Pharmacotherapy for tonic-clonic seizures

Enhancing analgesia in acute renal colic pain: a randomized controlled trial of gabapentin adjunct to ketorolac-based regimen

Background

Renal colic is characterized by severe pain that is highly disabling. Gabapentin, an antiepileptic medication, is often recommended as a first-line therapy for neuropathic pain. However, its effectiveness in managing somatic pain, which is defined as the result of activity by pain receptors in the deep tissues, such as renal colic pain, is not as well-established.

Method

A phase 3 randomized clinical trial was conducted to evaluate the adjuvant analgesic effects of gabapentin on acute renal colic pain. Eligible patients participated in the study via random allocation to the control or gabapentin groups using the block randomization method. All patients received a shared regimen of ketorolac and rescue morphine as the conventional analgesic treatment for renal colic pain. Gabapentin was added as an adjuvant analgesic for the gabapentin group.

Result

A total of 63 individuals with an average age of 41.35 ± 13.08, were enrolled and completed the study. At the time of admission, there were no significant differences between the baseline characteristics of two groups, with exception of weight. The gabapentin group showed a significantly higher percentage of patients with pain severity of less than 5 after 60 and 90 min, as well as a significantly lower percentage of morphine rescue requirement and total morphine intake (mg) and mg/kg.

Conclusion

In cases of acute renal colic, gabapentin significantly decreases both the amount of morphine required and the degree of pain, indicating that it may be a useful adjutant to standard analgesic regimens. Treatment regimens that include gabapentin may help individuals manage their pain and become less reliant on opioids.

Clinical Trial Registration

https://irct.behdasht.gov.ir/trial/56066, identifier: IRCT20200322046833N2.

Antiseizure Medications and Sudden Unexpected Death in Epilepsy: An Updated Review

Sudden unexpected death in epilepsy (SUDEP) is responsible for most epilepsy-related deaths. It is mainly related to unwitnessed nocturnal convulsions, either focal to bilateral or generalised tonic-clonic seizures (TCS). Targeted preventive strategies are currently lacking as underlying mechanisms are largely unknown. Antiseizure medications (ASMs) modulate SUDEP risk through seizure reduction, but it is yet undetermined whether individual ASMs or other medications could also influence the internal SUDEP cascade. Seizure detection devices (SDD) may offer an alternative strategy by preventing TCS from being unwitnessed. Here, we critically evaluated the current evidence on the influence of ASMs, non-epilepsy concomitant drugs and SDD on SUDEP occurrence. We found no robust evidence for the effect of starting ASMs on SUDEP beyond TCS control, but we found some indications of a protective effect for polytherapy. We found no signs that specific ASMs exert a risk for SUDEP. One study suggested a possible protective effect of levetiracetam requiring further investigation. Only a few small studies addressed the association between non-epilepsy concomitant drugs and SUDEP, with no consistent effect for psychotropic medications and one more extensive study suggesting a lower risk among statin users. We only found indirect evidence indicating a protective effect for enhancing nocturnal supervision without explicitly addressing the impact of SDD on SUDEP occurrence. Further work is needed to explore the potential of ASMs and other interventions to modulate SUDEP risk, and they should accurately account for TCS frequency, polypharmacy and markers of non-adherence.

Identification of New Antiseizure Medication Candidates in Preclinical Animal Studies

Epilepsy is a multifactorial neurologic disease that often leads to many devastating disabilities and an enormous burden on the healthcare system. Until now, drug-resistant epilepsy has presented a major challenge for approximately 30% of the epileptic population. The present article summarizes the validated rodent models of seizures employed in pharmacological researches and comprehensively reviews updated advances of novel antiseizure candidates in the preclinical phase. Newly discovered compounds that demonstrate antiseizure efficacy in preclinical trials will be discussed in the review. It is inspiring that several candidates exert promising antiseizure activities in drug-resistant seizure models. The representative compounds consist of derivatives of hybrid compounds that integrate multiple approved antiseizure medications, novel positive allosteric modulators targeting subtype-selective γ-Aminobutyric acid type A receptors, and a derivative of cinnamamide. Although the precise molecular mechanism, pharmacokinetic properties, and safety are not yet fully clear in every novel antiseizure candidate, the adapted approaches to design novel antiseizure medications provide new insights to overcome drug-resistant epilepsy.

Long-term open-label perampanel: generalized tonic-clonic seizures in idiopathic generalized epilepsy

Objective

Assess the longer‐term efficacy and safety of adjunctive perampanel (up to 12 mg/day) in patients aged ≥12 years with generalized tonic–clonic (GTC) seizures from the Open‐label Extension (OLEx) Phase of Study 332 to determine whether responses obtained during the Core Study are maintained during long‐term treatment.

Methods

Patients with GTC seizures previously enrolled in a randomized placebo‐controlled trial of perampanel could enter an OLEx Phase comprising 6‐week blinded conversion (during which patients previously randomized to placebo‐switched to perampanel) and up to 136‐week maintenance periods (maximum perampanel dose of 12 mg/day). A 4‐week follow‐up period was completed by all patients after the last on‐treatment visit during the OLEx. We assessed seizure frequency outcomes from preperampanel baseline and the Core Study Pre‐randomization Phase, retention rates, doses selected, and treatment‐emergent adverse events (TEAEs).

