Long-term efficacy and safety of eslicarbazepine acetate monotherapy for adults with newly diagnosed focal epilepsy: An open-label extension study

Objective

To assess the efficacy, safety, and tolerability of eslicarbazepine acetate (ESL) monotherapy during long‐term treatment.

Methods

An open‐label extension (OLE) study was conducted in adults completing a phase 3, randomized, double‐blind, noninferiority trial, during which they had received monotherapy with either once‐daily ESL or twice‐daily controlled‐release carbamazepine (CBZ‐CR) for newly diagnosed focal epilepsy. In the OLE study, all patients received ESL (800‐1600 mg/d) for 2 years. Primary efficacy outcome was retention time (from baseline of the OLE study). Secondary efficacy assessments included seizure freedom rate (no seizures during the OLE study) and responder rate (≥50% seizure frequency reduction from baseline of double‐blind trial). Safety assessments included evaluation of treatment‐emergent adverse events (TEAEs).

Results

Of 206 randomized patients, 96 who received ESL in the double‐blind trial (ESL/ESL) and 88 who received CBZ‐CR in the double‐blind trial (CBZ‐CR/ESL) were treated with ESL monotherapy (89.3% overall). Treatment retention time was similar between groups, with low probability of ESL withdrawal overall (<0.07 at any time). After 24 months, the probability of ESL withdrawal was 0.0638 (95% confidence interval [CI] = 0.0292‐0.1366) in the ESL/ESL group and 0.0472 (95% CI = 0.0180‐0.1210) in the CBZ‐CR/ESL group. Seizure freedom rates were 90.6% (ESL/ESL) and 80.7% (CBZ‐CR/ESL; P = .0531). Responder rates remained >80% in both groups throughout the study. Incidence of serious TEAEs was similar between groups (7.3% vs 5.7%; 0% vs 1.1% possibly related), as were the incidences of TEAEs considered at least possibly related to treatment (17.7% vs 18.2%) and TEAEs leading to discontinuation (3.1% vs 4.5%). The types of TEAEs were generally consistent with the known safety profile of ESL.

Significance

ESL monotherapy was efficacious and generally well tolerated over the long term, including in patients who transitioned from CBZ‐CR monotherapy. No new safety concerns emerged.

Idiopathic Primary Hypoparathyroidism Presenting as Focal Seizures in a Neonate: A Rare Occurrence

Focal seizures in neonates presenting to the emergency department can be potentially dangerous and life-threatening. Hypoparathyroidism is an exceedingly rare but treatable cause of focal neonatal seizures. Due to its weak association with neonatal seizures, hypoparathyroidism often remains undetected as a potential cause. We hereby elucidate a rare case of idiopathic hypoparathyroidism presenting as right-sided focal seizures in a 12-day-old female neonate with an uneventful birth history. Despite the administration of antibiotics and phenobarbitone, the seizures remained unabated. Laboratory workup revealed the diagnosis of late-onset hypocalcemia with severe hypoparathyroidism. The patient was subsequently treated with calcium supplements and alfacalcidol. Thereafter, the frequency of seizures gradually decreased and the same treatment regimen was continued until the patient was seizure-free. The patient continues to do well to date with complete remission of his clinical symptoms.

Efficacy, safety, and tolerability of adjunctive perampanel in patients from China with focal seizures or generalized tonic-clonic seizures: Post hoc analysis of phase III double-blind and open-label extension studies

Aims

This post hoc analysis assessed the efficacy and safety/tolerability of adjunctive perampanel in patients from China (aged ≥12 years) with focal seizures (FS), with/without focal to bilateral tonic‐clonic seizures (FBTCS), or generalized tonic‐clonic seizures (GTCS).

Methods

Study centers in China were identified using data from five double‐blind, randomized, phase III studies of adjunctive perampanel (2‐12 mg/day) and their open‐label extensions (OLEx). Efficacy assessments included median percent reduction in seizure frequency per 28 days, and 50% and 75% responder and seizure‐freedom rates. Safety/tolerability assessments included monitoring of treatment‐emergent adverse events (TEAEs).

Results

Overall, 277 patients (placebo, n = 79; perampanel, n = 198) were included in the double‐blind safety analysis set. The full analysis set comprised 274 patients (FS, n = 238 [placebo, n = 60; perampanel, n = 178]; FBTCS, n = 120 [placebo, n = 31; perampanel, n = 89]; GTCS, n = 36 [placebo, n = 18; perampanel, n = 18]). Median percent reductions in seizure frequency for placebo vs perampanel were as follows: 16.6% vs 32.4% (FS; P < 0.05) and 39.1% vs 48.2% (FBTCS; not significant [NS]) at 4‐12 mg/day, and 37.9% vs 82.6% (GTCS; NS) at 8 mg/day; 50% responder rates were 31.7% vs 37.4% (FS; NS), 48.4% vs 51.9% (FBTCS; NS), and 33.3% vs 61.1% (GTCS; NS), respectively. Seizure‐freedom rates were 1.7% vs 9.2%, 16.1% vs 25.3%, and 16.7% vs 44.4%, respectively (all NS). Overall, 262 patients entered the OLEx (FS, n = 228; GTCS, n = 34). Perampanel was efficacious for up to four years for FS and FBTCS and up to two years for GTCS. Across the double‐blind and OLEx studies, TEAEs were reported in 65.7% and 81.3% of perampanel‐treated patients, respectively; the most common was dizziness. Efficacy and safety/tolerability outcomes were generally similar between Chinese and non‐Chinese patients.

