Effectiveness and tolerability of perampanel in children and adolescents with refractory epilepsies-An Italian observational multicenter study

Effectiveness and tolerability of Perampanel in children, adolescents and young adults with refractory epilepsy: A UK national multicentre study

PURPOSE

Perampanel is one of the latest antiepileptic drugs (AEDs) approved for the treatment of focal and generalised epilepsy in individuals with epilepsy aged 12 years and older. There is sparse data on the use of Perampanel in children under 12. We conducted a study amongst paediatric neurologists in the United Kingdom to investigate its effectiveness and tolerability as an adjunctive therapy in children of all ages with refractory epilepsy.

METHODS

Data was collected via an online questionnaire sent to paediatric neurologists in the UK. Data gathered, prospective in 62 (64.5%) and retrospective in 34 (35.5%) patients, included changes in seizure frequency from baseline and unwanted effects at 3, 6 and 12 months follow-up. Only patients with a minimum follow-up of six months were included.

RESULTS

Ninety six patients (48 females) with refractory epilepsy from 11 of 29 tertiary centres were included. Median [IQR] (range) age was 14 years 11 months [12 years, 16 years 6 months] (11 months-24 years 5 months). Seventy three (76%) had focal epilepsy, sixteen (17%) generalised, and seven (7%) patients both generalised and focal epilepsy. The responder rate, ≥50% seizure reduction from baseline, was 19% for all seizure types at both 6 and 12 months, 19% and 24% for focal seizures, and 25% and 7% for generalised seizures at these time points respectively. The retention rate was 42% at 12 months. Treatment was discontinued due to unwanted effects in 29 (36.7%) of the 79 patients with follow-up data available up to 12 months: 30% due to challenging behaviour, 14% dizziness, and 7.6% somnolence.

CONCLUSION

Perampanel was fairly effective in a heterogeneous group of 96 children and adolescents with very refractory epilepsy. The rate of adverse events leading to discontinuation was considerable in this group.

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.

Clinical Experience With Perampanel for Refractory Pediatric Epilepsy in One Canadian Center

Perampanel (PER) is a new antiseizure medication that inhibits the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) class of glutamate receptors. It is important for physicians to be aware of the efficacy and tolerability of new drugs in the postmarketing phase. We performed a retrospective review of our experience with perampanel at BC Children's Hospital. Twenty-four pediatric patients prescribed perampanel from 2014 to 2016 were identified. Fifteen (63%) discontinued perampanel, and 10 (42%) had greater than 50% reduction in seizures. Twelve (50%) had behavioral and 8 (33%) had nonbehavioral adverse events. One-third experienced serious adverse events. One patient experienced oculogyric crisis, which is not previously reported with perampanel. Adverse events were not dose related and were reversible. Possible risk factors for behavioral adverse events include a history of behavioral problems with other antiseizure medications and preexisting behavioral comorbidities. It is important to counsel patients about the potential for serious adverse events, particularly behavioral, when prescribing perampanel.

Current role of perampanel in pediatric epilepsy

Perampanel is among the latest AEDs approved, indicated for the treatment of partial-onset seizures with or without secondary generalization, and for primary generalized tonic-clonic seizures, in patients aged 12 years and older. This paper summarizes the clinical recommendations on the current role of perampanel in the treatment of pediatric epilepsies and future directions for research. The optimal dosage should be comprised between 4 and 12 mg/day, with 8 mg/day being the most common dosage used. The rate and severity of adverse events, including psychiatric symptoms, can be decreased by starting at low doses, and titrating slowly. Overall, perampanel presents an acceptable risk/benefit ratio, but special caution should be made to the risk of seizure aggravation and behavioral problems. The favorable cognitive profile, the ease of use of the titration scheme and the once-daily formulation offer advantage over other AEDs and make this drug particularly suitable for adolescent population. Perampanel is a welcome addition to the armamentarium of the existing AEDs, as it represents a new approach in the management of epilepsy, with a novel mechanism of action and a potential to have a considerable impact on the treatment of adolescents with epilepsy.

Update on pharmacotherapy of myoclonic seizures

INTRODUCTION

Myoclonic seizures are brief, involuntary muscular jerks arising from the central nervous system that can occur in different epilepsy syndromes, including idiopathic generalized epilepsies or the most severe group of epileptic encephalopathies. Valproate is commonly the first choice alone or in combination with some benzodiazepines or levetiracetam. However, more treatment options exist today as there is emerging evidence to support the efficacy of some newer antiepileptic drugs. In addition, of major importance remains avoidance of medications (e.g., carbamazepine, phenytoin) that may aggravate myoclonic seizures. This is an updated review on the available therapeutic options for treatment of myoclonic seizures. Areas covered: Key efficacy, tolerability and efficacy data are showed for different antiepileptic drugs with antimyoclonic effect, alone and/or in combination. Expert opinion: Pharmacological treatment of myoclonic seizures is based on clinical experience with little evidence from randomized clinical trials. Valproate, levetiracetam, and some benzodiazepines, are widely used. There is still insufficient evidence for the use of other antiseizure drugs, such as topiramate or zonisamide as monotherapy. Better understanding of pathophysiologic mechanisms of myoclonic epilepsies could yield great improvement in the treatment and quality of life of patients.