Results

Overall, 138 patients entered the OLEx. Median percent reductions in GTC seizures per 28 days from preperampanel were 77% (Weeks 1‐13) and 90% (Weeks 40‐52). Retention rates were 88% (6 months) and 75% (12 months). Seizure‐freedom rates were maintained for at least 2 years regardless of prior treatment received during the Core Study. Most common modal daily dose was >4‐8 mg/day (n = 93). Across the Core and OLEx Phases, 120 (87%) patients experienced TEAEs; the most common was dizziness.

Significance

Perampanel was generally well‐tolerated, and the TEAEs reported here are consistent with the known safety profile of perampanel. Perampanel offers a long‐term treatment option for patients (aged ≥12 years) with GTC seizures.

Sustained seizure freedom with adjunctive perampanel in patients with convulsive seizures: Post hoc analysis of open-label extension studies 307 and 332

OBJECTIVE

Since increased mortality rates have been associated with convulsive seizures, it is important to achieve seizure control in these patients. Here, we report post hoc analyses to assess long-term seizure-freedom rates with adjunctive perampanel in patients (aged ≥ 12 years) with refractory focal to bilateral tonic-clonic seizures (FBTCS) or generalized tonic-clonic seizures (GTCS) who participated in open-label extension (OLEx) studies.

METHODS

Patients with focal-onset seizures, with/without FBTCS, who completed double-blind, Phase III Studies 304, 305, or 306 could enter OLEx Study 307 (16-week blinded Conversion; 256-week Maintenance). Patients with GTCS who completed the double-blind phase of Study 332 could enter the OLEx Phase (6-week blinded Conversion; 136-week Maintenance). Maximum perampanel dose: 12 mg/day. Seizure-freedom rates for up to 24 months were assessed in perampanel-treated patients who achieved seizure freedom during the double-blind studies to determine if their seizure-free status was maintained during the OLEx. In addition, to ensure any patients who only achieved seizure freedom during the OLEx were captured, seizure-freedom rates were also assessed in all patients who achieved and maintained a seizure-free status for a period of at least six consecutive months at any time during the double-blind and/or OLEx studies; some of these patients may have received placebo during the double-blind study but only their time on perampanel is included in the seizure-free analysis. Univariate and multivariate analyses were used to identify predictive factors for achieving seizure freedom for at least 6 months. Treatment-emergent adverse events (TEAEs) were assessed.

RESULTS

Overall, 53.8% (n = 42/78) of patients who received perampanel and were FBTCS free during the double-blind studies remained seizure free for up to 24 months during Study 307, and 31.6% (n = 6/19) of patients who were GTCS free during the double-blind phase of Study 332 remained seizure free for up to 24 months during the OLEx Phase. Over 40% (FBTCS, 41.5% [n = 197/475]; GTCS, 52.9% [n = 73/138]) of patients were seizure free for a period of at least six consecutive months. Multivariate analysis showed that the best predictors of achieving seizure freedom from FBTCS for at least 6 months were lower baseline seizure frequency (p = 0.0014) and absence of enzyme-inducing anti-seizure medications at baseline (p = 0.0056); multivariate analysis was not conducted for GTCS since only one variable was identified as a significant predictor of seizure freedom in the univariate analysis (lower baseline seizure frequency). Perampanel was generally well tolerated with no new safety signals identified. The most common TEAE was dizziness. For both seizure types, 10% or fewer seizure-free patients discontinued perampanel due to TEAEs.

CONCLUSIONS

These results suggest that adjunctive perampanel may be a suitable long-term treatment option for patients (aged ≥ 12 years) with convulsive seizures to achieve and maintain seizure freedom.

Mortality and causes of death among people with convulsive epilepsy in northwestern China

OBJECTIVE

We analyzed mortality and causes of death among people with convulsive epilepsy in rural areas of northwestern China.

METHODS

We established a population-based prospective cohort of people with convulsive epilepsy in an epilepsy prevention and management program in rural northwestern China from January 2012 to December 2013. A uniform cause of death questionnaire was used to obtain detailed information on participants who died during the follow-up until December 2016. We calculated the standardized mortality ratios (SMRs) and proportional mortality rate for major causes of death. Cox proportional hazards regression analysis was used to investigate the risk factors associated with mortality.

RESULTS

Among 4296 people with convulsive epilepsy, 216 died during a median follow-up of 59 months. The overall mortality rate was 10.9 per 1000 person-years, and the overall SMR was 2.0. Accidents (25.5%) ranked first in the cause of death, followed by status epilepticus (SE) (22.9%), probable sudden unexpected death in epilepsy (SUDEP) (22.7%), cerebrovascular disease (13.0%), and cardiovascular disease (6.5%). Drowning (10.6%), motor vehicle accidents (13.6%), and falls (4.6%) were the major causes of death by accidents. Female participants had a reduced risk of death from accidents with the hazard ratio (HR) of 0.3 (95% confidence interval (CI): 0.1-0.6). A high risk of death from cerebrovascular disease (HR: 7.2; 95% CI: 2.1-23.6) was found in participants with an onset age of epilepsy older than 16 years.

SIGNIFICANCE

The risk of death from convulsive epilepsy in rural northwestern China is twice that of the general population. Accidents, SE, and SUDEP are the leading putative causes of death. Educating people with epilepsy in different regions may help reduce death-related events.

