perampanel and Status-Epilepticus

Status epilepticus (SE) is a neurological emergency necessitating rapid seizure control to prevent long-term consequences. Perampanel (PER) is a novel selective, noncompetitive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA) receptor antagonist that demonstrated efficacy and safety in lithium-pilocarpine models of SE; however, data in humans are limited. This systematic review was performed to assess the efficacy and safety of PER in patients with SE, RSE, and SRSE.. We searched MEDLINE (accessed through PubMed), Embase, Scopus, Cochrane Library, and ClinicalTrials.gov from inception until May 30, 2021 to identify all human studies on PER for the treatment of SE of any type and etiology. An additional search was performed on DANS Easy Archive, in which OpenGrey data were stored, from inception until January 10, 2022 and conference proceedings by the International League Against Epilepsy from 2011 onward. The GRADE (Grades of Recommendation, Assessment, Development and Evaluation) approach was used to assess the overall certainty of the body of evidence.. Twenty-one studies (7 case reports, 9 case series, and 5 retrospective cohort studies) were included with a total of 369 cases of SE in 368 patients aged 11 months to 99 years, of which 56.2% were female. Seizures of the majority were refractory (n = 220), super refractory SE (n = 70), or either (n = 81) with prominent motor symptoms (n = 284) and are associated with a structural etiology (n = 218). The number of antiseizure medications and/or anesthetics used prior to PER ranged from 1 to 13. PER was administered in 324 cases and was initiated at a dose of 2-36 mg between 30 min to 59 days from SE onset. SE cessation ranged from 1 h to 4 weeks from PER initiation. A total of 119 cases (36.6%) were considered PER responders. According to the GRADE approach, there is very low certainty of evidence for all outcomes.. The real-world data of PER as a possible therapeutic option in SE of any type are increasing. However, there is very low certainty of evidence for its use and this requires further clinical studies to establish the appropriate timing, dosing, and titration that are efficacious and safe for SE cessation.

Topics: Anticonvulsants; Female; Humans; Infant; Nitriles; Pyridones; Retrospective Studies; Status Epilepticus

The effective dose of perampanel in status epilepticus (SE), refractory SE (RSE), and super-refractory SE (SRSE) in humans is unknown, and the potential of perampanel in treating SE has not been evaluated in a large cohort.. Data of intensive care patients with RSE and SRSE treated with perampanel were retrospectively reviewed and analyzed.. Eighty-one patients received perampanel, including 39 females with median age 64 [17-91] years, perampanel responders (n = 27), and non-responders (n = 54). The initial perampanel dose was positively associated with treatment response in patients with RSE or SRSE (OR = 1.27, 95% CI 1.03-1.57, p = 0.025), while the maximum dose was negatively associated with treatment response (OR = 0.74, 95% CI 0.58-0.96, p = 0.022). Hypoxia caused seizures in six patients; five died in hospital and one had severe disability. A statistically non-significant tendency toward better response was found in patients with unique SE type and cause, particularly in nonconvulsive status epilepticus (NCSE) without coma (NCSE without coma vs. generalized tonic-clonic seizure: OR = 4.14, 95% CI 0.98-17.47, p = 0.053). In the high-dose (≥ 16 mg/day) groups, although distributions of modified Rankin Scale (mRS) scores were similar between perampanel responders and non-responders at discharge, a greater proportion of perampanel responders had less change in mRS scores from baseline than did perampanel non-responders (median mRS: 0 vs 4, p = 0.064). No cardiorespiratory adverse events or laboratory abnormalities were noted with perampanel treatment.. Perampanel is effective and has a satisfactory safety profile in the emergency treatment of established RSE and SRSE.

Topics: Anticonvulsants; Cohort Studies; Female; Humans; Middle Aged; Nitriles; Pyridones; Retrospective Studies; Status Epilepticus

Topics: Anticonvulsants; Clinical Trials as Topic; Epilepsy; Half-Life; Humans; Nitriles; Pyridones; Pyrrolidinones; Receptors, AMPA; Status Epilepticus; Treatment Outcome

