epilepsy initiating BRV in clinical practice. Outcomes included ≥ 50% reduction from baseline in seizure frequency, seizure freedom (no seizures within prior 3 months), continuous seizure freedom (no seizures since baseline), BRV discontinuation, and treatment-emergent adverse events (TEAEs) at 3, 6, and 12 months. Analyses were performed for all adult patients (≥ 16 years of age) and stratified by comorbidity and by etiology at baseline (patients with cognitive/learning disability [CLD], psychiatric comorbidity, post-stroke epilepsy, brain tumor-related epilepsy [BTRE], and traumatic brain injury-related epilepsy [TBIE]).

RESULTS

At 12 months, ≥ 50% seizure reduction was achieved in 35.6% (n = 264), 38.7% (n = 310), 41.7% (n = 24), 34.1% (n = 41), and 50.0% (n = 28) of patients with CLD, psychiatric comorbidity, post-stroke epilepsy, BTRE, and TBIE, respectively; and continuous seizure freedom was achieved in 5.7% (n = 318), 13.7% (n = 424), 29.4% (n = 34), 11.4% (n = 44), and 13.8% (n = 29), respectively. During the study follow-up, in patients with CLD, psychiatric comorbidity, post-stroke epilepsy, BTRE, and TBIE, 37.1% (n = 403), 30.7% (n = 605), 33.3% (n = 51), 39.7% (n = 68), and 27.1% (n = 49) of patients discontinued BRV, respectively; and TEAEs since prior visit at 12 months were reported in 11.3% (n = 283), 10.0% (n = 410), 16.7% (n = 36), 12.5% (n = 48), and 3.0% (n = 33), respectively.

CONCLUSIONS

BRV as prescribed in the real world is effective and well tolerated among patients with CLD, psychiatric comorbidity, post-stroke epilepsy, BTRE, and TBIE.

PERPRISE: A prospective non-interventional study of PERampanel as only adjunctive treatment in patients with PRImary or SEcondarily generalized tonic-clonic seizures: First interim analysis

OBJECTIVE

To report the interim results of the PERPRISE study (Study 509; NCT04202159), which is evaluating perampanel as the only adjunctive anti-seizure medication (ASM) in adults with focal to bilateral tonic-clonic seizures (FBTCS) or primary generalized tonic-clonic seizures (GTCS).

METHODS

PERPRISE is an ongoing 12-month multicenter, prospective, observational, non-interventional study of perampanel in a real-world setting in Germany. Patients are aged ≥18 years with FBTCS or GTCS due to focal or idiopathic generalized epilepsy. Perampanel, as an adjunctive therapy to ASM monotherapy ('add-on therapy') or as a substitute for one ASM in dual therapy ('substitution therapy'), is prescribed in line with its SmPC. The Interim Analysis Set comprises the first 100 patients who received ≥1 dose of perampanel and attended or discontinued prior to the ~6-month visit. Interim endpoints include retention rate, measures of effects on seizure frequency, and treatment-emergent adverse events (TEAEs).

RESULTS

One hundred patients were included in the Interim Analysis Set (add-on, n = 43 [43.0%]; substitution, n = 55 [55.0%]; unknown, n = 2). The 6-month retention rate was 78.0% (add-on, 83.7%; substitution, 72.7%). For the overall population with GTCS and/or FBTCS, seizure-freedom rate at 6 months was 58.8% (add-on, 72.2%; substitution, 47.9%) and 50% responder rate at 6 months was 82.6% (add-on, 89.2%; substitution, 76.6%). Retention rates and seizure outcomes were better with perampanel as an early-line treatment than as a late-line treatment. TEAEs were reported by 48 patients (48.0%), most commonly dizziness (n = 9), fatigue (n = 7), and irritability (n = 7). Sixteen patients (16.0%) withdrew from perampanel treatment due to TEAEs.

SIGNIFICANCE

The interim analysis of PERPRISE offers insight into the real-world use of perampanel in Germany, including for the first time, clinical practice data from patients with GTCS and switching ASMs within a dual therapy. Further data from PERPRISE will be of value to inform clinical decision-making in this patient cohort.

PLAIN LANGUAGE SUMMARY

Patients with epilepsy often take more than one medication for seizure control. This 12month study looked at patients in Germany receiving perampanel as only add-on medication. The interim analysis shows, that at 6 months, over 70% of the 100 patients continued to use perampanel; 59% experienced no seizures during treatment with perampanel, and in 83%, seizure frequency was reduced by half. Side effects occurred in 48% of patients (most commonly dizziness, fatigue, and irritability) and caused 16% to withdraw from the study. Overall, perampanel was a suitable as only add-on medication for patients with epilepsy.

Diagnostic Value of Intermittent Photic Stimulation Among Adult Patients in a Tertiary Referral Epilepsy Center: A Retrospective Study

PURPOSE

Photosensitivity is a phenomenon that may be elicited by standardized intermittent photic stimulation during EEG recording and is detected more frequently in children and adolescents. Nevertheless, at our Epilepsy Center, we routinely assess photosensitivity in all newly referred adult patients. In this investigation, we sought to address the diagnostic yield under the prerequisites described.

METHODS

We reanalyzed all routine EEG recordings among referrals to the department of adults during the first six months of 2019, including a simultaneous video that is always coregistered in our center. The prevalence of abnormal findings during photic stimulation was assessed.

RESULTS

Intermittent photic stimulation was performed on 344 patients. Photoparoxysmal response were detected in five subjects (1.5%). All patients were female. Four patients were diagnosed with idiopathic generalized epilepsy, and one with Doose syndrome. Photomyogenic responses were recorded in 1.1% and only in patients with psychogenic nonepileptic seizures. In two subjects with psychogenic nonepileptic seizures, the typical seizure was provoked by intermittent photic stimulation (8.7% of all subjects with psychogenic nonepileptic seizures in this cohort). Photoparoxysmal response was not detected in any subject with focal epilepsy, syncope, or other nonepileptic paroxysmal events. In every case of photoparoxysmal responses, increased photosensitivity had already been reported before recording.

CONCLUSIONS

In our study, photoparoxysmal responses was a rare phenomenon among adults with a preponderance of females and idiopathic generalized epilepsies. Intermittent photic stimulation may be helpful in provoking typical psychogenic nonepileptic seizures and thus abbreviate the diagnostic process. Provided a careful history, routine intermittent photic stimulation in adults with epilepsy does not appear to be mandatory.

GWAS meta-analysis of over 29,000 people with epilepsy identifies 26 risk loci and subtype-specific genetic architecture

Epilepsy is a highly heritable disorder affecting over 50 million people worldwide, of which about one-third are resistant to current treatments. Here we report a multi-ancestry genome-wide association study including 29,944 cases, stratified into three broad categories and seven subtypes of epilepsy, and 52,538 controls. We identify 26 genome-wide significant loci, 19 of which are specific to genetic generalized epilepsy (GGE). We implicate 29 likely causal genes underlying these 26 loci. SNP-based heritability analyses show that common variants explain between 39.6% and 90% of genetic risk for GGE and its subtypes. Subtype analysis revealed markedly different genetic architectures between focal and generalized epilepsies. Gene-set analyses of GGE signals implicate synaptic processes in both excitatory and inhibitory neurons in the brain. Prioritized candidate genes overlap with monogenic epilepsy genes and with targets of current antiseizure medications. Finally, we leverage our results to identify alternate drugs with predicted efficacy if repurposed for epilepsy treatment.

Effectiveness and Tolerability of 12-Month Brivaracetam in the Real World: EXPERIENCE, an International Pooled Analysis of Individual Patient Records

BACKGROUND AND OBJECTIVE

Real-world evidence studies of brivaracetam (BRV) have been restricted in scope, location, and patient numbers. The objective of this pooled analysis was to assess effectiveness and tolerability of brivaracetam (BRV) in routine practice in a large international population.