Conclusion

Adjunctive perampanel (up to 12 mg/day) may be a suitable treatment for Chinese patients with FS, with/without FBTCS, or GTCS, with similar efficacy and safety/tolerability compared to non‐Chinese patients.

Brivaracetam substituting other antiepileptic treatments: Results of a retrospective study in German epilepsy centers

OBJECTIVE

To evaluate the success of initiation of adjunctive brivaracetam in patients who required a change in antiepileptic drug (AED) regimen and substituted at least one AED with brivaracetam.

METHODS

In this retrospective noninterventional study conducted in specialized epilepsy centers across Germany, patients initiated adjunctive brivaracetam between February 15, 2016, and August 31, 2016, as part of an intended change in AED regimen. The primary effectiveness variable was the proportion of patients who continued on brivaracetam after 3 months, and withdrew at least one AED either before or within 6 months after brivaracetam initiation.

RESULTS

Five hundred and six patients had at least one brivaracetam dose and were included in the safety set (SS). Four hundred and seventy patients started to reduce the dose of one AED before/after brivaracetam initiation, had at least one concomitant AED at brivaracetam initiation, and were included in the full analysis set (FAS) for effectiveness analyses. At baseline, patients had a median of seven lifetime AEDs and a median of 3.8 seizures/28 days. In the SS, 85.2% of patients withdrew one AED before/after initiation of brivaracetam, most commonly levetiracetam (49.4%). 46.2% of patients substituted another AED with brivaracetam within 24 hours (fast withdrawal). The proportions of patients (FAS) who continued on brivaracetam after 3 and 6 months and withdrew one AED were 75.5% and 46.6%, respectively. After 6 months, 32.1% of patients were 50% responders; 13.0% were seizure-free. In the SS, 34.6% of patients reported treatment-emergent adverse events (TEAEs); 21.9% had TEAEs that were assessed by the treating physician as drug-related. Incidences of behavioral AEs before (3-month baseline) and after brivaracetam initiation in patients who withdrew levetiracetam were 19.2% and 8.0%, respectively (5.0% and 7.7% in patients who withdrew other AEDs).

SIGNIFICANCE

Brivaracetam was effective and well-tolerated in patients who required a change in AED drug regimen and initiated adjunctive brivaracetam in German clinical practice.

The Humanistic and Economic Burden of Pediatric Focal Seizures in the United States

OBJECTIVE

To better understand the humanistic and economic burden of focal seizures in children 2-12 years old.

METHODS

We conducted a targeted literature review by searching MEDLINE for English-language publications reporting on children 2-12 years old with focal seizures published in the United States since 2008.

RESULTS

Thirty-five publications were included. Incidence of focal seizures was 23.2 to 47.1 per 100,000 children per year; prevalence was 2.0 per 1,000 children, and ranged from 1.6 - 2.6 per 1,000 in patients of any age. Life expectancy was 47.3-61.8 years among children 3-12 years old. Patients took several antiepileptic drugs and experienced frequent seizures, sleep disorders, mood disorders, migraine, and seizure-related injuries (eg, bone fractures, sprains, open wounds). Children with focal seizures scored below average on cognitive assessments and up to 42%, 16%, and 19% had depression, anxiety, and attention-deficit disorder, respectively. Patients of any age had about 10 outpatient visits (2 epilepsy-related), 2 inpatient visits (less than 1 epilepsy-related), and 24 procedures (1 epilepsy-related) per year. Medication adherence was low: only half of pediatric patients maintained ≥90% adherence over 6 months. Annual total health care costs among patients of any age ranged from $18,369 - 38,549; first-year total health care costs for children were $19,883.

CONCLUSIONS

Incidence and prevalence of focal seizures is high and the humanistic and economic burdens are significant. Future studies focused exclusively on children with focal seizures are needed to more precisely describe the burden. We also suggest further research and implementation of methods to improve medication adherence as an approach to lessen burden on these young patients.

Analysis of cutaneous allergic reactions in clinical trials of eslicarbazepine acetate

OBJECTIVES

To evaluate cutaneous allergic reactions in clinical trials of adjunctive eslicarbazepine acetate (ESL) for focal seizures.

MATERIALS AND METHODS

Data were analyzed from three phase III randomized, double-blind, placebo-controlled studies of adjunctive ESL in adults (placebo, n = 426; ESL, n = 1021) and two randomized, double-blind, placebo-controlled studies (and open-label extensions [OLEs]) of adjunctive ESL in children aged 4-17 years (placebo, n = 160; ESL, n = 202; OLE, n = 337).

RESULTS

Adult studies: Rash (ESL 1.9%, placebo 0.9%) and pruritus (ESL 1.2%, placebo 0.9%) were the most frequent rash-related treatment-emergent adverse events (TEAEs). Most rash-related TEAEs were mild or moderate in severity. Incidence of rash increased with increasing ESL dose, but was not higher for patients who initiated treatment with higher ESL doses. Pediatric studies: Allergic dermatitis (ESL 3.0%, placebo 0) and rash (controlled studies: ESL 1.0%, placebo 1.3%; OLE periods: ESL ≤1.2%) were the most frequent rash-related TEAEs. There was one case of DRESS in the ESL group. Most rash-related TEAEs were mild or moderate in severity and judged as not related to treatment with ESL.