Perampanel (PER) is a noncompetitive β-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl)propionic acid (AMPA) receptor antagonist with demonstrated efficacy in animal models of status epilepticus (SE). We performed a systematic review of the literature to assess the efficacy and tolerability of PER in the treatment of refractory and super-refractory SE.. We searched Medline, Embase, and CENTRAL (accessed from inception to April 30, 2018) to identify studies evaluating oral PER as treatment of SE of any type. We also searched the OpenGrey repository and conference proceedings of international congresses by the International League Against Epilepsy and by the American Epilepsy Society from 2012 onwards.. Ten articles were included, with a total of 69 episodes of SE occurring in 68 patients (aged 18 to 91 years). The type and etiology of SE varied remarkably across studies. The number of drugs used prior to PER ranged from 1 to 9. The time from SE onset to PER administration ranged from 9.25 h to 35 days. The initial PER dose ranged from 2 to 32 mg. The proportion of patients achieving clinical SE cessation varied from 17% to 100%. The time from PER administration to SE cessation ranged from 1 h to 4 weeks.. The currently available evidence supporting the use of PER in SE is weak and hampered by several confounding factors. Further studies should be performed in more clinically homogeneous and larger cohorts to evaluate the efficacy and safety of PER administered in earlier stages of SE, at higher dosages, and at intervals shorter than 24 h.

Topics: Animals; Anticonvulsants; Humans; Nitriles; Pyridones; Receptors, AMPA; Status Epilepticus; Treatment Outcome

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.

Topics: Anticonvulsants; Brain Neoplasms; Epilepsy; Epilepsy, Generalized; Epilepsy, Temporal Lobe; Humans; Nitriles; Pyridones; Receptors, AMPA; Status Epilepticus

Perampanel is the latest approved antiepileptic drug in focal and generalized epilepsies and has a distinct and selective mode of action on AMPA-receptors. Several thousand patients have received perampanel within randomized placebo-controlled trials, open-label extension trials and post-marketing observational studies. Significant median partial-onset seizure reduction rates of 23% for 4 mg/day, 26-31% for 8 mg/day and 18-35% for 12 mg/day were reported. Likewise 50 percent responder rates were 29% for 4 mg/day, 33-38% for 8 mg/day and 34-36% for 12 mg/day. Primary generalized tonic-clonic seizures were reduced by 76.5% (8 mg) vs 38.4% (placebo) in a recent controlled trial. Overall, perampanel is well tolerated and the main adverse events are dizziness, somnolence and fatigue. There are also anecdotal reports on use in progressive myoclonic epilepsies and status epilepticus. Perampanel will likely remain an important, possibly broad-spectrum AED with a significant market share, especially in patients with drug-refractory epilepsies.

Topics: Animals; Anticonvulsants; Epilepsies, Partial; Epilepsy, Generalized; Humans; Nitriles; Pyridones; Receptors, AMPA; Status Epilepticus

Status epilepticus in poststroke epilepsy is a challenging condition because of multiple vascular comorbidities and the advanced age of patients. Data on third-generation antiseizure medication (ASM) in this condition are limited. The aim of this study was to evaluate the efficacy of third-generation ASMs in the second- or third-line therapy of benzodiazepine-refractory status epilepticus in poststroke epilepsy following acute ischemic stroke.. Data on the effectiveness of third-generation ASMs in patients with status epilepticus in poststroke epilepsy were gathered from two German Stroke Registries and the Mainz Epilepsy Registry. We included only cases with epilepsy remote to the ischemic event. No patients with acute symptomatic seizures were included. The following third-generation ASMs were included: brivaracetam, lacosamide, eslicarbazepine, perampanel, topiramate, and zonisamide. The assessment of effectiveness was based on seizure freedom within 48 h since the start of therapy with the respective ASM. Seizure freedom was evaluated both clinically (clinical evaluation at least three times per day) and by daily electroencephalogram records.. Of the 138 patients aged 70.8 ± 8.1 years with benzodiazepine-refractory status epilepticus in ischemic poststroke epilepsy, 33 (23.9%) were treated with lacosamide, 24 (17.4%) with brivaracetam, 23 (16.7%) with eslicarbazepine, 21 (15.2%) with perampanel, 20 (14.5%) with topiramate, and 17 (12.3%) with zonisamide. Seizure freedom within 48 h was achieved in 66.7% of patients with lacosamide, 65.2% with eslicarbazepine, 38.1% with perampanel, 37.5% with brivaracetam, 35.0% with topiramate, and 35.3% with zonisamide (p < 0.05 for comparison of lacosamide or eslicarbazepine to other ASMs).. Based on these data, lacosamide and eslicarbazepine might be more favorable in the treatment of refractory status epilepticus in poststroke epilepsy, when administered as second- or third-line ASMs before anesthesia. Because of the fact that these ASMs share the same mechanism of action (slow inactivation of sodium channels), our findings could motivate further research on the role that this pharmaceutical mechanism of action has in the treatment of poststroke epilepsy.. This study was registered at ClinicalTrials.gov (NCT05267405).