METHODS

EXPERIENCE/EPD332 was a pooled analysis of individual patient records from multiple independent non-interventional studies of patients with epilepsy initiating BRV in Australia, Europe, and the United States. Eligible study cohorts were identified via a literature review and engagement with country lead investigators, clinical experts, and local UCB Pharma scientific/medical teams. Included patients initiated BRV no earlier than January 2016 and no later than December 2019, and had ≥ 6 months of follow-up data. The databases for each cohort were reformatted and standardised to ensure information collected was consistent. Outcomes included ≥ 50% reduction from baseline in seizure frequency, seizure freedom (no seizures within 3 months before timepoint), continuous seizure freedom (no seizures from baseline), BRV discontinuation, and treatment-emergent adverse events (TEAEs) at 3, 6, and 12 months. Patients with missing data after BRV discontinuation were considered non-responders/not seizure free. Analyses were performed for all adult patients (≥ 16 years), and for subgroups by seizure type recorded at baseline; by number of prior antiseizure medications (ASMs) at index; by use of BRV as monotherapy versus polytherapy at index; for patients who switched from levetiracetam to BRV versus patients who switched from other ASMs to BRV; and for patients with focal-onset seizures and a BRV dose of ≤ 200 mg/day used as add-on at index. Analysis populations included the full analysis set (FAS; all patients who received at least one BRV dose and had seizure type and age documented at baseline) and the modified FAS (all FAS patients who had at least one seizure recorded during baseline). The FAS was used for all outcomes other than ≥ 50% seizure reduction. All outcomes were summarised using descriptive statistics.

RESULTS

Analyses included 1644 adults. At baseline, 72.0% were 16-49 years of age and 92.2% had focal-onset seizures. Patients had a median (Q1, Q3) of 5.0 (2.0, 8.0) prior antiseizure medications at index. At 3, 6, and 12 months, respectively, ≥ 50% seizure reduction was achieved by 32.1% (n = 619), 36.7% (n = 867), and 36.9% (n = 822) of patients; seizure freedom rates were 22.4% (n = 923), 17.9% (n = 1165), and 14.9% (n = 1111); and continuous seizure freedom rates were 22.4% (n = 923), 15.7% (n = 1165), and 11.7% (n = 1111). During the whole study follow-up, 551/1639 (33.6%) patients discontinued BRV. TEAEs since prior visit were reported in 25.6% (n = 1542), 14.2% (n = 1376), and 9.3% (n = 1232) of patients at 3, 6, and 12 months, respectively.

CONCLUSIONS

This pooled analysis using data from a variety of real-world settings suggests BRV is effective and well tolerated in routine clinical practice in a highly drug-resistant patient population.

Failure to use new breakthrough treatments for epilepsy

Despite the approval of ~20 additional antiseizure medications (ASMs) since the 1980s, one-third of epilepsy patients experience seizures despite therapy. Drug-resistant epilepsy (DRE) is associated with cognitive and psychiatric comorbidities, socioeconomic impairment, injuries, and a 9.3-13.4 times higher mortality rate than in seizure-free patients. Improved seizure control can reduce morbidity and mortality. Two new ASMs were launched in the United States in 2020: cenobamate for focal epilepsy in adults and fenfluramine for Dravet syndrome (DS). They offer markedly improved efficacy. Cenobamate achieved 21% seizure freedom with the highest dose and decreased tonic-clonic seizures by 93% during maintenance treatment in a randomized clinical trial (RCT). In long-term, open-label studies, 10%-36% of patients were seizure-free for a median duration of ~30-45 months. Fenfluramine treatment in DS reduced convulsive seizure frequency by 56% over placebo at the highest dose, with 8% of patients free of convulsive seizures, and 25% with only one convulsive seizure over 14 weeks. These results were sustained for up to 3 years in open-label extension studies. Mortality was reduced 5-fold. These results are superior to all other approved ASMs, placing these two drugs among the most effective antiseizure therapies. The adverse event profiles resemble those of other ASMs. Despite greater efficacy and similar toxicity, these medications are infrequently used. Two years after US market entry, < 5% of either adults with focal DRE or patients with DS were treated with either cenobamate or fenfluramine. We believe this is a failure of our medical system, resulting from limited knowledge about these drugs stemming partly from the separation of academia from industry; restrictions to access created by health care payors, hospitals, and regulatory agencies; and insufficient post-launch information about the efficacy and safety of these ASMs.

Real-world data on cannabidiol treatment of various epilepsy subtypes: A retrospective, multicenter study

OBJECTIVE

Cannabidiol (CBD) is approved for treatment of Dravet syndrome (DS), Lennox-Gastaut syndrome (LGS), and tuberous sclerosis complex (TSC). Several studies suggest antiseizure effects also beyond these three epilepsy syndromes.

METHODS

In a retrospective multicenter study, we analyzed the efficacy and tolerability of CBD in patients with epilepsy at 16 epilepsy centers.

RESULTS

The study cohort comprised 311 patients with epilepsy with a median age of 11.3 (0-72) years (235 children and adolescents, 76 adults). Therapy with CBD was off-label in 91.3% of cases due to age, epilepsy subtype, lack of adjunct therapy with clobazam, and/or higher dose applied. CBD titration regimens were slower than recommended, with good tolerability of higher doses particularly in children. Of all patients, 36.9% experienced a reduction in seizure frequency of >50%, independent of their epilepsy subtype or clobazam co-medication. The median observation period was 15.8 months. About one third of all patients discontinued therapy within the observation period due to adverse effects or lack of efficacy. Adverse effects were reported frequently (46.9%).

SIGNIFICANCE

Our study highlights that CBD has an antiseizure effect comparable to other antiseizure medications with a positive safety profile independent of the epilepsy subtype. Comedication with clobazam was not associated with a better outcome. Higher doses to achieve seizure frequency reduction were safe, particularly in children. These findings call for further trials for an extended approval of CBD for other epilepsy subtypes and for children <2 years of age.

Loss-of-function variants in the KCNQ5 gene are implicated in genetic generalized epilepsies

Background

De novo missense variants in KCNQ5, encoding the voltage-gated K⁺ channel K_V7.5, have been described to cause developmental and epileptic encephalopathy (DEE) or intellectual disability (ID). We set out to identify disease-related KCNQ5 variants in genetic generalized epilepsy (GGE) and their underlying mechanisms.

Methods

1292 families with GGE were studied by next-generation sequencing. Whole-cell patch-clamp recordings, biotinylation and phospholipid overlay assays were performed in mammalian cells combined with homology modelling.

Findings

We identified three deleterious heterozygous missense variants, one truncation and one splice site alteration in five independent families with GGE with predominant absence seizures; two variants were also associated with mild to moderate ID. All missense variants displayed a strongly decreased current density indicating a loss-of-function (LOF). When mutant channels were co-expressed with wild-type (WT) K_V7.5 or K_V7.5 and K_V7.3 channels, three variants also revealed a significant dominant-negative effect on WT channels. Other gating parameters were unchanged. Biotinylation assays indicated a normal surface expression of the variants. The R359C variant altered PI(4,5)P₂-interaction.

Interpretation

Our study identified deleterious KCNQ5 variants in GGE, partially combined with mild to moderate ID. The disease mechanism is a LOF partially with dominant-negative effects through functional deficits. LOF of K_V7.5 channels will reduce the M-current, likely resulting in increased excitability of K_V7.5-expressing neurons. Further studies on network level are necessary to understand which circuits are affected and how this induces generalized seizures.

Funding

DFG/FNR Research Unit FOR-2715 (Germany/Luxemburg), BMBF rare disease network Treat-ION (Germany), foundation ‘no epilep’ (Germany).

Long-term Efficacy and Safety From an Open-Label Extension of Adjunctive Cenobamate in Patients With Uncontrolled Focal Seizures

BACKGROUND AND OBJECTIVES

To evaluate long-term efficacy (percent seizure frequency reduction and responder rates), safety, and tolerability of adjunctive cenobamate (CNB) in an open-label extension (OLE) of the randomized, double-blind, placebo-controlled study.

METHODS

Patients (aged 18-70 years) with uncontrolled focal seizures despite treatment with 1-3 antiseizure medications who completed the 18-week double-blind study (n = 360) could enter the OLE, where they underwent a 2-week blinded conversion to CNB (target dose, 300 mg/d; min/max, 50/400 mg/d).

RESULTS

Three hundred fifty-five patients were included in the OLE safety population (265 originally randomized to CNB, 90 originally randomized to placebo), and 354 were included in the OLE modified intent-to-treat population. As of July 2019, 58.9% of patients (209/355) were continuing CNB treatment and 141 had discontinued, including 16.6% (59/355) because of lack of efficacy, 8.7% (31/355) because of withdrawal by patient, and 7.6% (27/355) because of adverse events. The median (range) duration of OLE exposure was 53.9 (1.1-68.7) months. Retention rates at 12, 24, 36, and 48 months were 83%, 71%, 65%, and 62%, respectively. Median percent seizure frequency reduction over baseline increased with each 6-month OLE interval, up to 76.1% at months 43-48. Among observed patients, 16.4% (36/220) achieved 100% and 39.1% (86/220) achieved ≥90% seizure reduction during >36-48 months. Among the initial OLE modified intent-to-treat population, 10.2% of patients (36/354) achieved 100% and 24.3% (86/354) achieved ≥90% seizure reduction during >36-48 months. Similar to the double-blind study, adverse events (AEs) included dizziness, somnolence, fatigue, and headache. Serious AEs occurred in 20.3% of patients (72/355).