Towards realizing the vision of precision medicine: AI based prediction of clinical drug response

Accurate and individualized prediction of response to therapies is central to precision medicine. However, because of the generally complex and multifaceted nature of clinical drug response, realizing this vision is highly challenging, requiring integrating different data types from the same individual into one prediction model. We used the anti-epileptic drug brivaracetam as a case study and combine a hybrid data/knowledge-driven feature extraction with machine learning to systematically integrate clinical and genetic data from a clinical discovery dataset (n = 235 patients). We constructed a model that successfully predicts clinical drug response [area under the curve (AUC) = 0.76] and show that even with limited sample size, integrating high-dimensional genetics data with clinical data can inform drug response prediction. After further validation on data collected from an independently conducted clinical study (AUC = 0.75), we extensively explore our model to gain insights into the determinants of drug response, and identify various clinical and genetic characteristics predisposing to poor response. Finally, we assess the potential impact of our model on clinical trial design and demonstrate that, by enriching for probable responders, significant reductions in clinical study sizes may be achieved. To our knowledge, our model represents the first retrospectively validated machine learning model linking drug mechanism of action and the genetic, clinical and demographic background in epilepsy patients to clinical drug response. Hence, it provides a blueprint for how machine learning-based multimodal data integration can act as a driver in achieving the goals of precision medicine in fields such as neurology.

Clinical Management of Drug Resistant Epilepsy: A Review on Current Strategies

Drug resistant epilepsy (DRE) is defined as the persistence of seizures despite at least two syndrome-adapted antiseizure drugs (ASD) used at efficacious daily dose. Despite the increasing number of available ASD, about a third of patients with epilepsy still suffer from drug resistance. Several factors are associated with the risk of evolution to DRE in patients with newly diagnosed epilepsy, including epilepsy onset in the infancy, intellectual disability, symptomatic epilepsy and abnormal neurological exam. Pharmacological management often consists in ASD polytherapy. However, because quality of life is driven by several factors in patients with DRE, including the tolerability of the treatment, ASD management should try to optimize efficacy while anticipating the risks of drug-related adverse events. All patients with DRE should be evaluated at least once in a tertiary epilepsy center, especially to discuss eligibility for non-pharmacological therapies. This is of paramount importance in patients with drug resistant focal epilepsy in whom epilepsy surgery can result in long-term seizure freedom. Vagus nerve stimulation, deep brain stimulation or cortical stimulation can also improve seizure control. Lastly, considering the effect of DRE on psychologic status and social integration, comprehensive care adaptations are always needed in order to improve patients' quality of life.

Assessment of the long-term efficacy and safety of adjunctive perampanel in tonic-clonic seizures: Analysis of four open-label extension studies

OBJECTIVE

This post hoc analysis evaluated long-term efficacy and safety in patients with focal to bilateral tonic-clonic seizures (FBTCS) or generalized tonic-clonic seizures (GTCS) who entered open-label extension (OLEx) studies to receive long-term adjunctive perampanel.

METHODS

Patients aged 12 years and older who completed phase II or III randomized, double-blind, placebo-controlled studies could enter an OLEx study, each comprising a blinded conversion period followed by an open-label maintenance period (32-424 weeks; maximum perampanel dose = 12 mg/d). Exposure, seizure outcomes, and treatment-emergent adverse events (TEAEs) were analyzed.

RESULTS

Baseline characteristics were generally balanced between patients with FBTCS (n = 720) and GTCS (n = 138). Mean (standard deviation) cumulative duration of perampanel exposure was 102.3 (70.3) weeks (FBTCS) and 83.9 (38.4) weeks (GTCS). Retention rates were 50.0% for up to 4 years (FBTCS) and 49.2% for up to 2 years (GTCS). Across OLEx treatment durations, median reductions in seizure frequency per 28 days were 66.7% (FBTCS) and 80.6% (GTCS). Fifty percent and 75% responder and seizure-freedom rates were 59.5%, 45.3%, and 18.4%, respectively (FBTCS), and 72.5%, 51.5%, and 16.7%, respectively (GTCS). Efficacy was sustained for up to 4 years (FBTCS) and up to 3 years (GTCS), even when accounting for early dropouts. TEAE incidence was highest during Year 1 (FBTCS, 85.3%; GTCS, 86.2%); most common were dizziness and somnolence. During Year 1, serious TEAEs were reported in 81 (11.3%; FBTCS) and 10 (7.2%; GTCS) patients. TEAEs were consistent with the known safety profile of perampanel; no new safety signals were identified with long-term treatment.

SIGNIFICANCE

This post hoc analysis suggests long-term (up to 4 years) adjunctive perampanel (up to 12 mg/d) is efficacious and well tolerated in patients (aged 12 years and older) with FBTCS or GTCS.

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.