Topics: Aged; Anticonvulsants; Benzodiazepines; Epilepsy; Humans; Ischemic Stroke; Lacosamide; Middle Aged; Retrospective Studies; Seizures; Status Epilepticus; Topiramate; Zonisamide

Status epilepticus (SE) continues to be a challenging neurological emergency with high morbidity and mortality. During treatment, different regimens are practiced encompassing all known seizure termination mechanisms. To our knowledge, this is the first case series report describing EEG patterns and clinical outcomes in patients treated with ketamine and perampanel (PER) concomitantly.. To assess clinical and electrographic outcomes in patients receiving dual antiglutamatergic therapy in SE.. Twenty-one out of twenty five patients were treated with ketamine, and four patients with ketamine were associated with PER. In the ketamine plus PER group, three out of four patients had convulsive SE, and one had non-convulsive status epilepticus (NCSE), whereas eight patients in the ketamine group had NCSE. The incidence of beta pattern appearance on EEG after starting patients on ketamine and PER was achieved in all four patients (100%) compared to (61.9%) in the other group. A burst suppression pattern was recorded in 75% of patients treated with ketamine and PER, in comparison to 28.5% of patients in patients treated with a different regimen. The time to resolution of SE was significantly shorter in the ketamine group (median 24 (24-64) h vs. 6 (05-144) h p > 0.05). Moreover, the average number of days on IV anesthetic was slightly lower in a patient treated with PER concomitantly. In terms of morbidity, the average increase in mRS was also lower in the ketamine and PER group, although it was not statistically significant.. Dual anti-glutamatergic therapy could provide a favorable approach to treating SE, which yet needs to be further investigated through larger randomized control studies.

Topics: Electroencephalography; Humans; Ketamine; Pyridones; Status Epilepticus

Status epilepticus (SE) and acute repetitive seizure (ARS) are emergency conditions associated with significant morbidity and mortality in children. Anti-seizure medications (ASMs) need to terminate seizures to prevent brain damage and death. Common challenges that delay the management of SE and ARS in children at Phramongkutklao hospital are difficulty in accessing intravenous route for drug administration and inadequate number of intensive care units (which will be required in case of the use of adverse events to anesthetic ASMs). Oral, non-sedating ASMs could be a potential option to terminate seizures effectively in SE and ARS in children and further studies in this aspect are needed. We performed a prospective, descriptive study in children with SE or ARS < 18 years of age who had contraindication to or their seizures were refractory to the second-line ASMs after benzodiazepine and received oral perampanel. Demographic data, efficacy, and adverse effects of treatment were recorded. Fifteen patients with SE (13.3%) and acute repetitive seizure (86.6%) were enrolled. All patients received an oral perampanel loading dose and the maintenance dose depended on their body weight. The average loading and maintenance dose were 0.24 mg/kg/dose and 0.12 mg/kg/day, respectively. At 48 h after administration of loading dose of perampanel, eight of fifteen patients (53.3%) became seizure free, one patient had seizure reduction of >75% from baseline, and three patients had seizure reduction of 25-50% from baseline. No serious side effects were observed. These results indicate that oral perampanel may be potential treatment option for SE and ARS in children.

Topics: Anticonvulsants; Child; Humans; Nitriles; Prospective Studies; Pyridones; Seizures; Status Epilepticus; Tertiary Care Centers; Thailand; Treatment Outcome

Topics: Anticonvulsants; Humans; Ketamine; Nitriles; Pyridones; Status Epilepticus