DISCUSSION

Long-term efficacy, including 100% and ≥90% seizure reduction, was sustained during 48 months of CNB treatment, with 71% retention at 24 months. No new safety issues were identified. These results confirm the findings of the double-blind study and support the potential long-term clinical benefit of CNB.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that oral CNB 50-400 mg/d is effective as an adjunctive treatment for the long-term management of patients with uncontrolled focal seizures previously treated with 1-3 ASMs.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov NCT01866111 (clinicaltrials.gov/ct2/show/results/NCT01866111).

Onset of efficacy and adverse events during Cenobamate titration period

OBJECTIVES

Cenobamate is an antiseizure medication (ASM) approved in Europe as adjunctive therapy for adults with inadequately controlled focal seizures. This post hoc analysis reports onset of efficacy and characterizes time to onset, duration, and severity of the most common treatment-emergent adverse events (TEAEs) during cenobamate titration.

MATERIALS & METHODS

Adult patients with uncontrolled focal seizures taking 1 to 3 concomitant ASMs were randomized to receive adjunctive cenobamate or placebo (double-blind studies C013 and C017) or cenobamate (open-label study C021). Outcome assessments included efficacy (median percentage change in seizure frequency and onset [studies C013 and C017]) and safety (onset, duration, and severity of TEAEs [all studies]).

RESULTS

Onset of efficacy was observed by Weeks 1 to 4 of titration in studies C013 and C017 which used a faster titration schedule than study CO21. In study C013, the median percentage seizure frequency reduction was 36.7% in patients receiving cenobamate versus 16.3% in those taking placebo (p = .002); in study C017, significant differences in seizure frequency emerged in Week 1 and continued throughout titration between all cenobamate groups and placebo (p < .001). The most commonly reported TEAEs were somnolence, dizziness, fatigue, and headache, with first onset of each reported as early as Week 1; however, the majority resolved.

CONCLUSIONS

Reductions in seizure frequency occurred during titration with initial efficacy observed prior to reaching the target dose. These reductions were regarded as clinically meaningful because they may indicate early efficacy at lower doses than previously expected and had a considerable impact on patient quality of life. Long-term treatment with adjunctive cenobamate was generally safe and well-tolerated.

163 Long-term safety of adjunctive cenobamate in patients with uncontrolled focal seizures

Purpose

Results from two double-blind, placebo-controlled studies demonstrated that adjunctive ceno- bamate significantly reduced the frequency of seizures vs placebo. Cenobamate 200mg/day achieved seizure freedom in 28.3% vs 8.8% placebo (P<0.0003; 013 study maintenance phase) and 21.1%, 11.2% for cenobamate 400mg/d and 200mg/d, respectively, vs 1% in placebo (P<0.002; 017 maintenance phase). Cenobamate also showed a favorable safety and tolerability profile. Here, we report the combined long-term safety and tolerability outcomes from the ongoing open-label extensions (OLEs) of C013 and C017.

Methods

Adults with uncontrolled FOS were enrolled in two double-blind, placebo-controlled studies. Patients completing both double-blinded phases were invited to participate in OLE studies (n=504).

Results

As of July 2019, 58.3% of the patients who entered the OLEs, continued; at baseline, median age was 38 years, and 86.5% were taking ≥2 concomitant AEDs. Median (range) length of exposure was 237 weeks (1–407). The most frequent TEAEs (≥10%) were dizziness (33.9%), somnolence (23.6%), headache (18.7%), fatigue (14.3%), diplopia (12.9%) and upper respiratory tract infections (12.3%). Most TEAEs were mild or moderate (78%). 22% experienced SAEs of which only seizure exceeded 1% (n=11). Discontinu- ations were due to TEAE (8%), withdrawal by patient (12%), lack of efficacy (12%), other (4%). No cases of DRESS were reported.

Conclusions

Long-term adjunctive cenobamate treatment (up to 94 months) is generally well tolerated. Most TEAEs were CNS-related and consistent with those shown in the two double-blind studies.

lee.finlan@arvelletx.com

157 Efficacy of adjunctive cenobamate: post-hoc analysis in patients grouped by concomitant anti-epileptic drug type

Purpose

There has been little success with polytherapy for patients with drug-resistant epilepsy. The need for optimizing AED combinations is high. Cenobamate is a novel AED with a unique, dual, complementary mechanism of action (MoA) combining GABA-A positive allosteric modulation (via a binding site different from benzodiazepines) together with broad spectrum sodium channel blockage. Here we assessed the efficacy of cenobamate when combined with AEDs grouped by MoA.

Methods

A post-hoc exploratory analysis of the study C017, in adult epilepsy patients with uncontrolled focal onset seizures who had ≥4 seizures/month despite treatment with stable doses of 1–3 AEDs.

Results

In the maintenance phase, 183/397 (46%) patients were receiving at least one GABA modulator (felbamate, valproate, topiramate, tiagabine, vigabatrin) and 329/397 (82%) a sodium channel blockers (carbamazepine, oxcarbazepine, lamotrigine, lacosamide, eslicarbazepine). Added onto GABA modu- lators, cenobamate 100/200/400mg achieved seizure freedom rates (SFR) of 7.3%/15.6%/30.6% vs 2.1% for placebo; when added onto sodium channel blockers, cenobamate 100/200/400mg/day showed SFR of 2.3%/9.3%/17.5% vs 1.2% for placebo. Both results were statistically significant for 200 and 400mg. A consistent SFR with cenobamate for a subset of patients receiving background levetiracetam (11% 200mg and 25% 400 mg vs 2.5% placebo) as well as those with background benzodiazepines (20% 400 mg vs 0% placebo) occurred.

Conclusions

Adjunctive cenobamate achieved significant dose-dependent SFR when combined with AEDs across multiple MoAs in patients with uncontrolled FOS.

lee.finlan@arvelletx.com

Long-term individual retention with cenobamate in adults with focal seizures: Pooled data from the clinical development program

Objective

We determined retention on open‐label cenobamate therapy in the clinical development program to assess the long‐term efficacy and tolerability of adjunctive cenobamate in individuals with uncontrolled focal seizures.

Methods

Data from two randomized, controlled cenobamate studies and one open‐label safety and pharmacokinetic study were pooled. Based on the percentage of participants remaining on treatment, retention rates were estimated using Kaplan‐Meier survival analyses. We performed two additional analyses to assess factors contributing to retention, stratifying a robust data set (through 2 years) by cenobamate modal dose and frequently used concomitant anti‐seizure medications. Cenobamate discontinuations and treatment‐emergent adverse events were summarized.

Results

Data from 1844 participants were pooled: 149 from a single‐dose randomized trial, 355 from a multi‐dose randomized trial, and 1340 from an open‐label safety and pharmacokinetic study. Most participants from randomized trials continued in open‐label extensions, and pooled data represent >95% of participants exposed to cenobamate. Baseline characteristics and disease and treatment histories were similar across studies. Median duration of cenobamate exposure was 34 months, with a median modal dose of 200 mg/day. Kaplan‐Meier estimates of cumulative cenobamate retention rates were 80% at 1 year and 72% at 2 years. Once participants reached the maintenance phase, retention rates were consistently high in participants receiving ≥100 mg/day cenobamate, and concomitant anti‐seizure medications did not affect long‐term retention. By 2 years, 535 (29%) had actually discontinued cenobamate; the most common reasons for discontinuation were adverse events (37.6%), withdrawal of consent (21.1%), and other (16.8%).

Significance

Treatment retention rates provide a proxy measure for long‐term efficacy, safety, tolerability, and adherence. The consistently high retention rates we found suggest that cenobamate may be an effective and well‐tolerated new treatment option for people with drug‐resistant focal seizures.

Practical guidance for the management of adults receiving adjunctive cenobamate for the treatment of focal epilepsy-expert opinion

Clinical trial results have demonstrated that adjunctive cenobamate (CNB) substantially decreases seizure frequency in adults with uncontrolled focal onset seizures with an acceptable and well-identified safety profile. This manuscript summarizes an expert panel's recommendations regarding optimized CNB treatment of epilepsies with focal onset seizures. Cenobamate, when slowly titrated to the target maintenance dose, represents an effective new antiseizure medication (ASM) with a comparatively high rate of seizure freedom relative to existing treatment options. This paper reviews selection of suitable CNB treatment candidates, realistic treatment expectations and goals, appropriate CNB target doses, and methods to mitigate or avoid potential adverse events. Cenobamate can be a promising therapeutic choice for adult people with epilepsy with focal onset seizures who do not reach adequate seizure control despite treatment with conventional ASMs.