Prevention of sudden unexpected death in epilepsy: current status and future perspectives

Introduction: Sudden unexpected death in epilepsy (SUDEP) affects about 1 in 1000 people with epilepsy, and even more in medically refractory epilepsy. As most people are between 20 and 40 years when dying suddenly, SUDEP leads to a considerable loss of potential life years. The most important risk factors are nocturnal and tonic-clonic seizures, underscoring that supervision and effective seizure control are key elements for SUDEP prevention. The question of whether specific antiepileptic drugs are linked to SUDEP is still controversially discussed. Knowledge and education about SUDEP among health-care professionals, patients, and relatives are of outstanding importance for preventive measures to be taken, but still poor and widely neglected.Areas covered: This article reviews epidemiology, pathophysiology, risk factors, assessment of individual SUDEP risk and available measures for SUDEP prevention. Literature search was done using Medline and Pubmed in October 2019.Expert opinion: Significant advances in the understanding of SUDEP were made in the last decade which allow testing of novel strategies to prevent SUDEP. Promising current strategies target neuronal mechanisms of brain stem dysfunction, cardiac susceptibility for fatal arrhythmias, and reliable detection of tonic-clonic seizures using mobile health technologies.Abbreviations: AED, antiepileptic drug; CBZ, carbamazepine; cLQTS, congenital long QT syndrome; EMU, epilepsy monitoring unit; FBTCS, focal to bilateral tonic-clonic seizures; GTCS, generalized tonic-clonic seizures; ICA, ictal central apnea; LTG, lamotrigine; PCCA, postconvulsive central apnea; PGES, postictal generalized EEG suppression; SRI, serotonin reuptake inhibitor; SUDEP, sudden unexpected death in epilepsy; TCS, tonic-clonic seizures.

Rapidity of CNS Effect on Photoparoxysmal Response for Brivaracetam vs. Levetiracetam: A Randomized, Double-blind, Crossover Trial in Photosensitive Epilepsy Patients

INTRODUCTION

Both levetiracetam (LEV) and brivaracetam (BRV) eliminate the electroencephalogram photoparoxysmal response (PPR) in the human phase IIa photosensitivity model of epilepsy. The physiochemical properties of BRV differ from those of LEV, having higher potency and lipophilicity plus 10- to 15-fold greater affinity for synaptic vesicle glycoprotein 2A.

OBJECTIVE

We compared the rapidity of the effects of both drugs in the central nervous system (CNS) of patients with photosensitive epilepsy using time to PPR elimination post-intravenous infusion as a pharmacodynamic endpoint.

METHODS

Using a randomized, double-blind, two-period, balanced, crossover design, we tested patients with photosensitive epilepsy with equipotent milligram doses of intravenous LEV 1500 mg versus BRV 100 mg post-15-min intravenous infusion (part 1) and post-5-min intravenous infusion (part 2, same doses). Eight patients per part were deemed sufficient with 80% power to determine a 70% reduction for intravenous BRV:LEV intrapatient time ratio to PPR elimination, with a 0.05 two-sided significance level. Plasma antiseizure medicine concentrations were measured using liquid chromatography/mass spectrometry.

RESULTS

Nine patients [six women; mean age 27.8 years (range 18-42)] completed the study; seven of these participated in both parts 1 and 2. In 31 of 32 instances, patients experienced PPR elimination. In mixed-effects model time analysis, BRV eliminated PPRs more quickly than did LEV (median 2 vs. 7.5 min, respectively). However, no statistically significant difference in BRV:LEV time ratio to PPR elimination was observed for two of our multiple primary outcomes: for the 15-min infusion alone (p = 0.22) or the 5-min infusion alone (p = 0.11). However, BRV was faster when we excluded an outlier patient in part 1 (p = 0.0016). For our remaining primary outcome, parts 1 and 2 data combined, the median intrapatient BRV:LEV time ratio was 0.39 [95% confidence interval (CI) 0.16-0.91], i.e., PPR elimination was 61% faster with BRV, p = 0.039. PPR was completely eliminated in ≤ 2 min in 11 patients with BRV and in four patients with LEV. No period or carryover effects were seen. No serious or severe adverse effects occurred. At PPR elimination (n = 16), median plasma [BRV] was 250 ng/mL (range 30-4100) and median plasma [LEV] was 28.35 μg/mL (range 1-86.7).

CONCLUSION

Outcome studies directly comparing LEV and BRV are needed to define the clinical utility of the response with BRV, which was several minutes faster than that with LEV.

CLINICAL TRIALS

ClinTrials.gov Identifier = NCT03580707; registered 07-09-18.

Accidental injuries in patients with generalized tonic-clonic seizures. A multicenter, observational, cross-sectional study (QUIN-GTC study)

PURPOSE

Patients with epilepsy have a higher risk of accidental injuries. The aim of this study was to determine the incidence of accidental injuries and quality of life in patients with epilepsy and generalized tonic-clonic seizures and their association with patient-related factors.

METHODS

This is an observational, cross-sectional, multicenter study of patients with epilepsy and primary generalized tonic-clonic seizures and/or focal to bilateral tonic-clonic seizures in the routine clinical practice of epilepsy clinics. In a single visit, demographic and clinical data and information on the type and severity of injuries were collected, and patients' quality of life was evaluated with the QOLIE-10 questionnaire.