Combinations of midazolam, allopregnanolone, and perampanel were assessed for antiseizure activity in a rat diisopropylfluorophosphate (DFP) status epilepticus model. Animals receiving DFP followed by atropine and pralidoxime exhibited continuous high-amplitude rhythmical electroencephalography (EEG) spike activity and behavioral seizures for more than 5 hours. Treatments were administered intramuscularly 40 min after DFP. Seizures persisted following midazolam (1.8 mg/kg). The combination of midazolam with either allopregnanolone (6 mg/kg) or perampanel (2 mg/kg) terminated EEG and behavioral status epilepticus, but the onset of the perampanel effect was slow. The combination of midazolam, allopregnanolone, and perampanel caused rapid and complete suppression of EEG and behavioral seizures. In the absence of DFP, animals treated with the three-drug combination were sedated but not anesthetized. Animals that received midazolam alone exhibited spontaneous recurrent EEG seizures, whereas those that received the three-drug combination did not, demonstrating antiepileptogenic activity. All combination treatments reduced neurodegeneration as assessed with Fluoro-Jade C staining to a greater extent than midazolam alone, and most reduced astrogliosis as assessed by GFAP immunoreactivity but had mixed effects on markers of microglial activation. We conclude that allopregnanolone, a positive modulator of the GABA

Topics: Animals; Behavior, Animal; Drug Therapy, Combination; Electroencephalography; Isoflurophate; Male; Midazolam; Nitriles; Pregnanolone; Pyridones; Rats; Rats, Sprague-Dawley; Status Epilepticus

The outcomes of administration of Perampanel (PER) which is a β-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl)propionic acid (AMPA) receptor antagonist for the treatment of refractory status epilepticus (RSE) and Super-refractory (SRSE) were previously reported in small cohort studies and case reports. We report efficacy and side effect results of an observational cohort of 75 patients treated with PER for RSE and SRSE.. This was a single-center, retrospective, observational study of patients with RSE admitted to the neurocritical care unit between April 2017 and September 2019 who received treatment with PER. The primary outcome was the occurrence of a definite response to PER, which was defined as clear resolution of the ictal pattern and/or seizures within 72 h of delivery of PER which was the last administered antiseizure medication (ASM). Secondary outcomes included the percentage of patients other response types (partial responder or non-responder), as well as the rate of adverse effects.. A total 75 patients were included in our analysis. PER was initiated as the median sixth ASM at a median initial dose of 12 mg. For the primary outcome, 31 (41.3%; 95% confidence interval 31.0%-53.0%) patients were classified as a definite responder. Seven patients (9.3%) experienced an adverse effect that was attributed to PER, with the most common being sedation in four patients.. In our retrospective cohort of RSE, we observed a definite response rate of 41.3% within 72 h of PER initiation. PER was well tolerated with few documented adverse effects. Further prospective studies are needed to confirm the role of PER in treating patients with RSE.

Topics: Anticonvulsants; Humans; Nitriles; Prospective Studies; Pyridones; Retrospective Studies; Status Epilepticus; Treatment Outcome

Pilocarpine-induced status epilepticus (SE), which results in the development of spontaneous recurrent seizures (SRSs) activates glutamatergic receptors that contribute to seizure sustenance and neuronal cell death. In the current study, we evaluate whether the exposure to perampanel, an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor blocker, or amantadine, a N-methyl-D-aspartic acid (NMDA) receptor blocker would reduce the SE-induced long-term consequences. SE was induced in adult male Sprague Dawley rats with pilocarpine. Perampanel or amantadine was injected 10 or 60 min after SE onset. The efficacy of either, in overcoming pilocarpine-induced SE was assessed using electroencephalogram (EEG) recordings. In addition, alterations in cognitive function, development of spontaneous recurrent seizures (SRSs), and hippocampal damage that are generally encountered after SE were also assessed at 72 h and 5 weeks after the induction of SE. Our results indicate that both early and late treatment with perampanel but not amantadine significantly reduced seizure activity. Furthermore, perampanel but not amantadine, reversed the memory deficits in Y-maze and novel object recognition (NOR) tests and retarded the appearance of SRSs. Moreover, perampanel treatment led to reduced SE-induced caspase-3 activation in the hippocampal lysates. Taken together, the data obtained from the study reveals that blocking AMPA receptors by perampanel can modify SE-induced long-term consequences. Our results may provide a proof of principle for the potential therapeutic application of perampanel in clinical use for status epilepticus in future.

