Adjunctive perampanel in refractory epilepsy: Experience at tertiary epilepsy care center in Tours

The Efficacy and Cognitive Impact of Perampanel Monotherapy in Patients with Self-Limited Epilepsy with Centrotemporal Spikes: A Retrospective Analysis

Objective

The third generation of antiepileptic medication (ASM) perampanel (PER), is mostly used as an add-on treatment for refractory epilepsy patients, and rarely used as a monotherapy. This study aims to observe the efficacy and assess the cognitive effects of PER monotherapy in patients with self-limited epilepsy with centrotemporal spikes (SeLECTS).

Patients and Methods

Through screening, 86 patients who were first diagnosed with SeLECTS and treated with PER monotherapy were included in this study. All patients were followed up at least 12 months, and Evaluated the efficacy and safety of PER by observing the seizures of patients. At the same time, we used the P300 event-related potential (ERP) component and Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) to evaluate the cognitive changes in children before and after treatment with PER.

Results

Ten percent of the children experienced adverse effects, such as dizziness, gait instability, and irritability. The drug retention rate at the last follow-up was 98.83%. Further more, the P300 ERP component and WISC-IV tests were performed no significant difference before and 12 months after PER monotherapy in SeLECTS children.

Conclusion

The third-generation of ASM PER monotherapy had a clear effect in children with SeLECTS. A small dose of PER can control seizures well and has no obvious effect on cognitive development.

The real-world effectiveness and safety of perampanel in Europe: A scoping review

In order to characterize the real-world effectiveness and safety of perampanel during clinical use in Europe, we conducted a structured literature search and scoping review of real-world studies conducted in Europe in adolescents (aged ≥ 12 years) or adults who were prescribed perampanel for focal epilepsy or primary generalized tonic-clonic seizures in the context of idiopathic generalized epilepsy, published between January 2016 and July 2021. We identified 29 relevant studies (20 retrospective and 9 prospective) in 3608 patients; median study duration was 12 months. Most patients (76.1%) were receiving two or more antiseizure drugs (ASDs) when perampanel was initiated. The maintenance perampanel dose ranged from 2 to 16 mg/day (most commonly 6 mg/day). Retention rate at 12 months ranged from 46% to 90.5% (median 71.1%). The proportion of patients who were free of seizures during perampanel ranged from 1.8% to 84.6%, but were consistently below 20% in studies where patients had received an average of ≥5 prior ASDs and above 20% where patients had received an average of <5 prior ASDs. The proportion of patients who achieved ≥50% reduction in seizures during perampanel ranged from 20.0% to 85.7%. Across all studies, the incidence of adverse events (AEs) ranged from 18.2% to 67.4% (median 37.1%) and discontinuation due to AEs from 6.2% to 56% (median 12.5%). Discontinuation rates tended to be higher in UK studies than in studies from Italy or Spain. The most commonly reported individual AEs were dizziness/vertigo (median incidence 13.7%), somnolence (median 11.9%), aggression (median 9.8%), irritability (median 9.1%), and cognitive deficits (median 7.0%). There was no relationship between the overall rate of AEs and perampanel dose, perampanel plasma levels, or number of concomitant medications. Our global overview of European observational studies with perampanel provides evidence that this agent is effective and safe in clinical practice in a range of countries, patients, and settings.

Movement disorders associated with antiseizure medications: A systematic review

New-onset movement disorders have been frequently reported in association with the use of antiseizure medications (ASMs). The frequency of specific motor manifestations and the spectrum of their semiology for various ASMs have not been well characterized. We carried out a systematic review of literature and conducted a search on CINAHL, Cochrane Library, EMBASE, MEDLINE, PsycINFO, and Scopus from inception to April 2021. We compiled the data for all currently available ASMs using the conventional terminology of movement disorders. Among 5123 manuscripts identified by the search, 437 met the inclusion criteria. The largest number of reports of abnormal movements were in association with phenobarbital, valproic acid, lacosamide, and perampanel, and predominantly included tremor and ataxia. The majority of attempted interventions for all agents were discontinuation of the offending drug or dose reduction which led to the resolution of symptoms in most patients. Familiarity with the movement disorder phenomenology previously encountered in relation with specific ASMs facilitates early recognition of adverse effects and timely institution of targeted interventions.

Perampanel add-on therapy for drug-refractory epilepsy: A single-center retrospective study based on 6-month treatment outcomes in Central China

OBJECTIVE

To systematically evaluate the efficacy, tolerability and retention of perampanel (PER) for treating drug-refractory epilepsy (DRE), and to investigate the independent factors affecting efficacy and retention. We hope this will provide clinicians with guidelines for the use of PER to treat patients with DRE.