RESULTS

In total, 406 patients with a median age of 41.1 years (range: 13-87) were included; 47.5% were women. Age at onset of tonic-clonic seizures was 25.4 (range: 0-83) years. Epileptic seizures were primary tonic-clonic (67.2%), focal to bilateral tonic-clonic (32.8%), focal with impairment of awareness (23.6%), focal without impairment of awareness (13.5%), absences (14.8%), and myoclonic (9.6%). Etiology was symptomatic or with unknown etiology focal (42.9%), genetic generalized (36.9%), symptomatic or with unknown etiology generalized (18.0%), and others (2.2%). The number of generalized tonic-clonic seizures in the last 12 months was as follows: 1 (41.9%), 2-5 (42.4%), and >5 (15.8%). Antiepileptic treatment at the time of the visit was monotherapy in 44.1% of the patients. The most commonly used drugs were levetiracetam (45.1%), valproate (20.7%), lamotrigine (20.0%), and perampanel (18.7%). In total, 59.6% of the patients had experienced at least one accidental injury associated with tonic-clonic seizures in the last 12 months, the most common being head injuries (35.5%), dental injuries (4.9%), burns (4.9%), and fractures (3.9%). A total of 25.1% had suffered at least one serious injury. The multiple logistic regression model showed that the factors associated with suffering an injury were the following: etiology (symptomatic or with unknown etiology focal and genetic generalized vs. symptomatic or with unknown etiology generalized, p = 0.0008 and p = 0.0077, respectively), number of seizures in the last year (2-5 vs. 1, p = 0.0115; >5 vs. 1, p = 0.0004), and psychiatric comorbidities (p = 0.0151). Patients with injuries had a worse quality of life than patients without injuries, according to the overall QOLIE-10 score (p = 0.0003).

CONCLUSIONS

More than half of the patients had accidental injuries related with seizures. Symptomatic or with unknown etiology focal epilepsy and genetic generalized epilepsy, >1 seizure in the last year, and concomitant psychiatric disease are the risk factors associated with accidental injuries in patients with tonic-clonic seizures, with the consequent worsening of quality of life.

Adjunctive levetiracetam in the treatment of Chinese and Japanese adults with generalized tonic-clonic seizures: A double-blind, randomized, placebo-controlled trial

Objective

To assess the efficacy, safety, and tolerability of adjunctive levetiracetam (LEV) in Chinese and Japanese adults with generalized tonic-clonic (GTC) seizures (N01159; NCT01228747).

Methods

This double-blind, randomized, placebo-controlled, multicenter phase III trial comprised: 4-week retrospective and 4-week prospective baseline, 12-week dose-adjustment, and 16-week evaluation periods. Chinese and Japanese patients ≥16 years old with idiopathic generalized, symptomatic generalized, or undetermined epilepsy with GTC seizures received a single-blind placebo during the prospective baseline, and then were randomized 1:1 to placebo or LEV 1,000 mg/day administered twice daily. Patients reporting GTC seizures up to week 8 had the LEV dosage increased to 3,000 mg/day. The primary efficacy variable was percent reduction from combined baseline in GTC seizures/week during the 28-week treatment period.

Results

Overall, 251 patients were randomized (208 from China; 43 from Japan); 141 (56.2%) completed the 28-week treatment period. Least-squares mean percent reduction from combined baseline in GTC seizures/week (treatment period) was placebo 12.6% versus LEV 68.8% (95% confidence interval, 44.0-68.2; p < 0.0001). GTC seizure frequency reduction occurred in both patients with idiopathic and symptomatic generalized epilepsy. The 50% responder rate (treatment period) was placebo 28.4% versus LEV 77.8%. Freedom from GTC seizures (evaluation period) was placebo 3.1% versus LEV 29.6%. Incidence of treatment-emergent adverse events (TEAEs; treatment period) was placebo 52.0% versus LEV 57.1%; most frequently nasopharyngitis, protein in urine, decreased platelet count, and pyrexia. Incidence of TEAEs leading to discontinuation was 4.8% versus 3.2%; incidence of serious TEAEs was 3.2% versus 0.8% for placebo and LEV, respectively; 3 patients taking placebo died versus none taking LEV.

Significance

In this trial, adjunctive LEV 1,000-3,000 mg/day was effective in reducing GTC seizure frequency in Chinese and Japanese patients ≥16 years old with GTC seizures. Seizure reduction occurred in both patients with idiopathic and symptomatic generalized epilepsy. LEV was well tolerated in this population.

Perampanel in routine clinical use in idiopathic generalized epilepsy: The 12-month GENERAL study

OBJECTIVE

To analyze the effectiveness and tolerability of perampanel across different seizure types in routine clinical care of patients with idiopathic generalized epilepsy (IGE).

METHODS

This multicenter, retrospective, 1-year observational study collected data from patient records at 21 specialist epilepsy units in Spain. All patients who were aged ≥12 years, prescribed perampanel before December 2016, and had a confirmed diagnosis of IGE were included.

RESULTS

The population comprised 149 patients with IGE (60 with juvenile myoclonic epilepsy, 51 generalized tonic-clonic seizures [GTCS] only, 21 juvenile absence epilepsy, 10 childhood absence epilepsy, 6 adulthood absence epilepsy, and one Jeavons syndrome). Mean age was 36 years. The retention rate at 12 months was 83% (124/149), and 4 mg was the most common dose. At 12 months, the seizure-free rate was 59% for all seizures (88/149); 63% for GTCS (72/115), 65% for myoclonic seizures (31/48), and 51% for absence seizures (24/47). Seizure frequency was reduced significantly at 12 months relative to baseline for GTCS (78%), myoclonic (65%), and absence seizures (48%). Increase from baseline seizure frequency was seen in 5.2% of patients with GTCS seizures, 6.3% with myoclonic, and 4.3% with absence seizures. Perampanel was effective regardless of epilepsy syndrome, concomitant antiepileptic drugs (AEDs), and prior AEDs, but retention and seizure freedom were significantly higher when used as early add-on (after ≤2 prior AEDs) than late (≥3 prior AEDs). Adverse events were reported in 50% of patients over 12 months, mostly mild or moderate, and irritability (23%), somnolence (15%), and dizziness (14%) were most frequent.