Topics: Amantadine; Animals; Astrocytes; Behavior, Animal; Caspase 3; Cell Survival; Cognition Disorders; Disease Models, Animal; Enzyme Activation; Male; Neurons; Nitriles; Pilocarpine; Protein Subunits; Pyridones; Rats, Sprague-Dawley; Receptors, AMPA; Seizures; Status Epilepticus

Novel treatments are needed to control treatment-resistant status epilepticus (SE). We report a summary of clinical cases where perampanel was used in established SE, refractory SE (RSE), or super-refractory SE (SRSE).. Medical records were retrospectively reviewed for perampanel administration in SE at five European hospitals between 2011 and 2015.. Of 1319 patients identified as experiencing SE, 52 (3.9%) received perampanel. Median latency from SE onset to perampanel initiation was 10 days. Patients with SE had previously failed benzodiazepines (when received) and a median of five other antiepileptic drugs (AEDs). Median initial perampanel dose was 6 mg/d, up-titrated to a median maximum dose of 10 mg/d. Perampanel was the last drug added in 32/52 (61.5%) patients, with response attributed to perampanel in 19/52 (36.5%) patients. A greater proportion of perampanel non-responders had SRSE (51.5%; 17/33) vs perampanel responders (31.6%; 6/19), and had failed a higher mean number of AEDs before initiating perampanel (5.9 vs 5.1, respectively). Most commonly reported adverse effects during perampanel treatment were dizziness (n = 1 [1.9%]) and somnolence (n = 1 [1.9%]). No serious adverse effects were documented, and none led to discontinuation of perampanel.. Perampanel was administered to patients with established SE, RSE, or SRSE at greater initial doses than those administered in clinical practice to patients with epilepsy. The SE cases reported here represent a refractory and heterogeneous population, and rate of seizure cessation attributed to perampanel treatment (36.5%) represents a notable response. These data should be confirmed in a larger patient population.

Topics: Adult; Anticonvulsants; Austria; Female; Finland; Germany; Humans; Male; Middle Aged; Nitriles; Pyridones; Retrospective Studies; Seizures; Spain; Status Epilepticus; Treatment Outcome

Perampanel is a novel anti-epileptic drug (AED) which acts as a non-competitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist to reduce glutamate-mediated postsynaptic excitation. Previous animal studies and a few case reports/series have suggested that it may be effective to treat refractory status epilepticus (RSE).. We retrospectively reviewed 67 consecutive patients with RSE, of whom 22 received perampanel. The clinical features, epidemiology-based mortality score in status epilepticus, status epilepticus severity score, seizure control, functional outcome, RSE etiology, and electroencephalogram findings were collected. Responder to perampanel was defined as seizure resolution within 4 days of therapy with perampanel being the last AED used plus no recurrence during hospitalization.. Eight of the 22 (36.4%) RSE patients fulfilled the definition of responder to perampanel. An additional 1 patient responded to perampanel after 4 days of treatment. In total, perampanel was the last AED in 9 (40.1%) patients. Among the 8 responders to perampanel, 5 had convulsive SE, 1 had non-convulsive SE, and 2 had focal motor SE. The responders accounted for both of the patients with focal motor SE (100%), 5 (33.3%) of the 15 patients with convulsive SE, and 1 (20%) of the 5 patients with non-convulsive SE. The ictal and inter-ictal activities also decreased after perampanel therapy, and three patients (13.6%) had preferable outcomes at last follow-up.. Perampanel may be an effective add-on treatment for RSE even in patients who failed multiple AEDs. Our study suggests that perampanel may be more effective for focal motor SE and convulsive SE than non-convulsive SE. As most previous studies have focused on non-convulsive SE, further studies are warranted to clarify the effectiveness of perampanel for different subtypes of SE.

Topics: Adult; Aged; Aged, 80 and over; Anticonvulsants; Critical Care; Electroencephalography; Female; Hospitalization; Humans; Male; Middle Aged; Nitriles; Pyridones; Retrospective Studies; Status Epilepticus; Treatment Outcome