CONCLUSIONS

Serious skin rashes were rare during adult and pediatric clinical trials of ESL. Although the incidence of rash with ESL was low, it is important for patients/caregivers to be made aware of the potential signs and symptoms associated with serious skin rashes.

Efficacy, safety, and tolerability of perampanel in Asian and non-Asian patients with epilepsy

People of different ethnic or racial backgrounds may experience variations in pharmacokinetic and pharmacodynamic responses to drug therapies. Our post hoc analysis evaluated the efficacy, safety, and tolerability of perampanel in Asian and non-Asian populations with refractory focal seizures with or without focal to bilateral tonic-clonic (FBTC) seizures. This analysis pooled data from 4 randomized, placebo-controlled, phase-3 studies involving patients aged ≥12 years who have focal seizures with or without FBTC seizures. Patients were receiving 2, 4, 8, or 12 mg perampanel (or placebo) by the end of a 6-week titration period and for a further 13 weeks during the maintenance phase. Efficacy endpoints included median percent change in seizure frequency per 28 days, and 50% and seizure-freedom responder rates relative to baseline. The median percent change in seizure frequency per 28 days from baseline was significantly greater than placebo for perampanel 8 and 12 mg (-31.1% and -38.1% change, respectively; each P < 0.0001) in the Asian population, and for perampanel 4, 8, and 12 mg (-21.1% [P = 0.0001], -26.3% [P < 0.0001], and -27.7% [P = 0.0001] change, respectively) in the non-Asian population. The 50% responder rate relative to baseline was significantly greater than placebo for perampanel 8 and 12 mg (40.1% and 43.8%, respectively; each P < 0.0001) in the Asian population, and for perampanel 4, 8, and 12 mg (29.4% [P = 0.0002], 32.8% [P < 0.0001] and 34.5% [P = 0.0001]), respectively, in the non-Asian population. Seizure-freedom rate among all patients was 4.9%-11.7% for perampanel 2, 4, 8, and 12 mg. The most frequently reported treatment-emergent adverse events (TEAEs) across both populations were dizziness, somnolence, irritability, headache, and fatigue. The most common psychiatric TEAEs were aggression and irritability. Perampanel demonstrated a favorable and similar risk-benefit profile in both Asian and non-Asian populations with refractory focal seizures.

Efficacy and safety of perampanel in generalized and focal to bilateral tonic-clonic seizures: A comparative study of Asian and non-Asian populations

Perampanel is an approved adjunctive treatment for focal seizures with or without focal to bilateral tonic-clonic (FBTC) seizures and generalized tonic-clonic (GTC) seizures. We compared efficacy and safety of perampanel vs placebo in Asian and non-Asian populations in a post hoc analysis of pooled data from 5 randomized phase 3 studies. Patients (≥12 years old) with focal + FBTC seizures received perampanel 2, 4, 8, or 12 mg or placebo; patients with GTC seizures received perampanel 8 mg or placebo (titration: 4-6 weeks; maintenance: 13 weeks). Efficacy endpoints included median percentage change in FBTC or GTC seizure frequency per 28 days and 50% responder rate relative to baseline. Median percentage change in FBTC seizure frequency was significantly greater for perampanel 8 and 12 mg than placebo in the Asian population (median difference from placebo: -30.32%, P = 0.0017; -30.06%, P = 0.0008, respectively) and perampanel 4, 8, and 12 mg in the non-Asian population (-35.07%, P = 0.0001; -37.78%, P < 0.0001; -34.53%, P < 0.0001, respectively). In both populations, median percentage change in GTC seizure frequency was significantly greater for perampanel 8 mg than placebo (median difference from placebo: Asian, -37.37%, P = 0.0139; non-Asian, -27.04%, P = 0.0006). The 50% responder rates were significantly greater than placebo for perampanel 8 and 12 mg for FBTC seizures (Asian: 58.0%, P = 0.0017 and 58.6%, P = 0.0013, respectively; non-Asian: 59.3%, P < 0.0001 and 54.3%, P = 0.0050, respectively) and perampanel 8 mg for GTC seizures (Asian: 57.6%, P = 0.0209; non-Asian: 68.8%, P = 0.0329). Pooled FBTC/GTC seizure data showed generally similar patterns of response to perampanel in both populations. The most frequent treatment-related adverse events were fatigue, irritability, dizziness, somnolence, and headache. Perampanel was effective, well tolerated, and can be considered a therapeutic option for FBTC/GTC seizures in Asian populations.

Quantified EEG for the Characterization of Epileptic Seizures versus Periodic Activity in Critically Ill Patients

Epileptic seizures (ES) are frequent in critically ill patients and their detection and treatment are mandatory. However, sometimes it is quite difficult to discriminate between ES and non-epileptic bursts of periodic activity (BPA). Our aim was to characterize ES and BPA by means of quantified electroencephalography (qEEG). Records containing either ES or BPA were visually identified and divided into 1 s windows that were 10% overlapped. Differential channels were grouped by frontal, parieto-occipital and temporal lobes. For every channel and window, the power spectrum was calculated and the area for delta (0–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), and beta (13–30 Hz) bands and spectral entropy (Se) were computed. Mean values of percentage changes normalized to previous basal activity and standardized mean difference (SMD) for every lobe were computed. We have observed that BPA are characterized by a selective increment of delta activity and decrease in Se along the scalp. Focal seizures (FS) always propagated and were similar to generalized seizures (GS). In both cases, although delta and theta bands increased, the faster bands (alpha and beta) showed the highest increments (more than 4 times) without modifications in Se. We have defined the numerical features of ES and BPA, which can facilitate its clinical identification.