METHODS

We conducted a single-center retrospective observational study of patients with DRE who received PER as add-on therapy at the Epilepsy Center of the People's Hospital of Henan Province, China, between 2020 Mar. and 2021 Sep. We collected clinical data from these patients. The observation period was 6 months. The observation endpoint is the drug response and retention rate at 6 months of PER use. Regression analyses were used to compare the differences in efficacy and retention rates, respectively.

RESULTS

Clinical data were obtained for 72 patients with DRE (mean duration of treatment: 10.6 months). At 6 months, 25% of patients (n = 18) were seizure free; 18.1% of patients (n = 13) remained seizure free for 6 months after the addition of PER. 22.2% of patients (n = 16) had a response (One of the patients was withdrawn 5 months after adding PER due to financial difficulties). The retention rate of PER at 6 months was 77.8%. Adverse effects tended to be dominated by neuropsychiatric symptoms. Multifactorial logistic regression analysis showed significant differences in whether the baseline seizure frequency exceeded 4 seizures/month (OR = 0.232, 95%CI: 0.077-0.702, p = 0.01) and whether the number of previously failed ASMs exceeded 3 (OR = 0.316; 95%CI:0.109-0.920, p = 0.035). This indicates that the risk of experiencing a nonresponse is higher with a higher baseline seizure frequency as well as with a higher number of previous ASM failures. Therefore, a baseline frequency exceeding four seizures/month and more than three previous ASM failures were independent influencing factors for PER addition treatment for patients with DRE. Multifactorial COX regression showed that patients with DRE due to infection had a lower retention rate (OR = 15.957, 95% CI: 3.692-68.972, P < 0.001) than patients with DRE due to other noninfectious etiologies. Patients with DRE who only had a single seizure type (OR = 0.053, 95% CI:0.006-0.476, P = 0.009), and patients who did not have cognitive impairment (OR = 134.253, 95% CI:5.623-3205.104, P = 0.002) showed longer durations of PER use. Infection-related epilepsy etiology, experiencing multiple types of seizures, and with cognitive impairment were independent influencing factors on PER use retention in patients with DRE.

CONCLUSION

Our study demonstrated the efficacy of PER for reducing seizure frequency in patients with DRE and found significant differences in efficacy and retention rate, respectively. This provides a basis for assessing the expected efficacy and duration of use of PER for patients with DRE.

Psychiatric and Behavioural Side Effects Associated With Perampanel in Patients With Temporal Lobe Epilepsy. A Real-World Experience

Psychiatric and behavioural side effects are common, undesirable effects associated with antiseizure medication use. Temporal lobe epilepsy is the most common focal epilepsy in adults and it is frequently associated with drug resistance. Patients with intractable epilepsy are more likely to have psychiatric and behavioural side effects when taking antiseizure medications and seem to be at higher risk for psychiatric comorbidities. Perampanel is a novel anti-seizure medication approved for focal and generalised epilepsies as add-on therapy. This is a 12-week short-term observational prospective study on people with focal epilepsy consecutively recruited from an Italian tertiary epilepsy centre, aimed to compare incidence and severity of psychiatric and behavioural side effects associated with perampanel use in patients with temporal lobe epilepsy as compared to other focal epilepsies. All patients received add-on perampanel according to indication and clinical judgement. Incidence and severity of psychiatric and behavioural side effects were rated by Neuropsychiatric Inventory Questionnaire. All patients enrolled answered the questionnaire before starting perampanel and after 12 weeks of treatment. We found no significant difference in terms of incidence and severity of psychiatric and behavioural side effects associated with perampanel in patients with temporal lobe epilepsy as compared to other focal epilepsies. In line with the literature, the most common adverse effects were “irritability” for both groups and “aggression” for patients with other focal epilepsies.

Efficacy and tolerability of adjuvant perampanel: an Australian multicenter real-world observational study in refractory focal and generalized epilepsy syndromes

PURPOSE

To explore the efficacy and tolerability of adjuvant perampanel (PER) and their associated risk factors in late add-on drug-resistant epilepsy.

METHOD

Retrospective multicenter 'real-world' observational study. Consecutively identified patients commenced on PER, with mixed epilepsy syndromes, from nine Australian epilepsy centers. Primary efficacy endpoints were at least 50% reduction in seizure frequency (responders), seizure freedom, and retention at 6 and 12 months, following a 3-month titration period. Tolerability endpoints were cessation of PER for any reason, cessation of PER due to treatment-emergent adverse events (TEAE), or cessation due to inefficacy. Outcomes were assessed for a-priori risk factors associated with efficacy and tolerability.