SIGNIFICANCE

In routine clinical care of patients with IGE, perampanel improved seizure outcomes for GTCS, myoclonic seizures, and absence seizures, with few discontinuations due to adverse events. This is the first real-world evidence with perampanel across different seizure types in IGE.

Spotlight on perampanel in the management of seizures: design, development and an update on place in therapy

Purpose

Perampanel is a first-in-class antiepileptic medication approved for the treatment of partial (focal) seizures, and as adjunctive treatment for primarily generalized tonic–clonic seizures. The pharmacology, efficacy data, adverse-effect profile, pharmacokinetics and place in therapy are reviewed.

Summary

Perampanel is indicated for use in patients with epilepsy who are 12 years of age or older. It is the first medication designed specifically to be a non-competitive antagonist at post-synaptic α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors. Efficacy in refractory seizures has been established, and ongoing efficacy demonstrated by post-marketing data. The drug is completely absorbed, and exhibits a half-life that allows for once-daily administration in doses up to 12 mg/day. Drug interactions are minimal, but increased doses may be necessary when given with strong inducers of cytochrome P450 enzymes, including when perampanel is co-administered with other antiepileptics that exhibit this property. The most common adverse effects noted in both clinical trials and post-marketing are dizziness and somnolence. Psychiatric and behavioral adverse events have been documented in both adult and pediatric patients, including those with no corresponding diagnostic history.

Conclusion

Perampanel is a novel adjunctive antiepileptic medication that is an effective option for adolescents and adults with partial seizures, and primarily generalized tonic–clonic seizures uncontrolled with other medications.

Topiramate-associated sexual dysfunction: A systematic review

INTRODUCTION

Sexual pharmacotoxicity renders patients with epilepsy at a risk for sexual dysfunction (SD). This study is aimed to analyze the relationship between sexual function and topiramate to avoid topiramate-associated SD.

METHODS

A systematic review following the PRISMA guidelines was performed to elucidate any SD occurrence in patients receiving topiramate.

RESULTS

A total of 17 publications were reviewed. Based on limited polytherapy observational studies, the frequency of self-reported topiramate-associated SD, libido disorder, and orgasmic disorder in patients with polytherapy was 9.0%, 9.0%, and 2.6%, respectively (grade C evidence). Female patients mainly had anorgasmia, whereas male patients principally had erectile dysfunction. The daily dose of topiramate in patients with SD was within the recommended dose. Sexual adversity usually occurred from 4weeks after topiramate use but favorably subsided without eventful complications after topiramate substitution or dose reduction in all patients.

CONCLUSIONS

Topiramate can elicit different patterns of SD, especially anorgasmia in women and erectile dysfunction in men, even with a therapeutic dose. Detailed drug education and careful monitoring are necessary to maximize sexual health, especially in persons undergoing polytherapy and with other risks for SD. Moreover, a rapid response, such as substitution or reduction of the dose, is suggested when SD occurs during its use.

Efficacy and tolerability of adjunctive brivaracetam in patients with prior antiepileptic drug exposure: A post-hoc study

Brivaracetam (BRV), a selective, high-affinity ligand for synaptic vesicle protein 2A, is a new antiepileptic drug (AED) for adjunctive treatment of focal (partial-onset) seizures in adults with epilepsy. This post-hoc analysis was conducted to explore the efficacy of adjunctive BRV in patients with prior levetiracetam (LEV) exposure and whether changes in efficacy were related to the similar mechanism of action of these two drugs. Data were pooled from three Phase III studies (NCT00490035; NCT00464269; NCT01261325) of adults with focal seizures taking 1-2 AEDs who received placebo or BRV 50-200mg/day without titration over a 12-week treatment period. Patients taking concomitant LEV at enrollment were excluded from this analysis. Patients were categorized by their status of prior exposure to LEV, carbamazepine (CBZ), topiramate (TPM), or lamotrigine (LTG), to investigate any consistent trend towards reduced response in AED-exposed subgroups compared to AED-naïve subgroups, regardless of the mechanism of action. Study completion rates, percent reduction from baseline in focal seizure frequency over placebo, ≥50% responder rates, and tolerability were evaluated for each subgroup. A total of 1160 patients were investigated. Study completion rates were similar in the AED-exposed subgroups and AED-naïve subgroups. In subgroups with (531 patients) or without (629 patients) prior LEV exposure, ≥50% responder rates for each dose of BRV compared with placebo were generally higher among the LEV-naïve subgroups than the previously LEV-exposed subgroups. LEV-exposed subgroups receiving BRV doses ≥50mg/day showed greater ≥50% responder rates than those receiving placebo. Similar results were observed for CBZ, TPM, and LTG. Previous treatment failure with commonly prescribed AEDs (LEV, CBZ, TPM, or LTG) is associated with a reduced response to BRV irrespective of the mechanism of action. Hence, this post-hoc analysis indicates that previous treatment failure with LEV does not preclude the use of BRV in patients with epilepsy.

