Time to prerandomization seizure count design sufficiently assessed the safety and tolerability of perampanel for the treatment of primary generalized tonic-clonic seizures

OBJECTIVE

Static assignment of participants in randomized clinical trials to placebo or ineffective treatment confers risk from continued seizures. An alternative trial design of time to exceed prerandomization monthly seizure count (T-PSC) has replicated the efficacy conclusions of traditionally designed trials, with shorter exposure to placebo and ineffective treatment. Trials aim to evaluate efficacy as well as safety and tolerability; therefore, we evaluated whether this T-PSC design also could replicate the trial's safety and tolerability conclusions.

METHODS

We retrospectively applied the T-PSC design to analyze treatment-emergent adverse events (TEAEs) from a blinded, placebo-controlled trial of perampanel for primary generalized tonic-clonic seizures (NCT01393743). The safety analysis set consisted of 81 and 82 participants randomized to perampanel and placebo arms, respectively. We evaluated the incidences of TEAEs, treatment-related TEAEs, serious TEAEs, and TEAEs of special interest that occurred before T-PSC relative to those observed during the full-length trial.

RESULTS

Of the 67 and 59 participants who experienced TEAEs in the perampanel and placebo arms during full-length trial, 66 (99%) and 54 (92%) participants experienced TEAEs with onset occurring before T-PSC, respectively. When limited to treatment-related TEAEs, 55 of 56 (98%) and 32 of 37 (86%) participants reported treatment-related TEAEs that occurred before T-PSC in the perampanel and placebo arms, respectively. There were more TEAEs after T-PSC with placebo as compared to perampanel (Fisher exact odds ratio = 8.6, p = .035), which resulted in overestimation of the difference in TEAE rate. There was a numerical reduction in serious TEAEs (3/13 occurred after T-PSC, one in placebo and two in perampanel).

SIGNIFICANCE

Almost all TEAEs occurred before T-PSC. More treatment-related TEAEs occurred after T-PSC for participants randomized to placebo than perampanel, which may be due to either a shorter T-PSC or delayed time to TEAE for placebo.

Safety assessment of cenobamate: real-world adverse event analysis from the FAERS database

Objective

This study aims to analyze adverse drug events (ADEs) associated with cenobamate from the FAERS database, covering the third quarter of 2020 to the second quarter of 2023.

Methods

Data related to cenobamate-associated ADEs from the third quarter of 2020 to the second quarter of 2023 were collected. After standardizing the data, various signal quantification techniques, including ROR, MHRA, BCPNN, and MGPS, were employed for analysis.

Results

Among 2535 ADE reports where cenobamate was the primary suspected drug, 94 adverse reactions involving 11 different System Organ Class (SOC) categories were identified through the application of four signal quantification techniques. More specifically, neurological disorders and injuries resultant from complications are frequent adverse reactions associated with cenobamate.

Conclusion

Our research findings align with established results, affirming the favorable safety profile of cenobamate. Effective prevention of adverse reactions induced by cenobamate can be achieved through the establishment of efficient blood concentration monitoring and dose adjustments.

Efficacy and tolerability of perampanel: a Chinese real-world observational study in epilepsy

Purpose

To investigate whether there exists a statistically significant distinction between the effectiveness and tolerance of perampanel (PER) and the number of antiseizure medications (ASMs) that were tried prior to administering PER.

Method

A prospective, observational study was performed at West China Hospital of Sichuan University. The study included patients diagnosed with epilepsy who were prescribed PER and were monitored for a minimum of 6 months. The efficacy of PER was evaluated at 1, 3, 6, and 12-month intervals by examining the retention rate and the 50% response rate. All statistical analyses were conducted using IBM SPSS Statistics version 25 (IBM Corporation, Armonk, New York).

Results

A total of 1,025 patients were identified, of which 836 were included in the analysis. Seven hundred and eighty-nine patients (94.4%) were followed up for a year. The median age of the patients was 29.32 ± 14.06 years, with 45.81% of the patients being male and 17.0% being adolescents. The average duration of epilepsy was 11.22 ± 8.93 years. Overall, PER was discontinued in 49.5% of patients, with the most common reasons being inadequate therapeutic effect and treatment-emergent adverse events (TEAEs). At the 6-month follow-up, the retention rate was 54.2% (454/836), and 39.6% of patients had a 50% response. At the 12-month follow-up, the retention rate was 49.4% (340/789), and 44.5% of patients had a 50% response. Patients who received PER as monotherapy had the highest retention rates (P = 0.034) and 50% response rates (P < 0.001) at any follow-up point. TEAEs were reported in 32.0% of patients, and these led to discontinuation in 15.4% of patients. The most common TEAEs were dizziness and somnolence. There was no significant difference between subgroups (P = 0.57), but there was a significant difference between the dosage of PER and TEAEs (P < 0.001).