RESULTS

Three-hundred and eighty seven adults were identified and followed up for a median of 12.1 months (IQR 7.0-25.2). Focal epilepsy accounted for 79.6% (FE), idiopathic generalized epilepsy (IGE), 10.3% and developmental epileptic encephalopathy (DEE) 10.1%, of the cohort. All patients had drug-resistant epilepsy, 71.6% had never experienced six months of seizure freedom, and the mean number of antiepileptic medications (AEDs) prior to starting PER was six. At 12 months, with missing cases classified as treatment failure, retention was 40.0%, responder 21.7%, and seizure freedom 9.0%, whereas, using last outcome carried forward (LOCF), responder and seizure freedom rates were 41.3% and 14.7%, respectively. Older age of epilepsy onset was associated with a marginal increase in the likelihood of seizure freedom at 12-month maintenance (OR 1.04, 95% CI 1.02, 1.06). Male sex (adjusted OR [aOR] 2.06 95% CI 1.33, 3.19), lower number of prior AEDs (aOR 0.84, 95% CI 0.74, 0.96) and no previous seizure-free period of at least 6-month duration (aOR 2.04 95% CI 1.21, 3.47) were associated with retention. Perampanel combined with a GABA receptor AED was associated with a lower responder rate at 12 months but reduced cessation of PER. The most common TEAEs were neuropsychiatric (18.86%), followed by dizziness (13.70%), and sleepiness (5.68%).

CONCLUSIONS

Adjuvant PER treatment, even in late-add on drug-resistant epilepsy is an effective and well-tolerated treatment for drug-resistant epilepsy.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

An evaluation of the effectiveness of perampanel in people with epilepsy who have previously undergone resective surgery and/or implantation of a vagal nerve stimulator

About 30% of people with epilepsy (PWE) are drug-resistant. Those with focal seizures may be suitable for epilepsy surgery. Those not amenable to resective surgery can be considered for vagus nerve stimulation (VNS). However, after operative procedures, around 50% of patients continue to experience seizures. A multi-center retrospective study assessing perampanel effectiveness and tolerability for PWE who have undergone surgical resection and/or VNS implantation was performed. The primary outcome was ≥50% reduction in seizure frequency while secondary outcomes included side effects (SEs), dose-related effectiveness, and toxicity. The median perampanel dose was 6 mg. Only one PWE became seizure free. A ≥50% decrease in seizure frequency was observed in 52.8% of the post-resection group and 16.9% of the VNS group (p < 0.001), while SEs were seen in 44.8% and 41.1%, respectively. Perampanel doses greater than 8 mg led to better response in both groups, especially in the post-VNS cohort. SEs were not dose-related and the safety profile was similar to previous observational studies. Perampanel can be beneficial in these two super-refractory epilepsy groups, particularly in PWE with seizures after surgical resection. Doses of more than 8 mg appear to be well tolerated and may be more effective than lower doses in PWE after surgical interventions.

Perampanel as add-on therapy in epilepsies with known etiology: A single center experience with long-term follow-up

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PER showed good efficacy for the treatment of epilepsies with known etiology.

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PER showed greater efficacy in patients with epilepsy due to a focal brain lesion .

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PER was globally well tolerated with a good profile of safety.

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EEG pattern , expression of a structural epilepsy, correlates with a better response.

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EEG pattern might help in the choice of correct antiseizure medication.

We report a retrospective monocentric study performed on 63 patients affected by epilepsy with known etiology, receiving perampanel as add-on therapy with at least 12-month follow-up. The purpose of our study was to evaluate efficacy and tolerability of perampanel in this group of epilepsies. Patients were classified into 2 groups based on the presence/absence of a single focal brain lesion on MRI, as epilepsy etiology: 48 subjects were affected by focal lesional epilepsy and 15 by non-focal lesional epilepsy. The retention rate was 76.2% and 53.9% at 12 and 24 months respectively. At 12 months, at least 40% of patients resulted responders, with a significant reduction in seizure frequency (p = 0.01), confirmed at 24 months. Considering epilepsy etiology, we found a better PER response in patients with focal lesional epilepsy. A significant correlation was observed between responder rates and EEG pattern. Only 30% of patients reported mild-moderate adverse events. Efficacy and tolerability of PER, in our study, are in line with the results reported in other real-world studies. Our data suggest the possibility of better PER response in patients with focal brain lesions, which indicates that this drug could be a therapeutic option in this population.