Cortico-striatal synchronization in human focal seizures

Although a number of experimental and clinical studies have pointed out participation or an even more prominent role of basal ganglia in focal seizures, the mode of interaction between cortical and striatal signals remains unclear. In the present study, we took stereoelectroencephalographic (SEEG) recordings in drug-resistant epilepsy patients, to qualitatively and quantitatively analyse the ictal striatum activity as well as its synchronization with cerebral cortex. Eleven patients who underwent SEEG evaluation were prospectively included if they fulfilled two inclusion criteria: (i) at least one orthogonal intracerebral electrode contact explored the basal ganglia, in either their putaminal or caudate part; and (ii) at least two SEEG seizures were recorded. Cortical and subcortical regions of interest were defined and different periods of interest were analysed. SEEG was visually inspected and h2 non-linear correlation analysis performed to study functional connectivity between cortical region of interest and striatum. Six correlation indices were calculated. Two main patterns of striatal activation were recorded: the most frequent was characterized by an early alpha/beta activity that started within the first 5 s after seizure onset, sometimes concomitant with it. The second one was characterized by late, slower, theta/delta activity. A significant difference in h2 correlation indices was observed during the preictal and seizure onset period compared to background for global striatal index, mesio-temporal/striatal index, latero-temporal/striatal index, insular/striatal index, prefrontal/striatal index. In addition, a significant difference in h2 correlation indices was observed during the seizure termination period compared to all the other periods of interest for the six indices calculated. These results indicate that cortico-striatal synchronization can arise from the start of focal seizures. Depending on the ictal frequency pattern, desynchronization can occur later, but a late and terminal hypersynchronization progressively takes over. These changes in synchronization level between cortical and striatal activity might be part of an endogenous mechanism controlling the duration of abnormal oscillations within the striato-thalamo-cortical loop and thereby their termination. Pathophysiology of basal ganglia in focal seizures appears to be much more interlinked with the cortex than expected. Beyond the stereotypical features they could imprint to seizure semiology, their role in strengthening mechanisms underlying cessation of ictal propagation should inspire new rationales for deep brain stimulation in patients with intractable focal epilepsies.

The Role of Excitability and Network Structure in the Emergence of Focal and Generalized Seizures

Epileptic seizures are generally classified as either focal or generalized. It had been traditionally assumed that focal seizures imply localized brain abnormalities, whereas generalized seizures involve widespread brain pathologies. However, recent evidence suggests that large-scale brain networks are involved in the generation of focal seizures, and generalized seizures can originate in localized brain regions. Herein we study how network structure and tissue heterogeneities underpin the emergence of focal and widespread seizure dynamics. Mathematical modeling of seizure emergence in brain networks enables the clarification of the characteristics responsible for focal and generalized seizures. We consider neural mass network dynamics of seizure generation in exemplar synthetic networks and we measure the variance in ictogenicity across the network. Ictogenicity is defined as the involvement of network nodes in seizure activity, and its variance is used to quantify whether seizure patterns are focal or widespread across the network. We address both the influence of network structure and different excitability distributions across the network on the ictogenic variance. We find that this variance depends on both network structure and excitability distribution. High variance, i.e., localized seizure activity, is observed in networks highly heterogeneous with regard to the distribution of connections or excitabilities. However, networks that are both heterogeneous in their structure and excitability can underlie the emergence of generalized seizures, depending on the interplay between structure and excitability. Thus, our results imply that the emergence of focal and generalized seizures is underpinned by an interplay between network structure and excitability distribution.

First add-on perampanel for focal-onset seizures: An open-label, prospective study

Objectives

This study aimed to determine the efficacy and safety of perampanel added to monotherapy in patients with focal‐onset seizures, with or without secondarily generalized tonic‐clonic seizures.

Materials & Methods

In this multicentre, open‐label trial, enrolled patients were treated with perampanel monotherapy. During a 12‐week titration period, perampanel was incrementally increased by 2 mg/d over ≥2‐week intervals. Patients then entered a 24‐week maintenance period. The primary objective was to investigate the 50% responder rate in total seizure frequency, with 75% and 100% responder rates as secondary objectives. Treatment‐emergent adverse events (TEAEs) and adverse drug reactions were recorded. A post hoc analysis was performed to investigate the effect of titration speed and different concomitant AEDs on the efficacy and safety of perampanel.

Results

Of the 85 patients analysed, seizure reductions of 50%, 75% and 100% were observed in 80.0% (95% confidence interval [CI]: 69.9‐87.9), 71.8% (95% CI: 61.0‐81.0) and 47.1% (95% CI: 36.1‐58.2) during the maintenance period, respectively. The 50%, 75% and 100% response rates in patients with secondarily generalized tonic‐clonic seizures were 87.5% (95% CI: 61.7‐98.5), 87.5% (95% CI: 61.7‐98.5) and 75.0% (95% CI: 47.6‐92.7), respectively. The most common TEAEs were dizziness (50.0%), somnolence (9.8%) and headache (8.8%). The efficacy outcomes and safety profile of perampanel were more favourable with slow titration and relatively consistent when stratified by concomitant AEDs.