[SUDEP in brief - knowledge and practice recommendations on sudden unexpected death in epilepsy]

Sudden unexpected death in epilepsy (SUDEP) is the sudden and unexpected death of an epilepsy patient, which occurs under benign circumstances without evidence of typical causes of death. SUDEP concerns all epilepsy patients. The individual risk depends on the characteristics of the epilepsy and seizures as well as on living conditions. Focal to bilateral and generalized tonic-clonic seizures (TCS), nocturnal seizures and lack of nocturnal supervision increase the risk. Most SUDEP cases are due to a fatal cascade of apnea, hypoxemia and asystole in the aftermath of a TCS. Two thirds of SUDEP cases in unsupervised epilepsy patients with TCS could probably be prevented. Wearables can detect TCS and alert caregivers. SUDEP information is desired by most patients and relatives, has a favorable impact on treatment adherence and behavior and has no negative effects on mood and quality of life.Recommendations of the committee on patient safety of the German Society of Epileptology: the ultimate treatment goal is seizure freedom. If this cannot be achieved, control of TCS should be sought. All epilepsy patients and their relatives should be informed about SUDEP and risk factors. Patients and relatives should be informed about measures to counteract the elevated risk and imminent SUDEP. The counselling should be performed during a face-to-face discussion, at the time of first diagnosis or during follow-up visits. The counselling should be documented. Wearables for TCS detection can be recommended. If TCS persist, therapeutic efforts should be continued. The bereaved should be contacted after a SUDEP.

Behavioral adverse events with brivaracetam, levetiracetam, perampanel, and topiramate: A systematic review

PURPOSE

To understand the currently available post-marketing real-world evidence of the incidences of and discontinuations due to the BAEs of irritability, anger, and aggression in people with epilepsy (PWE) treated with the anti-seizure medications (ASMs) brivaracetam (BRV), levetiracetam (LEV), perampanel (PER), and topiramate (TPM), as well as behavioral adverse events (BAEs) in PWE switching from LEV to BRV.

METHODS

A systematic review of published literature using the Cochrane Library, PubMed/MEDLINE, and Embase was performed to identify retrospective and prospective observational studies reporting the incidence of irritability, anger, or aggression with BRV, LEV, PER, or TPM in PWE. The incidences of these BAEs and the rates of discontinuation due to each were categorized by ASM, and where possible, weighted means were calculated but not statistically assessed. Behavioral and psychiatric adverse events in PWE switching from LEV to BRV were summarized descriptively.

RESULTS

A total of 1500 records were identified in the searches. Of these, 44 published articles reporting 42 studies met the study criteria and were included in the data synthesis, 7 studies were identified in the clinical trial database, and 5 studies included PWE switching from LEV to BRV. Studies included a variety of methods, study populations, and definitions of BAEs. While a wide range of results was reported across studies, weighted mean incidences were 5.6% for BRV, 9.9% for LEV, 12.3% for PER, and 3.1% for TPM for irritability; 3.3%* for BRV, 2.5% for LEV, 2.0% for PER, and 0.2%* for TPM for anger; and 2.5% for BRV, 2.6% for LEV, 4.4% for PER, and 0.5%* for TPM for aggression. Weighted mean discontinuation rates were 0.8%* for BRV, 3.4% for LEV, 3.0% for PER, and 2.2% for TPM for irritability and 0.8%* for BRV, 2.4% for LEV, 9.2% for PER, and 1.2%* for TPM for aggression. There were no discontinuations for anger. Switching from LEV to BRV led to improvement in BAEs in 33.3% to 83.0% of patients (weighted mean, 66.6%). *Denotes only 1 study.

CONCLUSIONS

This systematic review characterizes the incidences of irritability, anger, and aggression with BRV, LEV, PER, and TPM, and it provides robust real-world evidence demonstrating that switching from LEV to BRV may improve BAEs. While additional data remain valuable due to differences in methodology (which make comparisons difficult), these results improve understanding of the real-world incidences of discontinuations due to these BAEs in clinical practice and can aid in discussions and treatment decision-making with PWE.

Epilepsy surgery: Late seizure recurrence after initial complete seizure freedom

OBJECTIVE

This study was undertaken to improve understanding of late relapse following epilepsy surgery in pharmacoresistant epilepsy.

METHODS

Retrospective comparison was made of 99 of 1278 patients undergoing surgery during 1999-2015 with seizure relapses after at least 2 years of complete seizure freedom with matched controls experiencing continued long-term seizure freedom. Univariate and multivariate analyses were performed.

RESULTS

With a mean follow-up of 9.7 years, mean time to seizure relapse was 56.6 months. In multivariate analysis, incomplete resection based on magnetic resonance imaging (MRI), bilateral lesions on preoperative MRI, and epilepsy onset in the first year of life carried a significantly higher risk of late relapse. In patients with late relapse, additional functional imaging with positron emission tomography had been performed significantly more often. Although the differences were not significant in multivariate analysis, doses of antiepileptic drugs were higher in the relapse group preoperatively and in the first 24 months and complete withdrawal was more frequent in the control group (68% vs. 51%). Regarding seizure frequency, most patients had mild seizure relapse (single relapse seizure or <1/month).

SIGNIFICANCE

In our predominantly lesional cohort, complete resection of the MRI lesion is the most important factor to maintain long-term seizure freedom. Two patterns of recurrence were identified: (1) incomplete resected lesions with seizure generation in proximity to the initial resection and (2) epileptogenic networks not detected preoperatively or evolving in the postoperative interval and manifesting with new clinical and diagnostic features.

Status of clinical research in neurology in Germany-A national survey

BACKGROUND AND PURPOSE

To provide an overview on the status of clinical research in neurology in Germany.

METHODS

German university hospitals, nonuniversity hospitals, and neurological medical practices were surveyed regarding their clinical research activities during the period 2013 to 2017.

RESULTS

Fifty percent of university hospitals, 10.6% of nonuniversity hospitals, and 5.2% of medical practices in Germany responded to our questionnaire. More than 80% of the clinical studies conducted have been phase III/IV and noninterventional trials (NISs), whereas <1% have been phase I and 3.5% investigator-initiated trials (IITs). University hospitals have conducted most of the phase II-IV trials. NISs have been predominantly performed by medical practices. Fifty-six percent of the university hospitals and less of the nonuniversity institutions confirmed the implementation of standard operating procedures (SOPs). In university hospitals, on average, 11 physicians had acquired a good clinical practice certificate. Overall, 43% of all trials have been performed in neuroimmunology.

CONCLUSIONS

The status of clinical research in neurology in Germany is predominated by NISs and late-phase trials, potentially due to a general lack of easily accessible funding, which leads to a highly competitive environment and fewer opportunities to perform early-phase clinical trials as well as IITs. Our results indicate that there is substantial need for structured support for creating and implementing SOPs to maintain quality standards and guarantee uniformity of performance. This survey assessed many aspects of clinical research and serves as guidance for providing ideas for structured improvement of clinical research in neurology in Germany.

Everolimus in adult tuberous sclerosis complex patients with epilepsy: Too late for success? A retrospective study

OBJECTIVE

There is evidence that everolimus (EVE) significantly reduces seizure frequency in epilepsy patients with tuberous sclerosis complex (TSC). Given that TSC-related proliferative processes are more dynamic during brain development, seizure outcomes of patients treated with EVE may be age-related and may be less convincing in adult patients. The aim of this study was to assess the effectiveness and the safety profile of EVE in adults in clinical practice.

METHODS

We performed a multicenter retrospective chart review of TSC subjects with active epilepsy who started EVE in adulthood (≥18 years of age) at seven German epilepsy centers. The primary endpoint was the retention rate after 6 months.

RESULTS

A total of 45 subjects with a mean age of 31.6 ± 11.1 years at EVE start fulfilled the inclusion criteria. Retention rate after 6 months was 98% (43/44 evaluable subjects). Response rate (seizure reduction ≥ 50%) was 33% (14/43 evaluable subjects; four completely seizure-free). We did not find a significant relationship between epilepsy outcome parameters and patient age at EVE start. Adverse events were reported in 19 subjects and were judged to be serious in six patients. Three patients died during the observation period.

SIGNIFICANCE

Evidence suggests that EVE is an effective add-on treatment for epilepsy in adult TSC patients, surprisingly without any age limit to individual benefit. A strong age-dependent effect within the period of adulthood seems unlikely. Even if there was no proof of a causal relationship between deaths and EVE intake, patients with EVE should be carefully monitored, especially for infections and stomatitis.