Improved irritability, mood, and quality of life following introduction of perampanel as late adjunctive treatment for epilepsy

OBJECTIVE

The objective of this study was to evaluate the efficacy and tolerability of perampanel (PER) in late adjunctive treatment of focal epilepsy. We assessed outcomes 1) according to patients' clinical profiles and the broad mechanism of action (MoA) of concomitant antiepileptic drugs (AEDs) and 2) the effects of PER on adverse events, irritability, mood, and quality of life (QOL).

METHODS

Consecutive patients commenced on PER at two epilepsy centers in Melbourne, Australia were identified. A nested cohort underwent detailed prospective assessment, while the remainder were retrospectively analyzed. Six- and 12-month efficacy endpoints were at least a 50% reduction in seizure frequency (responders) and complete seizure freedom. The prospective cohort underwent standardized validated questionnaires at 0, 1, 3, 6, and 12 months using the modified semi-structured seizure interview (SSI), Liverpool Adverse Events Profile (LAEP), Quality of Life in Epilepsy-Patient-Weighted (QOLIE-10-P), Neurological Disorders Depression Inventory Epilepsy (NDDI-E), and an Irritability Questionnaire.

RESULTS

One hundred sixty patients were followed for a median of 6 months: the mean number of prior AEDs was 6, 99% had drug-resistant epilepsy, and 72% had never experienced a prior seizure-free period of at least 6 months (=continuously refractory epilepsy). Perampanel was associated with responder and seizure freedom rates of 30.6% and 9.4% at 6 months and 19.4% and 4.4% (5.6% adjusted for the titration period) at 12 months. Having "continuously refractory epilepsy" was associated with a reduced likelihood of seizure freedom at 6 months (5% vs. 30%; p = 0.001) and 12 months (3% vs. 13%; p = 0.058). Quality of Life in Epilepsy-Patient-Weighted, irritability, and NDDI-E showed mean improvement at 6 months from baseline.

SIGNIFICANCE

Even when used as late add-on adjunctive therapy in patients with highly refractory focal epilepsy, PER can result in 12-month seizure freedom of 5.6%. The likelihood of seizure freedom was associated with prior "continuous medication refractoriness". Six months after introduction of PER patients reported improved mood, QOL, and decreased irritability.

The impact of perampanel treatment on quality of life and psychiatric symptoms in patients with drug-resistant focal epilepsy: An observational study in Italy

An observational, prospective study has been conducted to evaluate the effects of adjunctive treatment with perampanel (PER) on psychological functioning and quality of life (QoL) in patients with drug-resistant focal epilepsy. Fifty-six adult patients treated with PER in addition to antiepileptic drugs (AEDs) were recruited in 2 Italian Epilepsy Centers. Irritability in Adult Patients with Epilepsy (I-EPI), Quality of Life in Epilepsy (QOLIE-31), Beck Depression Inventory II (BDI-II), and State-Trait Anxiety Inventory Y-1 and Y-2 (STAI) questionnaires were administered at baseline and 3 and 6 months after the treatment onset. Adverse events (AEs) were collected during the observational 6 months period. Retention rate of treatment with PER was 82.1% at 3 months and 64.3% at 6 months. Thirteen patients reported a significant seizure frequency reduction, and one seizure freedom case was observed after 4 months of PER treatment. Perampanel was stopped because of inefficacy or paradoxical effects in 28.6% of cases and because of AEs in 7.1%. The peak dose was not associated with discontinuation probability. Irritability, QoL, depression, trait, and state anxiety did not change significantly during the PER therapy. A tendency of association between higher level of irritability at baseline and PER discontinuation was found. The results of this observational study have shown that the addition of PER to AEDs may improve seizure control, does not increase levels of irritability, depression, and anxiety, and does not reduce patients' QoL. This study also confirms the importance of a comprehensive clinical assessment, including psychiatric symptoms evaluation before offering a new treatment, to improve therapy compliance.

Efficacy and tolerability of perampanel in patients with genetic generalized epilepsy (GGE): A retrospective, single-center study from the United Arab Emirates (UAE)

•52.4% achieved seizure freedom at six months from baseline in our cohort of PWE from the UAE.•38.1% achieved ≥50% reduction in seizure frequency at six months from baseline.•90.5% remained on perampanel treatment beyond the six-month period.•33.3% maintained perampanel monotherapy beyond six months.•9.5% discontinued perampanel treatment due to treatment-induced adverse events.