Conclusions

Perampanel was effective and well tolerated as a first add‐on to monotherapy in patients with focal‐onset seizures, with or without secondarily generalized seizures.

Subtraction Ictal SPECT coregistered to MRI (SISCOM) as a guide in localizing childhood epilepsy

Objective

To assess feasibility and efficacy of subtraction ictal SPECT coregistered to MRI (SISCOM) for epilepsy localization in children who are candidates for resective surgery.

Methods

We retrospectively reviewed all patients ≤16 years with drug‐resistant epilepsy screened for epilepsy surgery in the University Hospital of Leuven from January 2009 to January 2018. Fifty‐eight hospitalizations for ictal SPECT and 51 SISCOM analyses in 44 patients were included. Mean age was 9.1 years. Hospitalizations for SISCOM were analyzed in terms of multiple variables affecting feasibility and efficacy. The localization of SISCOM was compared with the localization of the presumed epileptogenic zone (PEZ) as determined by video‐EEG.

Results

SISCOM was feasible in terms of chronic medication management, rescue antiepileptic therapy during hospitalization, and operative timings. Radiotracer injection occurred within 30 seconds from seizure onset in 91.4% of the patients. ictal SPECT imaging was performed within two hours from injection in 100% of the patients (mean: 40 minutes). SISCOM was able to localize the PEZ in 51.0% (26/51) and to additionally lateralize the PEZ in 17.6% (9/51), achieving better localizations than ictal SPECT, FDG‐PET, and MRI (P < .01). SISCOM was useful to localize the PEZ in 25% of patients with poorly localizing video‐EEG and in 27.8% of MRI‐negative cases. The occurrence of habitual seizures during injection for ictal SPECT and the temporal localization of the PEZ both correlated with a better SISCOM localization (P < .05). 36.4% (16/44) patients were finally selected for resective surgery, with a 87.5% seizure‐free rate at 12 months. A localizing SISCOM was associated with seizure freedom in 66.7% and with a Engel I‐II in 75.0% of our patients.

Significance

SISCOM is a reliable tool to localize the epileptogenic zone in clinical practice and is both feasible and useful in children, adding precious presurgical information especially in patients with noninformative MRI or a poorly localizing video‐EEG.

Clinical outcomes of eslicarbazepine acetate monotherapy for focal-onset seizures: A multicenter audit

OBJECTIVE

To assess the effectiveness and tolerability of eslicarbazepine acetate (ESL) monotherapy in routine clinical practice for the treatment of focal-onset seizures.

METHODS

Multicenter, retrospective, observational study conducted in patients older than 16 years treated with ESL as first-line monotherapy or converted to ESL monotherapy from polytherapy or other monotherapy. Outcomes included 1-year retention rate, seizure-free rates after 6 and 12 months of monotherapy treatment, and safety/tolerability issues.

RESULTS

A total of 256 patients were included (106 first-line and 150 conversion to monotherapy; 56 patients aged >65 years). Overall, the 1-year retention rate was 79% (72.7% in the ≥65 years subgroup) and seizure-free rates at 6 and 12 months were 59.3% and 55.3% (72.2% and 67.3% in the ≥65 years subgroup), without significant differences when comparing first-line vs conversion-to-ESL monotherapy groups (P = .979). However, the conversion group was heterogeneous and included 43 (29.1%) patients that were seizure free the year prior ESL introduction. A substantially higher proportion of patients remained seizure free for the entire follow-up among those who initiated ESL due to tolerability problems compared with those treated due to inadequate seizure control (71.4% vs 37.3%). Overall, 62 of 256 (24.2%) patients reported AEs (39.3% in >65 years subgroup) and led to discontinuation in 20/256 (7.8%) patients (12.5% in >65 years subgroup). Commonly reported AEs were somnolence (6.6%), dizziness (6.3%), and headache (4.3%). Hyponatremia was recorded in five patients, the majority (4/5) of whom were older than 65 years.

CONCLUSIONS

Eslicarbazepine acetate was effective and well-tolerated as first-line or conversion to monotherapy in a clinical setting in adult and elderly patients with focal-onset seizures.

Seizure detection based on heart rate variability using a wearable electrocardiography device

OBJECTIVE

To assess the feasibility and accuracy of seizure detection based on heart rate variability (HRV) using a wearable electrocardiography (ECG) device. Noninvasive devices for detection of convulsive seizures (generalized tonic-clonic and focal to bilateral tonic-clonic seizures) have been validated in phase 2 and 3 studies. However, detection of nonconvulsive seizures still needs further research, since currently available methods have either low sensitivity or an extremely high false alarm rate (FAR).

METHODS

In this phase 2 study, we prospectively recruited patients admitted to long-term video-EEG monitoring (LTM). ECG was recorded using a dedicated wearable device. Seizures were automatically detected using HRV parameters computed off-line, blinded to all other data. We compared the performance of 26 automated algorithms with the seizure time-points marked by experts who reviewed the LTM recording. Patients were classified as responders if >66% of their seizures were detected.

RESULTS

We recruited 100 consecutive patients and analyzed 126 seizures (108 nonconvulsive and 18 convulsive) from 43 patients who had seizures during monitoring. The best-performing HRV algorithm combined a measure of sympathetic activity with a measure of how quickly HR changes occurred. The algorithm identified 53.5% of the patients with seizures as responders. Among responders, detection sensitivity was 93.1% (95% CI: 86.6%-99.6%) for all seizures and 90.5% (95% CI: 77.4%-97.3%) for nonconvulsive seizures. FAR was 1.0/24 h (0.11/night). Median seizure detection latency was 30 s. Typically, patients with prominent autonomic nervous system changes were responders: An ictal change of >50 heartbeats per minute predicted who would be responder with a positive predictive value of 87% and a negative predictive value of 90%.