Cenobamate tablets as a treatment for focal-onset seizures in adults

Introduction: Despite the introduction of numerous new antiseizure medications (ASMs) still about one-third of epilepsies remain drug-resistant. Therefore, new compounds with advanced efficacy are urgently needed. Cenobamate (CNB) is a new ASM that has been recently introduced in the United States for the treatment of adults with focal-onset seizures. The approval in Europe is under way.Areas covered: This review covers the pharmacological profile of CNB, the proof-of-concept trial, the two double-blind, placebo-controlled phase 2 trials investigating adjunct CNB in adults with focal-onset seizures, one open-label safety trial, and a variety of published abstract material that provided additional post hoc data.Expert opinion: In two placebo-controlled randomized multicenter phase 2 trials adjunct CNB showed unusually high efficacy with rates of seizure-free people with epilepsy (PWE) partially beyond 20%. However, during the clinical program cases of drug-related reactions with eosinophilia and systemic symptoms (DRESS syndrome) occurred. Therefore, an open-label safety study was performed in more than 1300 PWE with particularly slower titration schedules which did not add more cases with similar reactions. Taking into consideration the promising efficacy and the safety experience from the open-label trial, CNB applied according to the meanwhile recommended titration strategy, might offer a new prospect.

Is the anticonvulsant activity of levetiracetam dose-dependent?

PURPOSE

Although levetiracetam (LEV) is globally established as a leading antiseizure medication (ASM) it is still a controversial matter whether dose increases correspond with an increased efficacy if LEV in the recommended dose range did not show satisfying efficacy. In our clinical perception we questioned the value of dose increases in such non-responders.

METHODS

In this retrospective monocenter study we analyzed the data of adult people with epilepsies (PWE) with focal-onset seizures who had been treated at the department of adults of the Kork Epilepsy Center between 2009 and 2019, who had been on a stable daily LEV dose and in whom LEV was further increased due to further seizures in spite of baseline LEV in a recommended daily dose range. For reasons of data homogeneity, we included only PWE with at least two definite seizures during the hospital stay under the baseline LEV dose who were treated and observed as in-patients after the increase of LEV for a period at least three-fold longer than the baseline interval before. Additional data acquisition comprised clinical data including adverse events, serum concentrations of LEV and other ASMs, and additional laboratory findings. The primary outcome variable was the change of seizure frequency prior to and after the increase of LEV.

RESULTS

Out of 518 PWE who had been on LEV during their hospital stay, a total of 61 PWE fulfilled the inclusion criteria. After a gradual dose increment, 91,8 % of PWE showed a reduced seizure frequency, 73,8 % had a reduction of seizures of 50 % or more, and 21,3 % were seizure-free during the observation period. A significant seizure reduction could be shown with a seizure count of 2,5/week prior to the increment and 0,7/week after dose increment (p < 0,00001). Seven PWE reported minor adverse events and ten PWE showed slight laboratory changes (within normal levels).

CONCLUSION

Contrary to our long-term clinical impression, LEV dose increments were reasonable and improved the seizure situation in PWE, usually without additional safety hazards.

Padsevonil randomized Phase IIa trial in treatment-resistant focal epilepsy: a translational approach

Therapeutic options for patients with treatment-resistant epilepsy represent an important unmet need. Addressing this unmet need was the main factor driving the drug discovery program that led to the synthesis of padsevonil, a first-in-class antiepileptic drug candidate that interacts with two therapeutic targets: synaptic vesicle protein 2 and GABA_A receptors. Two PET imaging studies were conducted in healthy volunteers to identify optimal padsevonil target occupancy corresponding to levels associated with effective antiseizure activity in rodent models. Optimal padsevonil occupancy associated with non-clinical efficacy was translatable to humans for both molecular targets: high (>90%), sustained synaptic vesicle protein 2A occupancy and 10-15% transient GABA_A receptor occupancy. Rational dose selection enabled clinical evaluation of padsevonil in a Phase IIa proof-of-concept trial (NCT02495844), with a single-dose arm (400 mg bid). Adults with highly treatment-resistant epilepsy, who were experiencing ≥4 focal seizures/week, and had failed to respond to ≥4 antiepileptic drugs, were randomized to receive placebo or padsevonil as add-on to their stable regimen. After a 3-week inpatient double-blind period, all patients received padsevonil during an 8-week outpatient open-label period. The primary endpoint was ≥75% reduction in seizure frequency. Of 55 patients randomized, 50 completed the trial (placebo n = 26; padsevonil n = 24). Their median age was 36 years (range 18-60), and they had been living with epilepsy for an average of 25 years. They were experiencing a median of 10 seizures/week and 75% had failed ≥8 antiepileptic drugs. At the end of the inpatient period, 30.8% of patients on padsevonil and 11.1% on placebo were ≥75% responders (odds ratio 4.14; P = 0.067). Reduction in median weekly seizure frequency was 53.7% and 12.5% with padsevonil and placebo, respectively (unadjusted P = 0.026). At the end of the outpatient period, 31.4% were ≥75% responders and reduction in median seizure frequency was 55.2% (all patients). During the inpatient period, 63.0% of patients on placebo and 85.7% on padsevonil reported treatment-emergent adverse events. Overall, 50 (90.9%) patients who received padsevonil reported treatment-emergent adverse events, most frequently somnolence (45.5%), dizziness (43.6%) and headache (25.5%); only one patient discontinued due to a treatment-emergent adverse event. Padsevonil was associated with a favourable safety profile and displayed clinically meaningful efficacy in patients with treatment-resistant epilepsy. The novel translational approach and the innovative proof-of-concept trial design maximized signal detection in a small patient population in a short duration, expediting antiepileptic drug development for the population with the greatest unmet need in epilepsy.

Visual illustration supporting patient-physician communication in epilepsy: A validation and reliability study of seizure images

Seizure manifestations may be difficult to describe in words alone. Thus, initially, 24 seizure images were developed to support communication and gain assistance during obtaining the patient's history. Before being used in clinical practice, these seizure images must be investigated for validity and reliability. We tested the images with untrained participants including patients with epilepsy, persons who had witnessed seizures, and participants who had neither had nor witnessed epileptic seizures. The participants filled in a questionnaire evaluating the images twice within 3 days. The participants were asked to choose one of the 2 written descriptions that best matched each seizure image. The validity was assessed using one-proportion z-test. The reliability was assessed by Gwet's AC1. The first analysis showed that the proportion of correctly identified seizure images was higher than 70%, except for 2 images representing dystonia and myoclonus. The dystonia image was modified, and the myoclonus image was removed. In the final evaluation, the seizure images were identified with an overall correctness ratio of 96%. The final AC1 of the seizure images was classified as very high. The final 23 seizure images are proved to be valid and have a high agreement that can be used in clinical practice.

[Cenobamate-a new perspective for epilepsy treatment]

In spite of the introduction of numerous new antiseizure drugs (ASD) over the last decades, the percentage of drug-resistant epilepsies has remained almost stable. To achieve seizure freedom in such patients with any modified ASD regimen is an exception. Cenobamate (CNB) is a new ASD that showed unusually high efficacy in the pivotal placebo controlled, randomized trials. In both studies (C013 and C017), the rate of seizure-free patients was sometimes more than 20% and thus in a range never reached over the last decades in comparable trials with other new ASDs. This suggests that CNB which is already approved in the USA might actually offer a new and encouraging perspective for epilepsy treatment concerning efficacy. In this review the pharmacological profile, the currently known mode of action, and the results of the clinical trials are summarized.

Alterations of intracerebral connectivity in epilepsy patients with secondary bilateral synchrony

INTRODUCTION

The aim of our study was to evaluate intracerebral network changes in epilepsy patients demonstrating secondary bilateral synchrony (SBS) in EEG by applying a new Diffusion Tensor Imaging (DTI) method using an energy-based global tracking algorithm.

MATERIALS AND METHODS

10 MRI negative epilepsy patients demonstrating SBS in 10-20 surface EEG were included. EEG findings were analyzed for irritative zones characterized by focal interictal epileptiform discharges (IEDs) triggering SBS. In addition, DTI including an energy-based global tracking algorithm was applied to analyze fiber tract alterations in irritative zones. To measure the deviation of a certain cortical connection in comparison to healthy controls, normalized differences of fiber tract streamline counts (SC) and their p-values were evaluated in comparison to corresponding fibers of the control group.