Preliminary evidence about irritability in patients with epilepsy treated by perampanel as first add-on therapy compared to levetiracetam and valproic acid

Aims

Irritability has been described as a frequent adverse event in patients affected by epilepsy and treated with perampanel (PER), levetiracetam (LEV), and less frequently with valproic acid (VPA). Since the questionnaire for irritability (I‐EPI) is a validated instrument to measure this psychiatric manifestation in patients affected by epilepsy, in this study we aimed at investigating the effect of PER as first add‐on therapy on I‐EPI. Moreover, we compared the effectiveness and I‐EPI scores obtained at 12‐month follow‐up visits in patients treated by PER, LEV, or VPA in order to measure irritability as a consequence of these treatments.

Methods

We collected data from 17 patients treated by PER, 16 patients treated by LEV, and 16 patients under VPA treatment followed for 12 months.

Results

We did not document significant changes of I‐EPI questionnaire between baseline and follow‐up in the PER group. As concerning the comparison of I‐EPI among PER, LEV, and VPA groups, we documented lower global scores in PER than both LEV (P < 0.05) and VPA (P < 0.05) groups. Moreover, patients under PER treatment showed lower scores than LEV and VPA (P < 0.05) in I‐EPI items measuring the gentle personality, anxiety of having epileptic seizures in front of others, and irritability in thinking that they can have an epileptic seizure.

Conclusions

This retrospective study described a stable and possibly lower degree of irritability in patients starting PER than LEV and VPA treatments, although we documented the comparable effectiveness of PER, LEV, and VPA as first add‐on treatments in patients affected by uncontrolled epileptic seizures. However, the small sample of patients included in this study and the absence of I‐EPI scores obtained at baseline visits in LEV and VPA groups require further investigations to confirm this preliminary evidence.

Efficacy and tolerability of perampanel in children and adolescents with pharmacoresistant epilepsy: The first real-world evaluation in Asian pediatric neurology clinics

AIM

This study investigated the efficacy and safety of perampanel (PER) adjunctive therapy in pediatric patients with epilepsy whose seizures are pharmacoresistant to existing antiepileptic drugs.

METHODS

A clinical retrospective study was conducted from 2016 to 2017 in the pediatric neurology clinic at a tertiary children's hospital. We reviewed the data obtained from 66 children whose seizures were pharmacoresistant to more than two antiepileptic drugs, and could be followed up for a minimum of 3 months after PER adjunctive therapy initiation. The efficacy was estimated by the PER response rate at 3-, 6-, and 12-month follow-up evaluations, and adverse events were also recorded.

RESULTS

The rate of seizure reduction of >50% was 30.3%, 37.5%, and 34.7% for all seizure types at 3, 6, and 12 months, in which 7.6%, 8.9%, and 14.3% of the patients became seizure-free at these time points, respectively. No significant differences were found between enzyme-inducing and nonenzyme-inducing antiepileptic drugs in combination with PER with regard to the responder rate. Five patients with Dravet syndrome were included in the study. Four of them (80%) exhibited 50% seizure reduction at the last visit, at which point, two patients (40.0%) were seizure-free. The retention rate was 51% at 12 months. Adverse events were documented in 25 patients (35.7%) and led to PER discontinuation in eight patients (12.1%). The most common adverse events comprised irritability, skin rash, dizziness, and somnolence; however, all were transient and successfully managed after PER dose reduction or discontinuation.

CONCLUSION

The current data support the value of adjunctive PER in child and adolescent patients with pharmacoresistant epilepsy in daily clinical practice. Perampanel was efficacious and generally well-tolerated as an add-on treatment for epilepsy.

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.

Perampanel: Does it have broad-spectrum potential?

This article reviews the profile of perampanel, a novel noncompetitive α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor antagonist, and its role as a potential broad-spectrum antiepileptic drug in the treatment of epilepsy. For this narrative review, data were collected using specified search criteria. Articles reporting the evidence for perampanel's efficacy from preclinical models, phase 3 clinical studies, observational studies, and descriptive evidence were included. AMPA receptors play a key role in mediating the action of glutamate at the excitatory synapse. Preclinical research showed the AMPA receptor blockade to constitute a promising target for antiepileptic drug therapy. In animal models, perampanel proved to be protective against seizures and reduce seizure severity and duration. Four phase-3 randomized controlled trials (3 in patients with focal seizures and one in primary generalized tonic-clonic seizures in idiopathic generalized epilepsy) have been completed. In focal (partial) onset seizures, perampanel (4, 8, and 12 mg) significantly reduced seizure frequency per 28 days (23.3%-28.8% vs 12.8%; P < .01) and responder rates (≥50% reduction in seizures) (28.5%-35.3% vs 19.3%; P < .05) compared with placebo. In primary generalized tonic-clonic seizures, perampanel 8 mg resulted in greater reduction in seizure frequency per 28 days (-76.5% vs -38.4%; P < .0001) and responder rate (64.2% vs 39.5%; P = .0019) than placebo. The efficacy, safety, and tolerability of perampanel have been reproduced in real-world clinical practice, and the agent has been shown to be effective in other epilepsy syndromes. Perampanel is a potentially broad-spectrum antiepileptic drug with a novel mechanism of action that may be a useful addition for patients with epilepsy with various seizure types. The availability of novel antiepileptic drugs for epilepsy treatment enables more individualized treatment for these patients.

