Impact of Perampanel for First-Episode Seizures versus Usual Care on Clinical Outcome and Safety Profile Aspects of the Thai Experience

Abstract

Background and purpose: Epilepsy increases poor outcomes in patients with post-traumatic brain injury and brain tumor-related epilepsy, for whom early seizure control is essential. Perampanel (PER) was a known third-generation antiepileptic drug for treatment all types of seizures. The objective of the study is to compare clinical outcomes and safety of PER administration as monotherapy.

Methods: A prospective study of all 84 patients assigned to PER monotherapy (PER group, n=36) and other first-line antiepileptic drugs (n=48). Clinical outcomes parameters were measured by the prevalence of patients with a diminish in seizure frequency at 50% in 28 days. From November 1, 2020 to April 30, 2024, comparing the PER group with usual care. Clinical outcomes included adherence rate and seizure-free proportion at 28 days and 6 months. Adverse drug reactions were recorded in both groups.

Results: There was no difference in demographic data and incidence of adverse drug reactions between two groups. Median PER dosage was 4 mg (range, 2-12 mg). Compared to other antiepileptic drugs, the PER group had a prevalence of 50% responder rate at 28 days and 6 months significantly were 75%, 81%, 65%, and 51% respectively. Common adverse drug reactions were somnolence and dizziness.

Conclusions: PER administration as monotherapy demonstrated good efficacy and less adverse drug reactions. Low dosages helped to decrease adverse drug reactions and improved retention rate.

Keywords: Adverse drug reaction; Antiepileptic drugs; Epilepsy; Seizures; Traumatic brain injury.

Figure 1

Illustration of the number of patients evaluated at each visit who have been treated with perampanel (PER) monotherapy and phenytoin monotherapy at some point during the first 6 month. ADRs, adverse drug reactions; OP, observation point.

Figure 2

Comparison between retention rates on perampanel monotherapy and phenytoin monotherapy evaluated at each visit at some point during the first 28 days and 6 months. OP, observation point; PER, perampanel.

Figure 3

Seizure-response status and seizure-free status at OP 28 days and 6 months on perampanel monotherapy. OP, observation point.

Figure 4

Seizure-response status and seizure-free status at different age at OP 28 days and 6 months on perampanel monotherapy. OP, observation point.

Figure 5

Seizure-response status and seizure-free status at titration speed at OP 28 days and 6 months on perampanel monotherapy. OP, observation point.

Figure 6

Retention rate at different age at OP 28 days and 6 months on perampanel monotherapy. OP, observation point.

Figure 7

Retention rate status at titration speed at OP 28 days and 6 months on perampanel monotherapy. OP, observation point.

Figure 8

Seizure-response status and seizure-free status at initial dosage at OP 28 days and 6 months on perampanel monotherapy. OP, observation point.

Figure 9

Retention rate status at initial dosage at OP 28 days and 6 months on perampanel monotherapy. OP, observation point.

Figure 10

Comparison statistics between PER and phenytoin in median percentage change in seizure frequency per 28 days and 6 months. OP, observation point; PER, perampanel. *p-value analyzed using Chi-square test.

Figure 11

Comparison statistics between PER and phenytoin in responder rates (percentage of patients achieving a 50% reduction in seizure frequency per 28 days and 6 months). OP, observation point; PER, perampanel. *p-value analyzed using Chi-square test.