Topics: Humans; Intensive Care Units; Nitriles; Pyridones; Status Epilepticus

In refractory status epilepticus (SE), γ-aminobutyric acidergic drugs become less effective and glutamate plays a major role in seizure perpetuation. Data on the efficacy of perampanel (PER) in treatment of refractory SE in humans are limited. Here, we present a single-center case series of patients with refractory SE who received PER orally in an intensive care unit. We retrospectively analyzed treatment response, outcome, and adverse effects of all patients with refractory SE in our Neurological Intensive Care Unit who received add-on PER between September 2012 and February 2018. Thirty patients with refractory SE (median = 72 years, range = 18-91, 77% women) were included. In 14 patients (47%), a high-dose approach was used, with a median initial dose of 24 mg (range = 16-32). In five patients (17%), SE could be terminated after PER administration (median dose = 6 mg, range = 6-20 mg, 2/5 patients in high-dose group). Clinical response was observed after a median of 24 hours (range = 8-48 hours), whereas electroencephalogram resolved after a median of 60 hours (range = 12-72 hours). Time to treatment response tended to be shorter in patients receiving high-dose PER (median clinical response = 16 hours vs 18 hours; electroencephalographic response = 24 hours vs 72 hours), but groups were too small for statistical analysis. Continuous cardiorespiratory monitoring showed no changes in cardiorespiratory function after "standard" and "high-dose" treatment. Elevated liver enzymes without clinical symptoms were observed after a median of 6 days in seven of 30 patients (23%; 57% high dose vs 43% standard dose), of whom six also received treatment with phenytoin (PHT). Outcome was unfavorable (death, persistent vegetative state) in 13 patients (43%; 39% high dose vs 61% standard dose), and good recovery (no significant disability, moderate disability) was achieved in nine patients (56% high dose vs 44% standard dose). Oral PER in loading doses up to 32 mg were well tolerated but could terminate SE only in a few patients (5/30; 17%). Long duration of SE, route of administration, and severe underlying brain dysfunction might be responsible for the modest result. An intravenous formulation is highly desired to explore the full clinical utility in the treatment of refractory SE.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anticonvulsants; Austria; Electroencephalography; Female; Humans; Intensive Care Units; Male; Middle Aged; Nitriles; Pyridones; Retrospective Studies; Status Epilepticus; Treatment Outcome; Young Adult

Refractory nonconvulsive status epilepticus (NCSE) occurs in 10%-30% of patients following resuscitation after cardiac arrest. Both the optimal treatment and prognosis of postanoxic status epilepticus remain uncertain. We analyzed acute electroencephalographic changes, neurological outcome at 3 months, and adverse effects in consecutive postanoxic patients with super-refractory NCSE treated with add-on oral loading of perampanel. Eight postanoxic patients with super-refractory NCSE were treated with perampanel (dose range = 6-12 mg). All patients had continuous electroencephalographic monitoring showing definite generalized NCSE and favorable multimodal prognostic indicators (presence of brainstem reflexes, presence of bilateral N20 responses, absence of periodic discharges/generalized epileptic periodic discharges). In six patients (75%), status epilepticus resolved within 72 hours after administration of perampanel, without changing the comedication. Neurological outcomes at 3 months were return to normal or minimal disability in four patients (50%). A mild cholestatic liver injury, which required no specific treatment, was observed in five patients (62.5%). Perampanel 6-12 mg oral loading appeared to be an effective option in selected patients with postanoxic super-refractory NCSE with good prognostic indicators. In this patient population, our safety data indicate a risk of cholestasis.

Topics: Administration, Oral; Adult; Aged; Anticonvulsants; Dose-Response Relationship, Drug; Electroencephalography; Female; Heart Arrest; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Nitriles; Pilot Projects; Pyridones; Retrospective Studies; Status Epilepticus; Treatment Outcome

Status epilepticus (SE) causes irreversible neurodegeneration if not terminated quickly. Perampanel (PER), a potent AMPA receptor antagonist, has previously been shown to terminate seizures in the lithium-pilocarpine SE model. In the present study, we assessed whether PER would also prevent neuronal damage in this model.. SE was induced in rats using lithium chloride and pilocarpine. Initiation of SE was defined as continuous seizures that exhibited as rearing accompanied by bilateral forelimb clonus (Racine score 4). Either PER (0.6, 2, or 6mg/kg) or diazepam (DZP, 10mg/kg) was administered intravenously 30min after SE initiation. Histopathological samples from treated and seizure-naive rats were taken one week after treatment and then stained with an anti-neuronal nuclei (NeuN) antibody. The sections were analyzed by using a pixel-counting algorithm to quantify the amount of staining in the CA1 subregion of the hippocampus, piriform cortex (Pir), and mediodorsal thalamic nucleus (MD).. DZP administration did not suppress seizures or the degeneration of neurons in the examined areas. Seizures were terminated in 100% of rats treated with 6mg/kg PER (n=8) and in 47% (7/15) of rats treated with 2mg/kg PER, and neurons in the analyzed areas of these animals were preserved to the level seen in naive rats. In the eight animals in which 2mg/kg PER did not terminate the seizures, neuronal loss was partially attenuated in CA1 and Pir, and neurons were fully preserved in MD. Treatment with 0.6mg/kg PER did not terminate the seizures or significantly preserve neurons. The anti-seizure effect of PER correlated well with the degree of neuroprotection in each analyzed area.. PER exhibited a strong neuroprotective effect in a drug-refractory SE model, and this effect was correlated with its attenuation of seizure.