Efficacy and tolerability of perampanel and levetiracetam as first add-on therapy in patients with epilepsy: A retrospective single center study

Perampanel (PER) is a third generation antiepileptic drug (AED), recently approved as add-on therapy in both focal and generalized seizures. Levetiracetam (LEV) is a second generation AED, widely used in patients with epilepsy because of its favorable safety and efficacy profiles. Perampanel and LEV treatments have been associated with the occurrence of similar adverse events (AEs) (sleepiness, irritability, depression, anxiety, aggressiveness). The aim of the present retrospective single center study was to verify the efficacy and tolerability of PER and LEV used as first add-on therapy in patients with epilepsy affected by secondarily generalized seizures. We collected data from 15 patients treated with PER and 26 patients treated with LEV and followed at our site with follow-up visits at 3, 6, and 12months. This retrospective study documented the comparable efficacy of PER and LEV as first add-on treatments in patients affected by uncontrolled secondarily generalized seizures. However, more patients withdrawn LEV because of AEs compared with PER at the 3- and 12-month follow-up visits. The better tolerability of PER observed in this study could be related to the low therapeutic dose of PER prescribed when it is used as first adjunctive treatment for better controlling secondarily generalized seizures.

Preliminary Asian experience of using perampanel in clinical practice

Background

To analyze the efficacy and safety of perampanel over a 3-month period in a sample of Asian people with epilepsy.

Methods

The efficacy and safety of perampanel as an adjunctive therapy for patients with epilepsy were retrospectively reviewed and analyzed. Patients were categorized according to seizure type, concomitant antiepileptic drug usage, and perampanel dosage.

Results

A total of 210 patients were included in the study and 131 patients completed 3 months of perampanel treatment. The average dosage of perampanel was 5.31 mg/day, and the 50% responder rate (≥50% seizure frequency reduction) in all patients was 45.8%, with a 27.5% seizure-free rate. For focal seizures, focal to bilateral tonic-clonic seizures, and primary generalized seizures, the 50% responder rates were respectively 29.4%, 49.5%, and 36.4%. In total, 39.5% of patients experienced adverse events within 3 months of observation period, and the rate of drug withdrawal due to adverse events was 8.6%. Dizziness, ataxia, irritability/aggression were the most common adverse events.

Conclusions

The efficacy and safety of perampanel in a real-world setting with Asian patients is comparable to that in clinical trials that have included fewer Asian patients.

One-Year Retention Study of Adjunctive Perampanel Treatment in Epilepsy Patients

OBJECTIVES

Perampanel is a recently introduced antiepileptic drug (AED) with a unique action mechanism of noncompetitive and selective α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid antagonist. Because of delayed approval of perampanel in most Asian countries, there is limited information on the clinical usefulness of perampanel in the Asian population. We performed a retrospective analysis of retention rate, seizure outcome, and adverse events for perampanel treatment in South Korea.

METHODS

This was a retrospective, single-center, 1-year observational study. A total of 137 epilepsy patients (86 men, 51 women; age, 17-86 years) who were treated with perampanel as an adjunctive treatment were included. Perampanel was administered at a starting dose of 2 mg/d, and optimal-dose adjustments were made according to individual clinical responses. Efficacy and tolerability were analyzed during a 1-year follow-up.

RESULTS

The overall retention rate was 71.3% at the 6-month follow-up and 61.0% at the 1-year follow-up. Retention rates were similar between patients with 1 concomitant AED and those taking 2 or more concomitant AEDs. The most common adverse event was somnolence, followed by dullness and psychiatric reactions, and the presence of psychiatric comorbidity was significantly associated with the development of psychiatric adverse reactions.

CONCLUSIONS

We showed that the retention rate and adverse events for adjunctive perampanel treatment in the Korean population were comparable with those in Western countries. Our study also suggests that adjuvant perampanel treatment may be effective in patients taking a higher number of concomitant AEDs and that psychiatric comorbidity may be a risk factor for perampanel-induced psychiatric reactions.