RESULTS

In 6 patients the irritative zone initiating SBS was located in the frontal lobe, in 3 patients in the temporal lobe and in 1 patient in the region surrounding the right central sulcus. All patients demonstrated significantly altered SC in brain lobes where the irritative zone triggering SBS was located (p ≤ 0.05). Seven out of 10 patients demonstrated SC alterations in tracts connecting brain lobes between the ipsilateral and the contralateral hemisphere (p ≤ 0.05).

CONCLUSION

Our data demonstrate that alterations in fiber tracts in irritative zones triggering SBS are not necessarily associated with intracerebral lesions visible in high resolution MRI. Our study gives evidence that diffusion tensor imaging is a promising non-invasive additive tool for intracerebral network analyses even in MRI-negative epilepsy patients.

Adjunctive perampanel and myoclonic and absence seizures: Post hoc analysis of data from study 332 in patients with idiopathic generalized epilepsy

PURPOSE

This post hoc analysis assessed the effects of adjunctive perampanel on myoclonic and absence seizure outcomes in patients (aged ≥12 years) with idiopathic generalized epilepsy (IGE) and generalized tonic-clonic seizures during the double-blind (up to 8 mg/day) and open-label extension (OLEx; up to 12 mg/day) phases of Study 332.

METHODS

Patients experiencing myoclonic and/or absence seizures during study baseline were included. Assessments for myoclonic and absence seizures included: median percent change in seizure frequency, number of seizure days and seizure-free days (all per 28 days), 50 % and 75 % responder rates, seizure-freedom rates, seizure worsening, and monitoring of treatment-emergent adverse events (TEAEs).

RESULTS

During the double-blind phase, myoclonic and/or absence seizures were reported in 47/163 and 60/163 patients, respectively. Median percent reductions in seizure frequency per 28 days from study baseline were 52.5% and 24.5% (myoclonic seizures) and 7.6 % and 41.2 % (absence seizures) for placebo and perampanel, respectively; seizure-freedom rates were 13.0 % and 16.7 % (myoclonic seizures) and 12.1 % and 22.2 % (absence seizures), respectively. During the OLEx phase, 46/138 and 52/138 patients experienced myoclonic and/or absence seizures, respectively. Responses during the double-blind phase were maintained during long-term (>104 weeks) adjunctive perampanel treatment. The frequency/type of TEAEs was consistent with the known safety profile of perampanel.

CONCLUSION

In this post hoc analysis, adjunctive perampanel was not associated with any overall worsening of absence seizures. Further research is needed to investigate the effect of adjunctive perampanel in IGE patients with myoclonic and/or absence seizures.

Desynchronization of temporal lobe theta-band activity during effective anterior thalamus deep brain stimulation in epilepsy

BACKGROUND

Bilateral cyclic high frequency deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) reduces the seizure count in a subset of patients with epilepsy. Detecting stimulation-induced alterations of pathological brain networks may help to unravel the underlying physiological mechanisms related to effective stimulation delivery and optimize target engagement.

METHODS

We acquired 64-channel electroencephalography during ten ANT-DBS cycles (145 ​Hz, 90 ​μs, 3-5 ​V) of 1-min ON followed by 5-min OFF stimulation to detect changes in cortical activity related to seizure reduction. The study included 14 subjects (three responders, four non-responders, and seven healthy controls). Mixed-model ANOVA tests were used to compare differences in cortical activity between subgroups both ON and OFF stimulation, while investigating frequency-specific effects for the seizure onset zones.

RESULTS

ANT-DBS had a widespread desynchronization effect on cortical theta and alpha band activity in responders, but not in non-responders. Time domain analysis showed that the stimulation induced reduction in theta-band activity was temporally linked to the stimulation period. Moreover, stimulation induced theta-band desynchronization in the temporal lobe channels correlated significantly with the therapeutic response. Responders to ANT-DBS and healthy-controls had an overall lower level of theta-band activity compared to non-responders.

CONCLUSION

This study demonstrated that temporal lobe channel theta-band desynchronization may be a predictive physiological hallmark of therapeutic response to ANT-DBS and may be used to improve the functional precision of this intervention by verifying implantation sites, calibrating stimulation contacts, and possibly identifying treatment responders prior to implantation.

High-frequency electrical stimulation of the anterior thalamic nuclei increases vigilance in epilepsy patients during relaxed and drowsy wakefulness

OBJECTIVE

High-frequency deep brain stimulation (DBS) of anterior thalamic nuclei (ANT) reduces the frequency and intensity of focal and focal to bilateral tonic-clonic epileptic seizures. We investigated the impact of high-frequency ANT-DBS on vigilance in epilepsy patients during relaxed and drowsy wakefulness, to better understand the effects and the mechanisms of action of this intervention in humans.

METHODS

Four patients with different structural epileptic pathologies were included in this retrospective case-cohort study. Short- and long-term electroencephalography (EEG) was used to determine states of relaxed or drowsy wakefulness and the vigilance changes during stimulation-on and stimulation-off intervals.

RESULTS

In relaxed, wakeful patients with eyes closed, the eyelid artifact rate increased acutely and reproducibly during stimulation-on intervals, suggesting an enhanced vigilance. This effect was accompanied by a slight acceleration of the alpha rhythm. In drowsy patients with eyes closed, stimulation generated acutely and reproducibly alpha rhythms, similar to the paradoxical alpha activation during eyes opening. The occurrence of the alpha rhythms reflected an increase in the vigilance of the drowsy subjects during ANT-DBS.

SIGNIFICANCE

This is the first demonstration that ANT-DBS increases the vigilance of wakeful epilepsy patients. Our results deliver circumstantial evidence that high-frequency ANT-DBS activates thalamocortical connections that promote wakefulness.

Efficacy and safety of adjunctive perampanel 4 mg/d for the treatment of focal seizures: A pooled post hoc analysis of four randomized, double-blind, phase III studies

OBJECTIVE

This post hoc analysis evaluated the efficacy and safety of adjunctive perampanel 4 mg/d received as modal dose, which may have differed from randomized dose, for treatment of focal seizures.

METHODS

Data were pooled from four randomized, double-blind, placebo-controlled, phase III studies of adjunctive perampanel in patients (aged ≥12 years) with focal seizures, with/without focal to bilateral tonic-clonic (FBTC) seizures: studies 304 (NCT00699972), 305 (NCT00699582), 306 (NCT00700310), and 335 (NCT01618695). Efficacy assessments included median percentage reductions in seizure frequency per 28 days and seizure-freedom rates for patients receiving placebo and perampanel 4 mg/d (modal dose). Treatment-emergent adverse events (TEAEs) were assessed in patients receiving perampanel 4 mg/d at their TEAE onset. Outcomes were also assessed with/without enzyme-inducing antiseizure medications (EIASMs).

RESULTS

The full analysis set included 979 patients with focal seizures (placebo: n = 616 [235 with FBTC seizures]; perampanel 4 mg/d: n = 363 [134 with FBTC seizures]). Compared with placebo, perampanel 4 mg/d conferred significantly greater median percentage reductions in seizure frequency per 28 days for focal (12.6% vs 21.1%; P = .0004) and FBTC seizures (17.4% vs 49.8%; P < .0001), and seizure-freedom rates for focal (0.8% vs 3.6%; P = .0018) and FBTC seizures (11.1% vs 18.7%; P = .0424). Seizure improvements with perampanel 4 mg/d were greater without EIASMs than with EIASMs. For assessment of TEAEs, overall 1376 patients with focal seizures received perampanel 4 mg/d at any time (FBTC seizures, n = 499). TEAEs with perampanel 4 mg/d occurred in 419 of 1376 (30.5%) and 148 of 499 (29.7%) patients with focal and FBTC seizures, respectively; most common was dizziness. The proportion of TEAEs was similar with or without EIASMs.

SIGNIFICANCE

This post hoc analysis showed adjunctive perampanel 4 mg/d was efficacious and well tolerated in patients with focal seizures, with or without FBTC seizures. This dose may be a valuable treatment option in patients unable to tolerate higher perampanel doses up to 12 mg/d.

Safety and efficacy of adjunctive cenobamate (YKP3089) in patients with uncontrolled focal seizures: a multicentre, double-blind, randomised, placebo-controlled, dose-response trial

BACKGROUND

More than a third of patients with epilepsy are treatment resistant, and thus new, more effective therapies to achieve seizure freedom are needed. Cenobamate (YKP3089), an investigational antiepileptic drug, has shown broad-spectrum anticonvulsant activity in preclinical studies and seizure models. We aimed to evaluate the safety, efficacy, and tolerability of adjunctive cenobamate in patients with uncontrolled focal (partial)-onset epilepsy.