Topics: Animals; Anticonvulsants; Antigens, Nuclear; Brain; Cell Death; Diazepam; Dose-Response Relationship, Drug; Immunohistochemistry; Lithium Chloride; Male; Nerve Tissue Proteins; Neurodegenerative Diseases; Neurons; Neuroprotective Agents; Nitriles; Pilocarpine; Pyridones; Rats, Sprague-Dawley; Status Epilepticus

The purpose of this study was to evaluate changes in health care resource utilization following the initiation of perampanel for the treatment of epilepsy in the United States.. Health care claims from Symphony Health's Integrated Dataverse database between December 2012 and November 2015 were analyzed. Patients newly initiated on perampanel, having ≥1 epilepsy (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 345.xx, ICD-10-CM code G40.xxx) or nonfebrile convulsion (ICD-9-CM code 780.39, ICD-10-CM code R56.9) diagnosis, and having ≥6 months of baseline and observation periods were included. Patients <12 years old at perampanel initiation were excluded.. Of the 2,508 perampanel patients included in the study, the mean [median] (±standard deviation [SD]) age was 35.8 [34] (±16.0) years and 56.2% were female. The mean [median] (±SD) observation duration was 459.8 [462] (±146.3) days in the postperampanel period. The postperampanel period was associated with significantly lower rates of all health care resource utilization outcomes than the pre-period. For the post- versus pre-period, perampanel users had 42.3 versus 53.8 overall hospitalizations per 100 person-years (rate ratio [RR] = 0.80, p < 0.001) and 1,240.2 versus 1,343.8 outpatient visits per 100 person-years (RR = 0.91, p < 0.001). Epilepsy-related hospitalizations and outpatient visits were 25.2 versus 33.6 per 100 person-years (RR = 0.76, p < 0.001) and 327.0 versus 389.0 per 100 person-years (RR = 0.84, p < 0.001), respectively. Additionally, a significantly lower rate of status epilepticus in the post-period (1.8 events per 100 person-years) was observed compared to the pre-period (4.4 events per 100 person-years; RR = 0.43, p < 0.001). The monthly time trend of hospitalizations showed an increasing trend leading up to the initiation of perampanel, after which the hospitalizations decreased steadily.. Use of perampanel for the treatment of epilepsy was associated with significant reduction in all-cause and epilepsy-related health care resource utilization, including hospitalizations, especially for status epilepticus, and outpatient visits.

Topics: Adolescent; Adult; Aged; Ambulatory Care; Anticonvulsants; Child; Epilepsy; Female; Health Services; Hospitalization; Humans; Male; Middle Aged; Nitriles; Pyridones; Status Epilepticus; United States; Young Adult

We provide some evidence concerning the efficacy of perampanel (PER) in refractory status epilepticus (SE). We retroactively identified patients with SE treated in our department by searching for the term "status epilepticus" in the electronic archive of medical records. We present and analyze in this paper the subset of data of the patients treated with PER. We analyzed ten episodes of SE in nine patients. At the first administration, PER was given in a dosage of 6mg to most of our patients (7 of 10). On average, PER was administered as the 6th antiepileptic drug (AED) (range: 2-10). Depending on the criterion for efficacy, PER appears effective for the termination of SE in 2 to 6 (of 10) episodes. Unfortunately, safety data for the administration of PER with loading doses needed for the treatment of SE are lacking. Because of this, PER should be used very carefully in refractory SE and only after first-line treatment options have failed.