SIGNIFICANCE

The automated HRV algorithm, using ECG recorded with a wearable device, has high sensitivity for detecting seizures, including the nonconvulsive ones. FAR was low during the night. This approach is feasible in patients with prominent ictal autonomic changes.

Detection of focal electroencephalogram signals using higher-order moments in EMD-TKEO domain

Detection of epileptogenic focus based on electroencephalogram (EEG) signal screening is an important pre-surgical step to remove affected regions inside the human brain. Considering the fact above, in this work, a novel technique for detection of focal EEG signals is proposed using a combination of empirical mode decomposition (EMD) and Teager–Kaiser energy operator (TKEO). EEG signals belonging to focal (Fo) and non-focal (NFo) groups were at first decomposed into a set of intrinsic mode functions (IMFs) using EMD. Next, TKEO was applied on each IMF and two higher-order statistical moments namely skewness and kurtosis were extracted as features from TKEO of each IMF. The statistical significance of the selected features was evaluated using student's t-test and based on the statistical test, features from first three IMFs which show very high discriminative capability were selected as inputs to a support vector machine classifier for discrimination of Fo and NFo signals. It was observed that the classification accuracy of 92.65% is obtained in classifying EEG signals using a radial basis kernel function, which demonstrates the efficacy of proposed EMD-TKEO based feature extraction method for computer-based treatment of patients suffering from focal seizures.

Serum sodium levels and related treatment-emergent adverse events during eslicarbazepine acetate use in adults with epilepsy

Objective

To examine the frequency of hyponatremia and potentially related symptoms in clinical trials of eslicarbazepine acetate (ESL) in adults with focal‐ (partial‐) onset seizures.

Methods

This post hoc, exploratory analysis included data from three controlled phase 3 trials of adjunctive ESL (400‐1200 mg once daily), two phase 3 trials of ESL monotherapy (1200‐1600 mg once daily), and their open‐label extension studies. Exploratory endpoints included clinical laboratory measurements of serum sodium concentrations ([Na⁺]), incidences of hyponatremia‐related treatment‐emergent adverse events (TEAEs), and incidences of TEAEs that are potential symptoms of hyponatremia.

Results

The controlled trials of adjunctive ESL and ESL monotherapy included 1447 (placebo, n = 426; ESL, n = 1021) and 365 (ESL, n = 365) patients, respectively; 639 and 274 patients continued onto uncontrolled, open‐label extensions. In the controlled and uncontrolled trials ≤3.3% of patients taking ESL had a minimum postdose [Na⁺] measurement ≤125 mEq/L, <9% had a >10 mEq/L decrease in [Na⁺] from baseline, <6% had a hyponatremia‐related TEAE, and <2% discontinued the controlled trials due to a hyponatremia‐related TEAE. Hyponatremia appeared to be more frequent in the monotherapy (vs adjunctive therapy) trials; in the controlled trials of adjunctive ESL and ESL monotherapy, incidence generally increased with increasing ESL dose. The majority of patients with an investigator‐reported TEAE of “hyponatremia” or “blood sodium decreased” did not have a corresponding laboratory [Na⁺] measurement ≤125 mEq/L. Some symptoms potentially related to hyponatremia (including nausea and vomiting) were more frequent in patients with a minimum postdose [Na⁺] measurement ≤125 mEq/L.

Significance

Reductions in serum sodium concentrations and hyponatremia‐related TEAEs occurred in a small number of patients taking ESL. Suspected hyponatremia should be confirmed and monitored via [Na⁺] measurements.

Brivaracetam efficacy and safety in focal epilepsy

Introduction: Brivaracetam (BRV) is an analog of levetiracetam (LEV) with 15-30 times greater affinity to SV2A and greater brain permeability than LEV. These properties have stimulated interest in its clinical trial data and post-marketing experience. Areas covered: The authors provide a background on epilepsy and its treatment, discuss the racetam family of antiepileptic drugs to which BRV belongs, and then discuss BRV properties and its efficacy and tolerability in the treatment of epilepsy. Expert opinion: While preclinical data suggest a broad spectrum of efficacy, BRV is only approved for focal epilepsy. The recommended starting dose is 100 mg per day, but in the absence of urgency, it may be prudent to start at 50 mg per day, considered the lowest effective dose. There was no added benefit when BRV was used adjunctively with LEV in clinical trials. However, post-marketing data suggest that some patients may experience improved seizure control when switching from LEV. Behavioral adverse effects seemed less common than with LEV, and most patients switched to BRV after experiencing behavioral adverse effects on LEV reported improvement. Prior or anticipated intolerability to LEV is the strongest indication for BRV in clinical practice.