METHODS

We did a multicentre, double-blind, randomised, placebo-controlled, dose-response study at 107 epilepsy and neurology centres in 16 countries. Adult patients (aged 18-70 years) with focal seizures despite treatment with 1-3 antiepileptic drugs were randomly assigned (1:1:1:1) via an interactive web response system, by block sizes of 4 within each country, to adjuvant once daily oral cenobamate at dose groups of 100 mg, 200 mg, or 400 mg, or placebo following an 8-week baseline assessment. Patients, investigators, and study personnel were masked to treatment assignment. The study included a 6-week titration phase and 12-week maintenance phase. The primary efficacy outcomes were percentage change in 28-day focal seizure frequency (focal aware motor, focal impaired awareness, or focal to bilateral tonic-clonic seizures) from baseline analysed in the modified intention-to-treat population (≥1 dose and any post-baseline seizure data) and responder rates (≥50% reduction) analysed in the maintenance phase population (≥1 dose in the maintenance phase and any maintenance phase seizure data). The primary efficacy outcomes were analysed using a hierarchal step-down procedure comparing 200 mg versus placebo, 400 mg versus placebo, then 100 mg versus placebo. Safety and tolerability were compared descriptively across treatment groups for all randomised patients. This study is registered with ClinicalTrials.gov, number NCT01866111.

FINDINGS

Between July 31, 2013, and June 22, 2015, 437 patients were randomly assigned to either placebo (n=108) or cenobamate 100 mg (n=108), 200 mg (n=110), or 400 mg (n=111). Of these patients, 434 (106 [98%] in placebo group, 108 [100%] in 100 mg group, 109 [99%] in 200 mg group, and 111 [100%] in 400 mg group) were included in the modified intention-to-treat population, and 397 (102 [94%] in placebo group, 102 [94%] in 100 mg group, 98 [89%] in 200 mg group, and 95 [86%] in 400 mg group) were included in the modified intention-to-treat maintenance phase population. Median percentage changes in seizure frequency were -24·0% (IQR -45·0 to -7·0%) for the placebo group compared with -35·5% (-62·5 to -15·0%; p=0·0071) for the 100 mg dose group, -55·0% (-73·0 to -23·0%; p<0·0001) for the 200 mg dose group, and -55·0% (-85·0 to -28·0%; p<0·0001) for the 400 mg dose group. Responder rates during the maintenance phase were 25% (26 of 102 patients) for the placebo group compared with 40% (41 of 102; odds ratio 1·97, 95% CI 1·08-3·56; p=0·0365) for the 100 mg dose group, 56% (55 of 98; 3·74, 2·06-6·80; p<0·0001) for the 200 mg dose group, and 64% (61 of 95; 5·24, 2·84-9·67; p<0·0001) for the 400 mg dose group. Treatment-emergent adverse events occurred in 76 (70%) of 108 patients in the placebo group, 70 (65%) of 108 in the 100 mg group, 84 (76%) of 110 in the 200 mg group, and 100 (90%) of 111 in the 400 mg group. Treatment-emergent adverse events led to discontinuation in five (5%) patients in the placebo group, 11 (10%) in the 100 mg dose group, 15 (14%) in the 200 mg dose group, and 22 (20%) in the 400 mg dose group. One serious case of drug reaction with eosinophilia and systemic symptoms occurred in the 200 mg cenobamate group. No deaths were reported.

INTERPRETATION

Adjunctive cenobamate reduced focal (partial)-onset seizure frequency, in a dose-related fashion. Treatment-emergent adverse events were most frequent in the highest dose group. Cenobamate appears to be an effective treatment option in patients with uncontrolled focal seizures.

FUNDING

SK Life Science.

Levetiracetam and brivaracetam: a review of evidence from clinical trials and clinical experience

Until the early 1990s, a limited number of antiepileptic drugs (AEDs) were available. Since then, a large variety of new AEDs have been developed and introduced, several of them offering new modes of action. One of these new AED families is described and reviewed in this article. Levetiracetam (LEV) and brivaracetam (BRV) are pyrrolidone derivate compounds binding at the presynaptic SV2A receptor site and are thus representative of AEDs with a unique mode of action. LEV was extensively investigated in randomized controlled trials and has a very promising efficacy both in focal and generalized epilepsies. Its pharmacokinetic profile is favorable and LEV does not undergo clinically relevant interactions. Adverse reactions comprise mainly asthenia, somnolence, and behavioral symptoms. It has now been established as a first-line antiepileptic drug. BRV has been recently introduced as an adjunct antiepileptic drug in focal epilepsy with a similarly promising pharmacokinetic profile and possibly increased tolerability concerning psychiatric adverse events. This review summarizes the essential preclinical and clinical data of LEV and BRV that is currently available and includes the experiences at a large tertiary referral epilepsy center.

Ultra-Rare Genetic Variation in the Epilepsies: A Whole-Exome Sequencing Study of 17,606 Individuals

Sequencing-based studies have identified novel risk genes associated with severe epilepsies and revealed an excess of rare deleterious variation in less-severe forms of epilepsy. To identify the shared and distinct ultra-rare genetic risk factors for different types of epilepsies, we performed a whole-exome sequencing (WES) analysis of 9,170 epilepsy-affected individuals and 8,436 controls of European ancestry. We focused on three phenotypic groups: severe developmental and epileptic encephalopathies (DEEs), genetic generalized epilepsy (GGE), and non-acquired focal epilepsy (NAFE). We observed that compared to controls, individuals with any type of epilepsy carried an excess of ultra-rare, deleterious variants in constrained genes and in genes previously associated with epilepsy; we saw the strongest enrichment in individuals with DEEs and the least strong in individuals with NAFE. Moreover, we found that inhibitory GABA_A receptor genes were enriched for missense variants across all three classes of epilepsy, whereas no enrichment was seen in excitatory receptor genes. The larger gene groups for the GABAergic pathway or cation channels also showed a significant mutational burden in DEEs and GGE. Although no single gene surpassed exome-wide significance among individuals with GGE or NAFE, highly constrained genes and genes encoding ion channels were among the lead associations; such genes included CACNA1G, EEF1A2, and GABRG2 for GGE and LGI1, TRIM3, and GABRG2 for NAFE. Our study, the largest epilepsy WES study to date, confirms a convergence in the genetics of severe and less-severe epilepsies associated with ultra-rare coding variation, and it highlights a ubiquitous role for GABAergic inhibition in epilepsy etiology.

Is there a place for surgical treatment of nonpharmacoresistant epilepsy?

Epilepsy surgery has been shown to be the best possible treatment in well-defined and difficult-to-treat epilepsy syndromes, such as mesial temporal lobe epilepsy with unilateral hippocampal sclerosis, even early in the course of the disease if pharmacoresistance is proven. This review addresses the question if epilepsy surgery may be justified today even in nonpharmacoresistant cases. There are two possible groups of patients: first, there are epilepsy syndromes with a benign spontaneous course or with a potentially good treatment prognosis under appropriate antiepileptic drug (AED) treatment. Second, there are epilepsies with potentially worse AED treatment prognosis in which appropriate AED treatment has not yet been applied because of the short course of the disease, tolerability problems that prevented usually effective dosing, or adherence issues. In group one, the good spontaneous prognosis or the usually satisfying course under AED treatment in line with the commonly generalized underlying epileptogenesis does not suggest that epilepsy surgery is a realistic alternative, not even in cases with distinct focal clinical and/or electroencephalography (EEG) patterns like in Rolandic epilepsy with centrotemporal spikes. In the second group, the recent International League Against Epilepsy (ILAE) definition should allow assessment of individual pharmacoresistance early after the onset of the disease in order to avoid any delay. Concerns about a potential disease-specific or drug-specific cognitive decline that could be avoided in early surgery are speculative, a matter of controversial discussion, and certainly not relevant, if pharmacoresistance is consequently addressed in time according to the ILAE recommendations. One should also not forget that even in typically pharmacoresistant epilepsy syndromes that are suitable for surgical procedures, satisfying courses do exist that would not require early or any epilepsy surgery. Therefore, in almost any instance, epilepsy surgery as initial treatment or immediately after a first AED is still not recommended although, especially in cases with nonadherence to AEDs, it may be occasionally considered in order to outweigh the risks of ongoing seizures and epilepsy if surgery is not performed.

Efficacy, Retention, and Tolerability of Brivaracetam in Patients With Epileptic Encephalopathies: A Multicenter Cohort Study From Germany

Objective: To evaluate the efficacy and tolerability of brivaracetam (BRV) in a severely drug refractory cohort of patients with epileptic encephalopathies (EE).