Topics: Aged; Aged, 80 and over; Anticonvulsants; Electronic Health Records; Female; Humans; Male; Middle Aged; Nitriles; Pyridones; Retrospective Studies; Status Epilepticus; Treatment Outcome

The AMPA receptor subtype of glutamate receptors, which mediates fast synaptic excitation, is of primary importance in initiating epileptiform discharges, so that AMPA receptor antagonists exert anti-seizure activity in diverse animal models of partial and generalized seizures. Recently, the first AMPA receptor antagonist, perampanel, was approved for use as adjunctive therapy for the treatment of resistant partial seizures in patients. Interestingly, the competitive AMPA receptor antagonist NBQX has recently been reported to prevent development of spontaneous recurrent seizures (SRS) in a neonatal seizure model in rats, indicating the AMPA antagonists may exert also antiepileptogenic effects. This prompted us to evaluate competitive (NBQX) and noncompetitive (perampanel) AMPA receptor antagonists in an adult mouse model of mesial temporal lobe epilepsy. In this model, SRS develop after status epilepticus (SE) induced by intrahippocampal injection of kainate. Focal electrographic seizures in this model are resistant to several major antiepileptic drugs. In line with previous studies, phenytoin was not capable of blocking such seizures in the present experiments, while they were markedly suppressed by NBQX and perampanel. However, perampanel was less tolerable than NBQX in epileptic mice, so that only NBQX was subsequently tested for antiepileptogenic potential. When mice were treated over three days after kainate-induced SE with NBQX (20 mg/kg t.i.d.), no effect on development or frequency of seizures was found in comparison to vehicle controls. These results suggest that AMPA receptor antagonists, while being effective in suppressing resistant focal seizures, are not exerting antiepileptogenic effects in an adult mouse model of partial epilepsy.

Topics: Animals; Anticonvulsants; Chronic Disease; Disease Models, Animal; Electroencephalography; Epilepsy, Temporal Lobe; Female; Hippocampus; Kainic Acid; Mice; Nitriles; Phenytoin; Pyridones; Quinoxalines; Receptors, AMPA; Seizures; Status Epilepticus

In refractory status epilepticus (SE), because of subcellular maladaptive changes, GABAergic drugs are no longer effective, and the excitatory neurotransmitter glutamate (Glu) plays a major role in seizure perpetuation. Perampanel (PER, licensed since 09/2012) is the first orally active noncompetitive AMPA receptor antagonist for adjunctive treatment of refractory focal epilepsy.. We analyzed treatment response, seizure outcome, and adverse effects of add-on treatment with perampanel in patients with refractory status epilepticus in the Neurological Intensive Care Unit (NICU), Salzburg, Austria between 09/2012 and 11/2014 by retrospective chart review.. Twelve patients (75% women) with refractory status epilepticus were treated with PER administered per nasogastric tube between 09/2012 and 11/2014. Median age was 75 years [range: 60-91]. The most frequent SE type was nonconvulsive SE (NCSE) with (5/12, 42%) and without coma (6/12, 50%). In seven patients (58%), SE arose de novo, with an acute symptomatic cause in five patients (42%). Cerebrovascular diseases (4/12, 33%) and cerebral tumors (4/12, 33%) were the most common etiologies. Perampanel was given after a median number of four antiepileptic drugs [range: 2-7] and a median time of 1.5 days [range: 0.8-18.3]. In one patient (8%), clinical improvement was observed within 24h and EEG improvement within 60 h after administration of PER, while in another patient (8%), clinical and EEG improvement was observed more than 48 h after administration. Median initial dose was 4 mg [range: 2-12; SD: 4.11], titrated up to a median of 12 mg [range: 4-12] in steps of 2 to 4 mg per day. No adverse effects were reported regarding cardiorespiratory changes or laboratory parameters. Outcomes after SE were moderate disability in five patients (42%), death in three patients (25%), and persistent vegetative state in two patients (17%).. Though glutamate plays a major role in seizure perpetuation, the noncompetitive AMPA receptor antagonist PER could only ameliorate seizure activity in a few patients with refractory SE. The long duration of SE before the administration of PER via nasogastric tube, as well as relatively low doses of PER, might be responsible for the modest result. Perampanel was well tolerated, and no adverse events were reported. This article is part of a Special Issue entitled Status Epilepticus.

Topics: Aged; Aged, 80 and over; Anticonvulsants; Coma; Critical Care; Drug Resistant Epilepsy; Electroencephalography; Excitatory Amino Acid Antagonists; Female; Glasgow Outcome Scale; Humans; Intensive Care Units; Length of Stay; Male; Middle Aged; Nitriles; Pyridones; Receptors, AMPA; Retrospective Studies; Status Epilepticus; Treatment Outcome

Topics: Aged, 80 and over; Animals; Anticonvulsants; Electroencephalography; Epilepsy, Tonic-Clonic; Female; Humans; Nitriles; Pyridones; Status Epilepticus