Intermittent perilesional edema and contrast enhancement in epilepsy with calcified neurocysticercosis may help to identify the seizure focus

Neurocysticercosis is a frequent cause of seizures in endemic countries. It is caused by the larvae of the tapeworm Taenia solium. The larvae once hosted in the cerebral parenchyma evolve into viable cysts, called the vesicular stage (with little or no inflammatory reaction), and may remain at this stage for years, or may enter in an inflammatory-degenerative process (colloidal phase) that ends with calcified nodules. Edema and MRI contrast enhancement associated with these calcifications have been described, suggesting that it may be associated with seizures. However, most of these reports were either cross-sectional case-control series or case reports with a single time point MRI. Therefore, the clinical significance of recurring perilesional edema and contrast enhancement around calcified lesions is still uncertain. Here, we describe repeated MRIs of a patient with calcified neurocysticercosis over 4 years. The seizures were associated with edema and contrast enhancement that disappeared in the seizure-free periods, occurring only around one calcified nodule that coincided with the EEG findings and seizure semiology, although he had three additional calcifications. These findings support the association between pericalcification contrast enhancement and edema with recent seizures. This MRI finding may be a marker to define the epileptogenic focus in epilepsies with calcified neurocysticercosis.

Epileptiform activity contralateral to unilateral hippocampal sclerosis does not cause the expression of brain damage markers

OBJECTIVE

Patients with epilepsy often ask if recurrent seizures harm their brain and aggravate their epileptic condition. This crucial question has not been specifically addressed by dedicated experiments. We analyze here if intense bilateral seizure activity induced by local injection of kainic acid (KA) in the right hippocampus produces brain damage in the left hippocampus.

METHODS

Adult guinea pigs were bilaterally implanted with hippocampal electrodes for continuous video-electroencephalography (EEG) monitoring. Unilateral injection of 1 μg KA in the dorsal CA1 area induced nonconvulsive status epilepticus (ncSE) characterized by bilateral hippocampal seizure discharges. This treatment resulted in selective unilateral sclerosis of the KA-injected hippocampus. Three days after KA injection, the animals were killed, and the brains were submitted to ex vivo magnetic resonance imaging (MRI) and were processed for immunohistochemical analysis.

RESULTS

During ncSE, epileptiform activity was recorded for 27.6 ± 19.1 hours in both the KA-injected and contralateral hippocampi. Enhanced T1-weighted MR signal due to gadolinium deposition, mean diffusivity reduction, neuronal loss, gliosis, and blood-brain barrier permeability changes was observed exclusively in the KA-injected hippocampus. Despite the presence of a clear unilateral hippocampal sclerosis at the site of KA injection, no structural alterations were detected by MR and immunostaining analysis performed in the hippocampus contralateral to KA injection 3 days and 2 months after ncSE induction. Fluoro-Jade and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining at the same time points confirmed the absence of degenerating cells in the hippocampi contralateral to KA injection.

SIGNIFICANCE

We demonstrate that intense epileptiform activity during ncSE does not cause obvious brain damage in the hippocampus contralateral to unilateral hippocampal KA injection. These findings argue against the hypothesis that epileptiform activity per se contributes to focal brain injury in previously undamaged cortical regions.

[New antiepileptic drugs]

Antiepileptic drugs are the first treatment option in patients with epilepsy. Drugs developed after 2000 are known as third generation antiepileptic drugs. These medications offer new mechanisms of action and favorable pharmacokinetics, decreasing the occurrence of side effects and drug-drug interactions. Broad spectrum antiepileptic drugs, such as brivaracetam and clobazam are good choices for generalized tonic colonic seizures and are well tolerated.New sodium channel blockers such as lacosamide and eslicarbazepine, have a more "benign" side effect profile than the first or second generation of sodium channel blockers. These new drugs are useful therapies in patients with epilepsy of difficult control. Cannabidiol and fenfluramine are useful in the treatment of Dravet or Lennox Gastaut syndrome. Allopregnenolona and ganaxolone showed good efficacy in status epilepticus and could play an important future role in this clinical scenario.

Lacosamide monotherapy in clinical practice: A retrospective chart review

OBJECTIVE

To assess effectiveness and tolerability of first-line and conversion to lacosamide monotherapy for focal seizures.

MATERIALS AND METHODS

Retrospective, non-interventional chart review of lacosamide monotherapy patients aged ≥16 years in Europe. Outcomes included retention rate at observational point (OP) 3 (12 ± 3 months), seizure freedom rates at OP2 (6 ± 3 months) and OP3 and adverse drug reactions (ADRs).

RESULTS

A total of 439 patients were included (98 first-line and 341 conversion to monotherapy; 128 aged ≥65 years [25 first-line and 103 conversion to monotherapy]). First-line and conversion to monotherapy retention rates were 60.2% (59/98; 95% confidence interval [CI] 49.8%-70.0%) and 62.5% (213/341; 57.1%-67.6%), respectively. Kaplan-Meier estimates of 12-month retention rates were 81.2% and 91.4% for first-line and conversion to monotherapy, respectively. First-line and conversion to monotherapy retention rates in patients aged ≥65 years were 60.0% (38.7%-78.9%) and 68.9% (59.1%-77.7%), respectively. At OP2, 66.3% of first-line and 63.0% of conversion to monotherapy patients were seizure free. At OP3, 60.2% of first-line and 52.5% of conversion to monotherapy patients were seizure free. In the ≥65 years subgroup, seizure freedom rates at OP2 were 72.0% and 68.0% for first-line and converted to monotherapy, respectively, and at OP3, 68.0% and 56.3%, respectively. Overall, 52 of 439 (11.8%) patients reported ADRs (16.4% in ≥65 years subgroup), most commonly dizziness (5.0%), headache (2.1%) and somnolence (1.6%).

