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

Structural connectivity as a predictive factor for perampanel response in patients with epilepsy

OBJECTIVES

This study aimed to identify clinical characteristics that could predict the response to perampanel (PER) and determine whether structural connectivity is a predictive factor.

METHODS

We enrolled patients with epilepsy who received PER and were followed-up for a minimum of 12 months. Good PER responders, who were seizure-free or presented with more than 50 % seizure reduction, were classified separately from poor PER responders who had seizure reduction of less than 50 % or non-responders. A graph theoretical analysis was conducted based on diffusion tensor imaging to calculate network measures of structural connectivity among patients with epilepsy.

RESULTS

106 patients with epilepsy were enrolled, including 26 good PER responders and 80 poor PER responders. Good PER responders used fewer anti-seizure medications before PER administration compared to those by poor PER responders (3 vs. 4; p = 0.042). Early PER treatment was more common in good PER responders than poor PER responders (46.2 vs. 21.3 %, p = 0.014). Regarding cortical structural connectivity, the global efficiency was higher and characteristic path length was lower in good PER responders than in poor PER responders (0.647 vs. 0.635, p = 0.006; 1.726 vs. 1,759, p = 0.008, respectively). For subcortical structural connectivity, the mean clustering coefficient and small-worldness index were higher in good PER responders than in poor PER responders (0.821 vs. 0.791, p = 0.009; 0.597 vs. 0.560, p = 0.009, respectively).

CONCLUSION

This study demonstrated that early PER administration can predict a good PER response in patients with epilepsy, and structural connectivity could potentially offer clinical utility in predicting PER response.

Efficacy and safety of Perampanel in the treatment of post stroke epilepsy: A multicenter, real-world study

Background

Since 2019, Perampanel (PER) has been endorsed in China as an adjunctive treatment for focal seizures, both with and without impaired awareness, and for the transition from focal to bilateral tonic-clonic seizures. Limited research exists regarding the efficacy of PER in treating post-stroke epilepsy (PSE) in China. Empirical studies are essential to guide treatment protocols. We conducted a retrospective study to assess the efficacy and tolerability of PER in 58 PSE patients treated between October 2019 and July 2023.

Method

This study encompassed 58 patients with PSE, treated with PER either as monotherapy or as part of adjunctive therapy, and underwent follow-up for a minimum duration of 6 months. The study assessed changes in seizure frequency, adverse events (AEs), drug retention rate, maintenance dose, and adverse reactions following PER treatment.

Results

The study included 58 PSE patients, with 60.3% males and 39.7% females, ranging in age from 18 to 89, mostly within the 61-70 age group. Ischemic strokes constituted 58.6% of cases, while hemorrhagic strokes accounted for 41.4%. Focal seizures, either with or without impaired awareness, were noted in 62.1% of patients, and a transition from focal to bilateral tonic-clonic seizures was seen in 32.8%. The retention rates for PER at 3 and 6 months stood at 94.8% and 84.5% respectively, and the most commonly administered maintenance dose was 4 mg/day (41.28%). In the adjunctive therapy group, efficacy rates were 66.7% at 3 months and 78.6% at 6 months, compared to 80.0% at 3 months and 85.7% at 6 months in the monotherapy group. In the efficacy analysis, with a criterion of ≥50% reduction in seizure frequency, the overall efficacy rates at 3 and 6 months were 69.1% and 79.6%, respectively. Adverse reactions occurred in 46.6% of patients, primarily involving irritability and somnolence (both 27.6%), with no marked difference in incidence between the adjunctive and monotherapy groups (P > 0.05).

Conclusion

PER exhibits favorable efficacy and tolerability in Chinese PSE patients, possibly at lower doses.

Efficacy and safety of perampanel monotherapy in Chinese patients with focal-onset seizures: A single-center, prospective, real-world observational study

OBJECTIVE

Efficacy and safety of perampanel monotherapy for treating focal-onset seizures (FOS) has been barely studied in China. This observational study aimed to evaluate the efficacy and safety of perampanel monotherapy in treating Chinese patients with FOS.

METHODS

This single-center, prospective, real-world observational study enrolled patients aged ≥4 years with FOS who visited the Epilepsy Out-Patient Clinic of Nanjing Brain Hospital affiliated to Nanjing Medical University from January 2020 to December 2021. All patients were treated with perampanel monotherapy. Seizure-freedom rates after 6 and 12 months of treatment were calculated. Adverse events (AEs) were recorded.