Comparing Safety and Efficacy of "Third-Generation" Antiepileptic Drugs: Long-Term Extension and Post-marketing Treatment

Four "third-generation" antiepileptic drugs (AEDs) were approved for adjunctive treatment of refractory focal onset seizures during the past 10 years. Long-term efficacy and safety of the drugs were demonstrated in large extension studies and in reports of subgroups of patients not studied in pivotal trials. Reviewing extension study and post-marketing outcome series for the four newer AEDs-lacosamide, perampanel, eslicarbazepine acetate and brivaracetam-can guide clinicians in treating and monitoring patients. AED extension studies evaluate treatment retention, drug tolerability, and drug safety during individualized treatment with flexible dosing and thus provide information not available in rigid pivotal trials. Patient retention in the studies ranged from 75 to 80% at 1 year and from 36 to 68% at 2-year treatment intervals. Safety findings were generally similar to those of pivotal trials, with no major safety risks identified and with several specific adverse drug effects, such as hyponatremia, reported. The third-generation AEDs, some through new mechanisms and others with improved tolerability compared to related AEDs, provide new options in efficacy and tolerability.

Psychiatric and behavioral side effects of antiepileptic drugs in adults with epilepsy

PURPOSE

Psychiatric and behavioral side effects (PBSEs) are common, undesirable effects associated with antiepileptic drug (AED) use. The objective of the study was to compare the PBSE profiles of older and newer AEDs in a large specialty practice-based sample of patients diagnosed with epilepsy.

METHODS

As part of the Columbia and Yale AED Database Project, we reviewed patient records including demographics, medical history, AED use, and side effects for 4085 adult patients (age: 18 years) newly started on an AED regimen. Psychiatric and behavioral side effects were determined by patient or physician report in the medical record, which included depressive mood, psychosis, anxiety, suicidal thoughts, irritability, aggression, and tantrum. Significant non-AED predictors of PBSE rate were first determined from 83 variables using logistic regression. Predictors were then controlled for in the comparison analysis of the rate of PBSEs and intolerable PBSEs (PBSEs that led to dosage reduction or discontinuation) between 18 AEDs.

RESULTS

Psychiatric and behavioral side effects occurred in 17.2% of patients and led to intolerability in 13.8% of patients. History of psychiatric condition(s), secondary generalized seizures, absence seizures, and intractable epilepsy were associated with increased incidence of PBSE. Levetiracetam (LEV) had the greatest PBSE rate (22.1%). This was statistically significant when compared with the aggregate of the other AEDs (P<0.001, OR=6.87). Levetiracetam was also significantly (P<0.001) associated with higher intolerability rate (17.7%), dose decreased rate (9.4%), and complete cessation rate (8.3%), when compared with the aggregate of the other AEDs. Zonisamide (ZNS) was also significantly associated with a higher rate of PBSE (9.7%) and IPBSE (7.9%, all P<0.001). On the other hand, carbamazepine (CBZ), clobazam (CLB), gabapentin (GBP), lamotrigine (LTG), oxcarbazepine (OXC), phenytoin (PHT), and valproate (VPA) were significantly associated with a decreased PBSE rates (P<0.001). Carbamazepine, GBP, LTG, PHT, and VPA were also associated with lower IPBSE rates when compared individually with the aggregate of other AEDs. All other AEDs were found to have intermediate rates that were not either increased or decreased compared with other AEDs. When each AED was compared to LTG, only CBZ had a significantly lower PBSE rate. The main limitations of this study were that the study design was retrospective and not blinded, and the AEDs were not randomly assigned to patients.

CONCLUSIONS

Psychiatric and behavioral side effects occur more frequently in patients taking LEV and ZNS than any other AED and led to higher rates of intolerability. Lower PBSE rates were seen in patients taking CBZ, CLB, GBP, LTG, OXC, PHT, and VPA. Our findings may help facilitate the AED selection process.

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.

Use of perampanel in children and adolescents with Lennox-Gastaut Syndrome

AIM

Report the use of perampanel treatment in children with Lennox-Gastaut syndrome (LGS).

METHOD

We conducted a prospective study of 13 LGS patients (seven male; mean age, 12.8years) treated with adjunctive perampanel therapy. Perampanel was initiated at 2mg/day and titrated to a median maximum dose of 6mg/day.