Lacosamide for uncontrolled primary generalized tonic-clonic seizures: An open-label pilot study with 59-week extension

OBJECTIVE

Assess the safety of adjunctive lacosamide for the treatment of uncontrolled primary generalized tonic-clonic seizures in patients (16-65 years) with primary generalized (genetic) epilepsy (PGE).

METHODS

An open-label pilot safety study (SP0961; NCT01118949), comprising 12 weeks' historical baseline, 4 weeks' prospective baseline, 3 weeks' titration (target: 400mg/day adjunctive lacosamide) and 6 weeks' maintenance. Patients who continued to the extension study (SP0962; NCT01118962) then received ≤59 weeks of flexible treatment (100-800mg/day lacosamide with flexible dosing of concomitant antiepileptic drugs). The primary outcomes for SP0961 were the mean change (±standard deviation) in absence seizure or myoclonic seizure days per 28days from prospective baseline to maintenance; for SP0962, the incidence of treatment-emergent adverse events (TEAEs) and withdrawals because of TEAEs.

RESULTS

Of the 49 patients who enrolled, 40 (82%) completed the pilot study and 9 discontinued (5 because of adverse events). Of the 39 patients who continued to the extension study, 10 discontinued (2 owing to TEAEs) and 29 (74%) completed the study. During the pilot study, patients reported a reduction in mean (±standard deviation) absence and myoclonic seizure days per 28days (-0.37±4.80, -2.19±5.80). Reductions were also observed during the extension study (-2.38±5.54, -2.78±6.43). Five patients in SP0961 and 2 patients in SP0962 experienced TEAEs of new or increased frequency of absence seizures or myoclonic seizures. The most common TEAEs during SP0961 were dizziness (39%) and nausea (27%), and during SP0962 were dizziness (26%) and upper respiratory tract infection (26%).

CONCLUSIONS

The safety profile of adjunctive lacosamide was similar to that previously published. Adjunctive lacosamide did not systematically worsen absence or myoclonic seizures, and appears to be well tolerated in patients with PGE.

Perampanel: A Review in Drug-Resistant Epilepsy

Perampanel (Fycompa®), an orally-active, selective, noncompetitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist, is a first-in-class antiepileptic drug (AED) offering the convenience of once-daily administration. In the EU and US, perampanel is approved in patients with epilepsy aged ≥12 years for the adjunctive treatment of primary generalized tonic-clonic seizures (GTCS) and partial-onset seizures (POS; with or without secondary generalization). In phase III trials of 17 or 19 weeks' duration, add-on perampanel ≤12 mg/day significantly improved seizure control in patients aged ≥12 years who were experiencing either primary GTCS or POS (with or without secondary generalization), despite ongoing treatment with stable dosages of one to three AEDs. Improvements in seizure control were maintained for up to 2 years in extensions of these core studies. Perampanel also provided sustained seizure control for up to ≈4 years in an extension of two phase II studies in patients aged ≥18 years with drug-resistant POS. Adjunctive perampanel therapy was generally well tolerated. Treatment-emergent adverse events were most commonly CNS-related (e.g. dizziness, somnolence, fatigue and irritability) and dose-related; however, most were of mild to moderate intensity. Clinical experience with perampanel is accumulating, although comparative studies and pharmacoeconomic data that could assist in positioning it relative to other AEDS that are approved and/or recommended as adjunctive therapy are lacking. Nonetheless, on the basis of its overall clinical profile and unique mechanism of action, perampanel is a useful additional adjunctive treatment option for patients with drug-resistant POS, with or without secondary generalization, and primary GTCS.

[Current possibilities of treatment of generalized convulsive seizures]

Current possibilities of treatment of generalized convulsive seizures are presented. Progress in the field of pharmacotherapy of epilepsy allowed to introduce new antiepileptic drugs (AED). Some of them are modified AED with higher efficacy or better tolerability and others represent a generation of new drugs with different mechanisms of action. Perampanel, an agonist of AMPA-receptors, is a new drug approved in more than 40 countries, including Russia. At present, the use of some AED is limited by the high risk of sudden death (sudden unexpected death in epilepsy (SUDEP)). SUDEP is a common cause of death directly associated with epilepsy, with the highest frequency in patients with active epilepsy. Subtherapeutic concentrations of SED in the serum of SUDEP patients may be the consequence of inadequate treatment and low compliance to treatment that causes the development of pseudoresistant seizures and, hence, the higher risk of SUDEP. At the same time, AED per se play an important role in the modification of functions of the autonomic nervous system and may induce disturbances of heart rate and conductivity.

"Herbal seizures"--atypical symptoms after ibogaine intoxication: a case report

Introduction

Misuse of various new psychotropic substances such as ibogaine is increasing rapidly. Knowledge of their negative side effects is sparse.

Case presentation

We present a case of intoxication with the herbal substance ibogaine in a 22-year-old white man. After taking a cumulative dose of 38 g (taken in two doses), he developed visual memories, nausea and vomiting. He developed a generalized tonic–clonic seizure with additional grand mal seizures. He was treated with midazolam and levetiracetam. Extended drug screenings and computed tomography and magnetic resonance imaging findings were all negative.