RESULTS

Seventy patients with FOS were enrolled. The mean maintenance perampanel dose was 4.64 ± 1.55 mg/day. The 6- and 12-month retention rates of perampanel monotherapy were 78.6% (55/70) and 70.0% (49/70), respectively. The 6- and 12-month seizure-freedom rates were 69.84% (44/63) and 65.08% (41/63), respectively. Patients with focal to bilateral tonic-clonic seizures had significantly higher 6-month and numerically higher 12-month seizure freedom rates than patients with focal impaired awareness seizures (P = 0.046 and P = 0.204, respectively). Twenty-six (37.1%) patients experienced treatment-emergent AEs, and the most common AE was dizziness. Four (5.7%) patients withdrew from the study due to AEs. No new safety concern was observed.

SIGNIFICANCE

This is the first prospective study on the efficacy and safety of perampanel monotherapy in treating Chinese patients with FOS, and perampanel monotherapy was effective and safe in treating Chinese patients aged ≥4 years with FOS up to 12 months. More multicenter, real-world studies with large sample sizes and longer follow-ups are needed to further evaluate the long-term efficacy and safety of perampanel monotherapy.

Cenobamate in patients with highly refractory focal epilepsy: A retrospective real-world study

PURPOSE

To determine the effectiveness and safety outcomes of cenobamate in a cohort of patients with highly refractory focal epilepsy in routine clinical practice.

METHODS

Observational, retrospective, phase 4 study on subjects receiving cenobamate in three Spanish centers. The primary endpoint was the retention rate at the last follow-up. The main secondary endpoints were the 50%-responder  and seizure-free rates at three months and the last follow-up. Other secondary endpoints were Global Clinical Impressions-Improvement (CGI-I) scores and treatment-emergent adverse events (TEAEs).

RESULTS

Fifty-one patients with highly refractory focal epilepsy with 24.7 years of disease evolution, ten previously tried ASM, and a 23.5% of previous epilepsy surgery were included. The retention rate at the last follow-up was 80.4%. The 50% responder rate in focal seizures at three months was 56.5% (median reduction per month 51%, 0-74.6; p < 0.0001) and in focal to bilateral tonic-clonic seizures was 63.6% (median reduction per month 89%, 0-100; p = 0.022). A total of 54.3% of subjects reported a reduction in the intensity of focal seizures, and 66% manifested clinically significant satisfaction. Cenobamate allowed a significant decrease in concomitant ASM, especially sodium channel blockers. TEAEs were reported in 43.1% of individuals, 85% of whom resolved or improved, with no new safety findings.

CONCLUSION

In this analysis of patients with highly refractory focal epilepsy treated with cenobamate according to standard clinical practice, there was evidence of a high reduction in both seizure frequency and intensity, with a manageable safety profile.

Five-Year Retention of Perampanel and Polytherapy Patterns: 328 Patients From a Single Center in South Korea

BACKGROUND AND PURPOSE

Perampanel (PER) is an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid antagonist used to treat focal and generalized epilepsy. Comprehensive data from real-world settings with long-term follow-ups are still scarce. This study aimed to determine the factors related to PER retention and the polytherapy pattern with PER.

METHODS

We reviewed all patients with epilepsy with a history of PER prescription during 2008-2017 and over a follow-up of >3 years. PER usage patterns and associated factors were analyzed.

RESULTS

Among the 2,655 patients in the cohort, 328 (150 females, 178 males) were enrolled. The ages at onset and diagnosis were 21.1±14.7 years and 25.6±16.1 years (mean±standard deviation), respectively. The age at the first visit to our center was 31.8±13.8 years. Seizure types were focal, generalized, and unknown onset in 83.8%, 15.9%, and 0.3% of patients, respectively. The most common etiology was structural (n=109, 33.2%). The maintenance duration of PER was 22.6±19.2 months (range=1-66 months). The initial number of concomitant antiseizure medications was 2.4±1.4 (range=0-9). The most common regimen was PER plus levetiracetam (n=41, 12.5%). The median number of 1-year seizures before PER usage was 8 (range=0-1,400). A seizure reduction of >50% was recorded in 34.7% of patients (52.0% and 29.2% in generalized and focal seizures, respectively). The 1-, 2-, 3-, 4-, and 5-year retention rates for PER were 65.3%, 50.4%, 40.4%, 35.3%, and 21.5%, respectively. A multivariate analysis indicated that lower age at onset was associated with longer retention (p=0.01).