Main findings

The study concludes that PER is effective in treating both focal and generalized tonic-clonic seizures. Patients who had fewer previous exposures to ASMs exhibited higher response rates to PER. TEAEs related to PER dosage were more prevalent during the first 3 months of treatment and tended to improve with continued use, ultimately demonstrating favorable long-term tolerability.

The broad-spectrum activity of perampanel: state of the art and future perspective of AMPA antagonism beyond epilepsy

Glutamate is the brain's main excitatory neurotransmitter. Glutamatergic neurons primarily compose basic neuronal networks, especially in the cortex. An imbalance of excitatory and inhibitory activities may result in epilepsy or other neurological and psychiatric conditions. Among glutamate receptors, AMPA receptors are the predominant mediator of glutamate-induced excitatory neurotransmission and dictate synaptic efficiency and plasticity by their numbers and/or properties. Therefore, they appear to be a major drug target for modulating several brain functions. Perampanel (PER) is a highly selective, noncompetitive AMPA antagonist approved in several countries worldwide for treating different types of seizures in various epileptic conditions. However, recent data show that PER can potentially address many other conditions within epilepsy and beyond. From this perspective, this review aims to examine the new preclinical and clinical studies-especially those produced from 2017 onwards-on AMPA antagonism and PER in conditions such as mesial temporal lobe epilepsy, idiopathic and genetic generalized epilepsy, brain tumor-related epilepsy, status epilepticus, rare epileptic syndromes, stroke, sleep, epilepsy-related migraine, cognitive impairment, autism, dementia, and other neurodegenerative diseases, as well as provide suggestions on future research agenda aimed at probing the possibility of treating these conditions with PER and/or other AMPA receptor antagonists.

The safety of perampanel in different disorders and doses: A meta-analysis

PURPOSE

To investigate the safety of perampanel in different disorders and doses.

METHODS

Embase, the Cochrane Library, Medline, and ClinicalTrials.gov were searched from inception to July 2022 for randomized controlled trials (RCTs). The meta-analysis was performed by using Review Manager 5.3 and R 4.2.1 software.

RESULTS

A total of 17 RCTs with 5711 subjects were included in the final analysis. The double-blind treatment phase was from 12 weeks to 48 weeks. Our results showed that 11 adverse events (aggression, ataxia, balance disorder, dizziness, fall, fatigue, irritability, rash, somnolence, vertigo, and weight increase) were statistically significantly associated with perampanel, and 4 of them (ataxia, dizziness, fatigue, and somnolence) showed a clear dose-response relationship. Psychiatric adverse events occurred most frequently among serious treatment-emergent adverse events (TEAEs). At 8 mg/day, seven adverse events (aggression, balance disorder, dizziness, fatigue, irritability, vertigo, and weight increase) occurred more frequently in patients with epilepsy than in patients with other disorders, whereas dose discontinuation rates due to adverse events were lower in patients with epilepsy than in patients with other disorders.

CONCLUSION

The safety profile of perampanel is dependent on diseases and dose. The risk of adverse events was statistically significantly higher, with doses exceeding 4 mg/day. Despite a higher risk of adverse events, patients with epilepsy had a lower perampanel discontinuation rate than patients with other disorders.

Drug-induced fall risk in older patients: A pharmacovigilance study of FDA adverse event reporting system database

Objectives: As fall events and injuries have become a growing public health problem in older patients and the causes of falls are complex, there is an emerging need to identify the risk of drug-induced falls. Methods: To mine and analyze the risk signals of drug-induced falls in older patients to provide evidence for drug safety. The FDA Adverse Event Reporting System was used to collect drug-induced fall events among older patients. Disproportionality analyses of odds ratio (ROR) and proportional reported ratio were performed to detect the adverse effects signal. Results: A total of 208,849 reports (34,840 fall events and 1,898 drugs) were considered. The average age of the included patients was 76.95 ± 7.60 years, and there were more females (64.47%) than males. A total of 258 drugs with positive signals were detected to be associated with drug-induced fall incidence in older patients. The neurological drugs (104, 44.1%) with the largest number of positive detected signals mainly included antipsychotics, antidepressants, antiparkinsonian drugs, central nervous system drugs, anticonvulsants and hypnotic sedatives. Other systems mainly included the circulatory system (25, 10.6%), digestive system (15, 6.4%), and motor system (12, 5.1%). Conclusion: Many drugs were associated with a high risk of falls in older patients. The drug is one of the critical and preventable factors for fall control, and the risk level of drug-induced falls should be considered to optimize drug therapy in clinical practice.