RESULTS

After a mean follow-up duration of 10.8months (range, 1-24months), nine patients (69.2%) were responders (≥50% reduction in total seizure frequency) and nine (69.2%) were rated by their physician as "much improved" or "very much improved". Four patients (30.8%) discontinued perampanel due to the lack of efficacy (n=2) and seizure aggravation (n=2). No patients discontinued due to other adverse events (AEs). AEs were reported for six patients (46.2%) and comprised decreased activity/social interaction (n=3), behavior disturbance with agitation (n=2), and/or fatigue (n=2). All AEs became manageable after perampanel dosing was decreased. Improvements in cognitive function and/or behavior were reported for seven patients (53.8%). Introduction of perampanel allowed the dose reduction and/or discontinuation of other treatments in seven patients (53.8%).

INTERPRETATION

Perampanel was efficacious and generally well tolerated as an adjunctive treatment for seizures associated with LGS, supporting further research in this area.

Retention of perampanel in adults with pharmacoresistant epilepsy at a single tertiary care center

RATIONALE

Observational data on antiepileptic drugs (AEDs) inform about their use in clinical practice. We describe our clinical experience with perampanel (PER) in a large UK tertiary epilepsy center.

METHODS

Adults initiated on PER between October 2012 and March 2015 were followed until they discontinued PER or 10 September 2016. Data on epilepsy syndrome, duration, seizure types, concomitant and previous AED use, PER dosing, efficacy and side effects were recorded. Efficacy was categorized as temporary or ongoing (at last follow-up) seizure freedom, ≥50% seizure reduction, or other benefit (e.g. No convulsions or daytime seizures). These categories were mutually exclusive except for people with temporary seizure freedom.

RESULTS

391 received a PER prescription, five of whom never took it. No follow-up data were available for ten. 83% had focal epilepsy. People were prescribed PER in addition to 1-7 (Interquartile range [IQR] 2, 2, 3) AEDs and had previously used up to 18 (IQR 5, 7, 10) AEDs. Total exposure was 639patient/years. Retention rates were 60.4% at one year, 48.3% at two years, and 42.7% at three years. 19 (5%) people reported seizure free periods lasting at least six months. A ≥50% reduction in seizures lasting at least six months was reported by 76 people (20%), and marked improvement for ≥6months was seen in 52 (14%). Five (1%) were taken off other AEDs and continued on PER monotherapy for 4-27months. Seizures were aggravated in 57 (15%). Somatic side effects were reported by 197 (52%), mostly CNS. Mood changes, irritability or challenging behavior were reported by 137 (36%). PER was discontinued by 211 (56%) due to adverse effects (39%), inefficacy (26%), or both (35%). No idiosyncratic adverse events were seen.

CONCLUSION

PER resulted in some benefit in 40% of those exposed. Adverse effects on mental health and on balance were common and should be discussed with people before initiating PER.

A two-year retrospective evaluation of perampanel in patients with highly drug-resistant epilepsy and cognitive impairment

PURPOSE

The objective of this work was to review systematically the efficacy and tolerability of perampanel (PER) in residential patients of an epilepsy center.

METHOD

We adopted an industry-independent noninterventional retrospective evaluation on the basis of the paper and electronic records complemented by personal information on the part of the treating neurologists. All patients (N=26, 15 females, mean age: 30, range 21-55years) started on PER from its introduction to the market in September 2012 until December 15th 2013 were included. Evaluation was carried out after 6, 12, and 24months of PER treatment. Changes in seizure frequency were calculated as the number of seizures during three months on PER compared to a three-month baseline period. The Clinical Global Impression Scale served as an instrument to record changes in seizure intensity beyond numerical values. Adverse effects were documented by means of the Liverpool Adverse Events Profile.

RESULTS

Most patients had structural or metabolic epilepsy, 2 patients suffered from Lennox-Gastaut syndrome, 2 from other symptomatic generalized epilepsy. All patients had grade III drug-resistant epilepsy. All patients had additional cognitive deficits of different degree. The retention rates were 61.5% after 6months, 46.2% after 12months, and 42.3% after 24months. The responder rates were 11.5% after 6months, 23.1% after 12months, and 7.7% after 24months. Partial responders (positive CGI and/or seizure reduction <50%) included, the respective values were 26.9%, 38.5%, and 23.1%. Only 1 patient was seizure free at 12months (but not at 24months). A loss of efficacy in the second year of treatment was suspected but the decrease of the responder rate could also be ascribed to a number of different circumstances. Adverse effects in the psychiatric field like irritability, aggression, increased sensitivity, and suicidal ideation/behavior occurred in 50% of the patients. They were the main reason to discontinue PER.

CONCLUSIONS

After one year of treatment PER showed reasonable efficacy in a particularly difficult-to-treat population. Psychiatric adverse effects forced discontinuation in many cases.