CONCLUSIONS

Lacosamide was effective and well tolerated as first-line or conversion to monotherapy in a clinical setting in adult and elderly patients with focal seizures.

Perampanel, an AMPA receptor antagonist: From clinical research to practice in clinical settings

Epileptic seizures are refractory to treatment in approximately one-third of patients despite the recent introduction of many newer antiepileptic drugs (AEDs). Development of novel AEDs therefore remains a high priority. Perampanel is a first-in-class non-competitive selective AMPA receptor antagonist with a unique mechanism of action. Clinical efficacy and safety of perampanel as adjunctive treatment for focal seizures with/without secondary generalization (±SG) and primary generalized tonic-clonic (PGTC) seizures have been established in five phase 3 randomized controlled trials (RCTs), and a long-term extension study, and perampanel is approved as monotherapy for focal seizures ±SG in the USA. In patients with focal seizures ±SG, add-on perampanel resulted in median percent reduction in seizure frequency 23.3%-34.5% and ≥50% responder rate 28.5%-37.6%; in PGTC seizures, these results were 76.5% and 64.2%, respectively. Efficacy among adolescents (reduction in seizure frequency 34.8%-35.6%; ≥50% responder rate 40.9%-45.0%) and elderly people (reduction in seizure frequency 12.5%-16.9%; ≥50% responder rate 22.2%-42.9%) is similar to those in adults, and results remain comparable between Asian (reduction in seizure frequency 17.3%-38.0%) and global populations. Perampanel has been extensively studied in real-world clinical practice, with similar efficacy and safety results to the RCTs (≥50% responder rate 12.8%-75.0%; adverse events of somnolence/sedation, dizziness, ataxia, and behavioral changes). Real-world observational studies suggest that perampanel tolerability can be improved by slow titration (2 mg every 2-4 weeks), and bedtime administration can mitigate somnolence and dizziness. Counseling about the potential for behavioral changes and close monitoring are recommended.

Eslicarbazepine acetate in the treatment of adults with partial-onset epilepsy: an evidence-based review of efficacy, safety and place in therapy

INTRODUCTION

Up to 30% of the patients diagnosed with epilepsy will continue suffering from seizures despite treatment with antiepileptic drugs, either in monotherapy or polytherapy. Hence, there remains the need to develop new effective and well-tolerated therapies.

AIM

The objective of this article was to review the evidence for the efficacy and safety of eslicarbazepine acetate (ESL) as adjunctive treatment in adult patients with focal onset seizures.

EVIDENCE REVIEW

ESL is the newest, third-generation, single enantiomer member of the dibenzazepine family. Following oral administration, ESL is rapidly and extensively metabolized by hepatic first-pass hydrolysis to the active metabolite eslicarbazepine, which has linear, dose-proportional pharmacokinetics and low potential for drug-drug interactions. Eslicarbazepine works as a competitive blocker of the voltage gated sodium channels; unlike carbamazepine (CBZ) and oxcarbazepine (OXC), it has a lower affinity for the resting state of the channels, and reduces their availability by selectively enhancing slow inactivation. Efficacy and safety of ESL have been assessed in four randomized, Phase III clinical trials: the median relative reduction in standardized seizure frequency was 33.4% and 37.8% in the ESL 800 and 1,200 mg daily dose groups, and the responder rates were 33.8% and 43.1%, respectively. The incidence of treatment-emergent adverse events (TEAEs) increased with raising the dosage (ESL 400 mg: 63.8%, ESL 800 mg: 67.0%, ESL 1,200 mg: 73.1%). The TEAEs were generally mild to moderate in intensity, and the most common were dizziness, somnolence, headache and nausea. Open-label studies confirmed the findings from the pivotal trials and demonstrated sustained therapeutic effect of ESL over time and improvement of tolerability profile in patients switching from OXC/CBZ. No unexpected safety signals emerged over >5 years of follow-up.

CONCLUSION

Once-daily adjunctive ESL at the doses of 800 and 1,200 mg was effective to reduce the seizure frequency and was fairly well tolerated in adults with focal onset epilepsy. Starting treatment at 400 mg/day, followed by 400 mg increments every 7-14 days, could provide the optimal balance of efficacy and tolerability.

Association between BACE1 gene polymorphisms and focal seizures in a Chinese Han population

BACKGROUND

Beta-secretase 1 (BACE1) is attracting increasing attention for its vital role in pathogenesis of many neuropsychiatric disorders and many studies also have indicated BACE1 as a possible risk factor for seizures, but not any studies have reported association between BACE1 gene polymorphisms and seizures. Therefore, we investigated the possible association between focal seizures and BACE1 gene polymorphisms in the present study.

METHODS

A total of 162 patients and 211 health controls were enrolled in this study and polymorphisms of BACE1 gene were detected using polymerase chain reaction (PCR)-ligase detection reaction method.

RESULTS

The frequency of genotype AT for BACE1 rs535860 (A>T) was significantly higher (24.1%) in patients compared to controls (14.7%) (OR = 1.836, 95% CI = 1.086-3.102, P = .023). Intriguingly, we only found the significant difference of BACE1 SNP genotype and allele frequency among males but not females. However, no statistically significant results were presented for the genotype distributions of rs525493 (G>T) and rs638405(C>G) polymorphisms between patients and controls.

CONCLUSION

Our study demonstrated there may exist an association between BACE1 rs535860 (A>T) polymorphism and focal seizures in Chinese Han males.