Factors associated with the use and longer duration of seclusion and restraint in psychiatric inpatient settings: a retrospective chart review

Objectives: To examine factors that may affect the use and duration of seclusion and restraint (SR) in psychiatric inpatient settings. Methods: First, multivariable logistic regression analysis was used to examine factors associated with the use of SR in an unmatched case-control study, comparing SR cases and controls. Second, for patients that underwent SR, multivariable linear regression analysis was used to determine factors contributing to the duration of SR. Results: Out of 213 patients, 58 underwent SR. An F00 diagnosis, a history of epilepsy, antipsychotics usage and antidepressants usage were significantly associated with the use of SR (odds ratio = 7.98; 95% CI = 1.11-57.50, odds ratio = 4.89; 95% CI = 1.12-21.36, odds ratio = 4.59; 95% CI = 1.54-13.68 and odds ratio = 0.29; 95% CI = 0.10-0.86, respectively). An F00 and F32 diagnosis significantly extended the duration of SR (coefficient = 13.10; 95% CI = 2.11-24.11 and coefficient = 20.52; 95% CI = 9.68-31.37, respectively). Conclusions: A variety of factors are associated with the use and longer duration of SR. Given the potentially harmful effects of these practices, further studies with larger samples and a wider range of quantitative outcome measures are warranted. Key points An F00 diagnosis, a history of epilepsy and antipsychotics usage may increase the use of SR. Antidepressants may decrease the use of SR. An F00 and F32 diagnosis may extend the duration of SR.

An Evidence-Based Review On The Use Of Perampanel For The Treatment Of Focal-Onset Seizures In Pediatric Patients

Perampanel, a non-competitive AMPA receptor antagonist, is a once-daily oral antiepileptic drug approved for the treatment of focal seizures and primary generalized tonic-clonic seizures in children 12 years of age and over. We conducted a systematic review of the data on perampanel in children and adolescents with focal-onset seizures. We found 21 published papers on the pediatric use of perampanel for focal-onset seizures, including 9 papers on clinical trials and ancillary studies of these trials, of which 2 focused on pharmacokinetics, 1 was a meta-analysis, and 9 were real-life studies (1 was prospective). Perampanel, as an adjunctive treatment for uncontrolled focal-onset seizures, results in an improvement of seizure control with a generally good safety profile. Evidence-based data are currently available for children 12 years of age and over. Higher amounts of perampanel might be required in patients taking enzyme-inducing antiepileptic drugs. The most common adverse events are somnolence, dizziness and behavioral adverse events. The latter seems more frequent in adolescents than in adults and in adolescents with preexisting behavioral comorbidities. Current studies did not identify any short-term impact of perampanel on cognitive functions. Its long half-life allows once-daily administration. Real-life studies further established that a decrease of the dose frequently resolves adverse events, as demonstrated in pivotal studies. Pharmacokinetic and safety studies are still ongoing in the younger population, down to 4 years of age, in order to apply for approval in this age group.

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.

AMPA receptors and perampanel behind selected epilepsies: current evidence and future perspectives

INTRODUCTION

The alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors are the major mediators of glutamate-mediated excitatory neurotransmission, and are critical for synchronization and spread of epileptic activity. Areas covered: AMPA receptor antagonists have been also developed as antiepileptic drugs and perampanel (PER) is the first highly selective, non-competitive AMPA-type glutamate receptor antagonist that is available on the market. It is approved as adjunctive therapy for the treatment of partial-onset seizures with or without secondary generalization, and for primary generalized tonic-clonic seizures in idiopathic generalized epilepsy, in patients aged ≥ 12 years. This article reviews the role of AMPA receptors in the neuronal hyperexcitability underlying epilepsy, the mechanism of action and clinical experience on the anti-seizure activity of PER. Moreover, the rationale for targeting AMPA receptor in specific epileptic disorders, including brain tumor-related epilepsy, mesial temporal lobe epilepsy with/without hippocampal sclerosis, and status epilepticus is evaluated. Finally, the pharmacological rationale for the development of AMPA receptor antagonists in other neurological disorders beyond epilepsy is considered. Expert opinion: Further research aimed at better understanding the pharmacology and blocking mechanism of PER and other AMPA receptor antagonists will drive future development of therapeutic agents that target epilepsy and other neurological diseases.

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.