Method: A multicenter, retrospective cohort study recruiting all patients treated with EE who began treatment with BRV in an enrolling epilepsy center between 2016 and 2017.

Results: Forty-four patients (27 male [61%], mean age 29 years, range 6 to 62) were treated with BRV. The retention rate was 65% at 3 months, 52% at 6 months and 41% at 12 months. A mean retention time of 5 months resulted in a cumulative exposure to BRV of 310 months. Three patients were seizure free during the baseline. At 3 months, 20 (45%, 20/44 as per intention-to-treat analysis considering all patients that started BRV including three who were seizure free during baseline) were either seizure free (n = 4; 9%, three of them already seizure-free at baseline) or reported at least 25% (n = 4; 9%) or 50% (n = 12; 27%) reduction in seizures. An increase in seizure frequency was reported in two (5%) patients, while there was no change in the seizure frequency of the other patients. A 50% long-term responder rate was apparent in 19 patients (43%), with two (5%) free from seizures for more than six months and in nine patients (20%, with one [2 %] free from seizures) for more than 12 months. Treatment-emergent adverse events were predominantly of psychobehavioural nature and were observed in 16%.

Significance: In this retrospective analysis the rate of patients with a 50% seizure reduction under BRV proofed to be similar to those seen in regulatory trials for focal epilepsies. BRV appears to be safe and relatively well tolerated in EE and might be considered in patients with psychobehavioral adverse events while on levetiracetam.

Use of brivaracetam in genetic generalized epilepsies and for acute, intravenous treatment of absence status epilepticus

OBJECTIVE

The objective of this study was to evaluate effectiveness, retention, and tolerability of brivaracetam (BRV) in genetic generalized epilepsies (GGE) in clinical practice.

METHODS

A multicenter, retrospective cohort study recruiting all patients that started BRV in 2016 and 2017.

RESULTS

A total of 61 patients (mean age = 29.8, range = 9-90 years, 41 female [67%]) were treated with BRV. They were difficult to control, with 2.4 failed antiepileptic drugs (AEDs) in the past, taking 1.9 AEDs on average at baseline. The length of exposure to BRV ranged from 7 days to 24 months, with a mean retention time of 7.9 months, resulting in a total exposure time to BRV of 483 months. The retention rate was 82% at 3 months and 69% at 6 months. Efficacy at 3 months was 36% (50% responder rate), with 25% seizure-free for 3 months. Patients with juvenile myoclonic epilepsy showed a responder rate of 60%, with 40% being free of any seizures. Long-term 50% responder rate was present in 17 patients (28%; 11 seizure-free [18%]) for >6 months and in 14 patients (23%; 10 seizure-free [16%]) for >12 months. Treatment-emergent adverse events were observed in 26% of the patients, with the most common being somnolence, ataxia, and psychobehavioral adverse events. Use of intravenous BRV with bolus injection of 200-300 mg in two females with absence status epilepticus was well tolerated, but did not result in cessation of status epilepticus.

SIGNIFICANCE

Use of BRV in GGE is well tolerated, and 50% responder rates are similar to those observed in the regulatory trials for focal epilepsies. An immediate switch from levetiracetam (LEV) to BRV at a ratio of 15:1 is feasible. The occurrence of psychobehavioral adverse events seems less prominent than under LEV, and a switch to BRV can be considered in patients with LEV-induced adverse events.

European trends in epilepsy surgery

OBJECTIVE

Resective surgery is effective in treating drug-resistant focal epilepsy, but it remains unclear whether improved diagnostics influence postsurgical outcomes. Here, we compared practice and outcomes over 2 periods 15 years apart.

METHODS

Sixteen European centers retrospectively identified 2 cohorts of children and adults who underwent epilepsy surgery in the period of 1997 to 1998 (n = 562) or 2012 to 2013 (n = 736). Data collected included patient (sex, age) and disease (duration, localization and diagnosis) characteristics, type of surgery, histopathology, Engel postsurgical outcome, and complications, as well as imaging and electrophysiologic tests performed for each case. Postsurgical outcome predictors were included in a multivariate logistic regression to assess the strength of date of surgery as an independent predictor.

RESULTS

Over time, the number of operated cases per center increased from a median of 31 to 50 per 2-year period (p = 0.02). Mean disease duration at surgery decreased by 5.2 years (p < 0.001). Overall seizure freedom (Engel class 1) increased from 66.7% to 70.9% (adjusted p = 0.04), despite an increase in complex surgeries (extratemporal and/or MRI negative). Surgeries performed during the later period were 1.34 times (adjusted odds ratio; 95% confidence interval 1.02-1.77) more likely to yield a favorable outcome (Engel class I) than earlier surgeries, and improvement was more marked in extratemporal and MRI-negative temporal epilepsy. The rate of persistent neurologic complications remained stable (4.6%-5.3%, p = 0.7).

CONCLUSION

Improvements in European epilepsy surgery over time are modest but significant, including higher surgical volume, shorter disease duration, and improved postsurgical seizure outcomes. Early referral for evaluation is required to continue on this encouraging trend.

Characteristics and healthcare situation of adult patients with tuberous sclerosis complex in German epilepsy centers

OBJECTIVE

The objective of the present study was to collect systematic data on the care of adult patients with tuberous sclerosis complex (TSC) in German epilepsy centers, to describe the characteristics of patients in this age group, and to clarify whether and how the recommended interdisciplinary care is implemented.

METHODS

This retrospective survey involved 12 major epilepsy centers in Germany. Aggregated data were collected based on an electronic questionnaire that addressed the sociodemographic data, characteristics of the epilepsy syndromes, and general healthcare setting of adult patients with TSC.

RESULTS

The survey included 262 patients (mean age: 36.2±9.0years) with TSC, most of whom were reported to live in either a home for persons with a disability (37.0%), a residential care home (6.9%), or with their parents (31.1%). A further 13.0% were self-sustaining, and 8.8% were living with a partner. Most patients presented with focal (49.6%) or multifocal (33.2%) epilepsy, with complex partial, dialeptic, and automotor seizures in 66% of patients and generalized tonic-clonic seizures in 63%. Drug-refractory epilepsy was seen in 78.2% of patients, and 17.6% were seizure-free at the time of the survey. Of the 262 patients, presurgical diagnostics were performed in 27% and epilepsy surgery in 9%, which rendered 50% of these patients seizure-free. Renal screening had been performed in 56.1% within the last three years and was scheduled to be performed in 58.0%. Cases of renal angiomyolipoma were present in 46.9% of the patients. Dermatologic and pulmonary screenings were known to be planned for only few patients.

CONCLUSION

Despite TSC being a multisystem disorder causing considerable impairment, every fifth adult patient is self-sustaining or living with a partner. In clinical practice, uncontrolled epilepsy and renal angiomyolipoma are of major importance in adult patients with TSC. Most patients suffer from focal or multifocal epilepsy, but epilepsy surgery is performed in less than 10% of these patients. Interdisciplinary TSC centers may help to optimize the management of patients with TSC regardless of age and ensure early and adequate treatment that also considers the advances in new therapeutic options.

Periodic EEG patterns in sporadic Creutzfeld-Jakob-Disease can be benzodiazepine-responsive and be difficult to distinguish from non-convulsive status epilepticus

PURPOSE

Periodic discharges in EEG and a history of rapidly progressive dementia are known to be associated with sporadic Creutzfeld-Jakob Disease (sCJD). Doubts regarding this rare but fatal diagnosis can arise, when episodic symptoms (seizures, psychiatric features, speech disturbances) are present and the EEG shows epileptiform discharges within this periodicity. This scenario may indicate non-convulsive status epilepticus (NCSE), which is - in contrast to sCJD - a treatable and frequent condition.

METHODS

Herein we report a small retrospective study of 4 elderly patients, who suffered from sCJD, but due to episodic symptoms and benzodiazepine-responsive epileptiform discharges in combination to a subacute cognitive decline, NCSE was considered as a potential differential diagnosis and therefore treated aggressively.

RESULTS

Ultimately, this treatment was not successful and sCJD was diagnosed in all cases. Hence, there was no diagnostic and prognostic value of abolishing periodic discharges in EEG via benzodiazepines in differentiating sCJD from NCSE in our series.

CONCLUSION

These findings indicate that periodic discharges in sCJD can be responsive to benzodiazepines andnot necessarily help to differentiate differentiation between sCJD and NCSE of other causes. We argue that an aggressive anticonvulsive treatment in this scenario should be considered cautiously, especially for invasive options like general anesthesia.