CONCLUSIONS

PER was safely used in patients with diverse characteristics and was maintained for a long time in a real-world setting, especially in patients with a lower age at onset.

Kainate Receptor Antagonists: Recent Advances and Therapeutic Perspective

Since the 1990s, ionotropic glutamate receptors have served as an outstanding target for drug discovery research aimed at the discovery of new neurotherapeutic agents. With the recent approval of perampanel, the first marketed non-competitive antagonist of AMPA receptors, particular interest has been directed toward 'non-NMDA' (AMPA and kainate) receptor inhibitors. Although the role of AMPA receptors in the development of neurological or psychiatric disorders has been well recognized and characterized, progress in understanding the function of kainate receptors (KARs) has been hampered, mainly due to the lack of specific and selective pharmacological tools. The latest findings in the biology of KA receptors indicate that they are involved in neurophysiological activity and play an important role in both health and disease, including conditions such as anxiety, schizophrenia, epilepsy, neuropathic pain, and migraine. Therefore, we reviewed recent advances in the field of competitive and non-competitive kainate receptor antagonists and their potential therapeutic applications. Due to the high level of structural divergence among the compounds described here, we decided to divide them into seven groups according to their overall structure, presenting a total of 72 active compounds.

Effectiveness of Perampanel as the Only Add-on: Retrospective, Multicenter, Observational Real Life Study on epilepsy patients

OBJECTIVE

Perampanel (PER) is indicated as adjunctive antiseizure medication (ASM) in adolescents and adults with epilepsy. Data from clinical trials show good efficacy and tolerability, while limited information is available on the routine clinical use of PER, especially when used as only add-on treatment.

METHODS

we performed an observational, retrospective, multicenter study on people with focal or generalized epilepsy aged >12 years, consecutively recruited from 52 Italian epilepsy centers. All patients received PER as the only add-on treatment to a background ASM according to standard clinical practice. Retention rate, seizure frequency and adverse events were recorded at 3, 6 and 12 months after PER introduction. Sub-analyses by early or late use of PER and by concomitant ASM were also conducted.

RESULTS

503 patients were included (age 36.5±19.9 years). Eighty-one per cent had focal epilepsy. Overall, the retention rate was very high in the whole group (89% at 12 months) according with efficacy measures. No major differences were observed in the sub-analyses, although patients who used PER as early add-on, as compared with late add-on, more often reached early seizure freedom at 3 months follow-up (66% vs. 53%, p=0.05). Treatment-emergent adverse events occurred in 25%, far less commonly than in PER randomized trials.

SIGNIFICANCE

this study confirms the good efficacy and safety of PER for focal or generalized epilepsy in real-life conditions. We provide robust data about its effectiveness as only add-on treatment even in patients with a long-standing history of epilepsy and previously treated with many ASMs.

Red blood cell distribution width predicts in-hospital mortality in patients with a primary diagnosis of seizures in the ICU: a retrospective database study

Purpose

The aim of this study was to determine the predictive value of red blood cell distribution width (RDW) in patients with a primary diagnosis of seizures admitted to the intensive care unit (ICU) in terms of in-hospital mortality.

Methods

This was a retrospective study of the eICU Collaborative Research Database of adult patients (aged 18–88 years) with a primary diagnosis of seizures in 2014 and 2015. The prognostic value of RDW was investigated using a receiver operating characteristic (ROC) curve, multiple logistic regression model, and net reclassification index (NRI).

Results

We identified 1568 patients who met the inclusion criteria. High RDW was significantly correlated with in-hospital mortality after adjusting for potential confounders with an odds ratio (OR) of 3.513 (95% confidence interval [CI]:1.699–7.266). The area under the ROC curve of RDW for in-hospital mortality was 0.7225. Compared with the prediction of in-hospital mortality using APACHE IV score alone, the continuous NRI with the RDW variable was 0.3507 (95%CI: 0.0584–0.6431, p < 0.05). The length of stay in the ICU of patients with an RDW >14.65% was significantly increased compared to those with normal RDW (log-rank test, p < 0.0001).

Conclusion

RDW width can be useful for prediction of in-hospital mortality in patients with seizures admitted to the ICU, and it provides additional prognostic value beyond the APACHE IV score alone.