Conclusions

Knowledge of the side effects of ibogaine has mainly come from reports of cardiovascular complications; seizures are rarely mentioned and experimental findings are inconsistent. It seems that ibogaine acts like a proconvulsive drug at high doses.

Perampanel for tonic-clonic seizures in idiopathic generalized epilepsy A randomized trial

OBJECTIVE

To assess efficacy and safety of adjunctive perampanel in patients with drug-resistant, primary generalized tonic-clonic (PGTC) seizures in idiopathic generalized epilepsy (IGE).

METHODS

In this multicenter, double-blind study (ClinicalTrials.gov identifier: NCT01393743; funded by Eisai Inc.), patients 12 years or older with PGTC seizures and IGE were randomized to placebo or perampanel during a 4-week titration period (perampanel up titrated from 2 to 8 mg/d, or highest tolerated dose) and 13-week maintenance period. The primary endpoint was percent change in PGTC seizure frequency per 28 days (titration plus maintenance vs baseline). The key secondary endpoint (primary endpoint for European Union registration) was 50% PGTC seizure responder rate (patients achieving $50% reduction in PGTC seizure frequency; maintenance vs baseline). Treatment-emergent adverse events were monitored.

RESULTS

Of 164 randomized patients, 162 comprised the full analysis set (placebo, 81; perampanel, 81). Compared with placebo, perampanel conferred a greater median percent change in PGTC seizure frequency per 28 days (238.4%vs 276.5%; p , 0.0001) and greater 50%PGTC seizure responder rate (39.5% vs 64.2%; p 5 0.0019). During maintenance, 12.3% of placebo treated patients and 30.9%of perampanel-treated patients achieved PGTC seizure freedom. For the safety analysis (placebo, 82; perampanel, 81), the most frequent treatment-emergent adverse events with perampanel were dizziness (32.1%) and fatigue (14.8%).

CONCLUSIONS

Adjunctive perampanel was well tolerated and improved control of drug-resistant PGTC seizures in patients with IGE.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that adjunctive perampanel reduces PGTC seizure frequency, compared with placebo, in patients with drug-resistant PGTC seizures in IGE.

The role of carbonic anhydrase in the pathogenesis of vascular calcification in humans

Carbonic anhydrases are a group of isoenzymes that catalyze the reversible conversion of carbon dioxide into bicarbonate. They participate in a constellation of physiological processes in humans, including respiration, bone metabolism, and the formation of body fluids, including urine, bile, pancreatic juice, gastric secretion, saliva, aqueous humor, cerebrospinal fluid, and sweat. In addition, carbonic anhydrase may provide carbon dioxide/bicarbonate to carboxylation reactions that incorporate carbon dioxide to substrates. Several isoforms of carbonic anhydrase have been identified in humans, but their precise physiological role and the consequences of their dysfunction are mostly unknown. Carbonic anhydrase isoenzymes are involved in calcification processes in a number of biological systems, including the formation of calcareous spicules from sponges, the formation of shell in some animals, and the precipitation of calcium salts induced by several microorganisms, particularly urease-producing bacteria. In human tissues, carbonic anhydrase is implicated in calcification processes either directly by facilitating calcium carbonate deposition which in turn serves to facilitate calcium phosphate mineralization, or indirectly via its action upon γ-glutamyl-carboxylase, a carboxylase that enables the biological activation of proteins involved in calcification, such as matrix Gla protein, bone Gla protein, and Gla-rich protein. Carbonic anhydrase is implicated in calcification of human tissues, including bone and soft-tissue calcification in rheumatological disorders such as ankylosing spondylitis and dermatomyositis. Carbonic anhydrase may be also involved in bile and kidney stone formation and carcinoma-associated microcalcifications. The aim of this review is to evaluate the possible association between carbonic anhydrase isoenzymes and vascular calcification in humans.

Prevention of generalized tonic-clonic seizures in refractory focal epilepsy: a meta-analysis

OBJECTIVES

Secondary generalized tonic-clonic seizures (SGTCS) are among the most severe forms of seizures, and the main risk factor for sudden unexpected death in epilepsy (SUDEP). Whether some antiepileptic drugs (AEDs) might be more efficacious than others on SGTCS in patients with drug-resistant focal epilepsy thus represents an important clinical issue for which no data are currently available.

METHODS

We performed a meta-analysis of randomized controlled trials of adjunctive AED in which information on efficacy outcomes (i.e., responder rate and/or frequency per 28 days relative to baseline) were available both for all seizure types and for SGTCS. The primary analysis evaluated the efficacy of AEDs on all types of seizure and on SGTCS by comparing the responder rates for AED and for placebo.

RESULTS

Responder rate was available both for all seizure types and for SGTCS in 13 of the 72 eligible trials, evaluating 7 AEDs. Only three AEDs--lacosamide, perampanel and topiramate--showed greater efficacy than placebo. However, confidence intervals of relative risks overlapped for all AEDs but pregabalin, which demonstrated significantly lower efficacy than lacosamide, perampanel, and topiramate. Moreover, there was a nonsignificant trend toward a lower relative risk of responder rate for SGTCS than for all seizure types, which appeared related to a greater response to placebo for this outcome.

SIGNIFICANCE

Indirect comparison of AEDs using randomized placebo-controlled add-on trials does not support robust differences between AEDs to prevent SGTCS. Alternative designs for evaluation of therapeutic interventions in patients at risk for SGTCS-related complications are required.