Perampanel for Treatment of People with a Range of Epilepsy Aetiologies in Clinical Practice: Evidence from the PERMIT Extension Study

INTRODUCTION

It is important to assess the effectiveness of an antiseizure medication in treating different epilepsy aetiologies to optimise individualised therapeutic approaches. Data from the PERaMpanel pooled analysIs of effecTiveness and tolerability (PERMIT) Extension study were used to assess the effectiveness and safety/tolerability of perampanel (PER) when used to treat individuals with a range of epilepsy aetiologies in clinical practice.

METHODS

A post hoc analysis was conducted of PERMIT Extension data from individuals with a known aetiology. Retention was assessed after 3, 6 and 12 months. Effectiveness was assessed after 3, 6 and 12 months and at the last visit (last observation carried forward). Effectiveness assessments included responder rate (≥ 50% seizure frequency reduction) and seizure freedom rate (no seizures since at least the prior visit). Safety/tolerability was assessed by evaluating adverse events (AEs) and AEs leading to discontinuation.

RESULTS

PERMIT Extension included 1945 individuals with structural aetiology, 1012 with genetic aetiology, 93 with an infectious aetiology, and 26 with an immune aetiology. Retention rates at 12 months were 61.1% (structural), 65.9% (genetic), 56.8% (infectious) and 56.5% (immune). At the last visit, responder rates (total seizures) were 43.3% (structural), 68.3% (genetic), 37.0% (infectious) and 20.0% (immune), and corresponding seizure freedom rates were 15.8%, 46.5%, 11.1% and 5.0%, respectively. AE incidence rates were 58.0% (structural), 46.5% (genetic), 51.1% (infectious) and 65.0% (immune), and corresponding rates of discontinuation due to AEs over 12 months were 18.9%, 16.4%, 18.5% and 21.7%, respectively. The types of AEs reported were generally consistent across aetiology subgroups, with no idiosyncratic AEs emerging.

CONCLUSION

Although PER was effective and generally well tolerated when used to treat individuals with a range of epilepsy aetiologies in clinical practice, variability in its effectiveness and tolerability across the subgroups indicates that PER may be particularly useful for individuals with specific epilepsy aetiologies.

Atrioventricular Conduction in Mesial Temporal Lobe Seizures

Purpose: Asymmetric cerebral representation of autonomic function could help to stratify cardiac complications in people with epilepsy, as some seizures are associated with potentially deleterious arrhythmias including bradycardia and atrioventricular (AV) conduction block. We investigated seizure-related changes in AV conduction and ascertained whether these alterations depend on the hemisphere in mesial temporal lobe epilepsy (mTLE).

Methods: EEG and ECG data of people with pharmacoresistant mTLE undergoing pre-surgical video-EEG telemetry with seizures independently arising from both hippocampi, as determined by intracranial depths electrodes were reviewed. RR and PR intervals were measured using one-lead ECG. Statistics were done with paired student's t-tests and linear regression analysis. Data are given as mean ± SD.

Results: Fifty-six seizures of 14 patients (5 men, age 34.7 ± 9.8 years) were included (2 seizures per hemisphere and patient). There were no differences of absolute PR intervals and HR before and during unilateral ictal activity between left- and right-sided hippocampal seizures. Peri-ictal modulation of AV conduction, however, appeared greater with left-sided seizures, as the slope of the PR/HR correlations was significantly steeper with seizures originating in the left hippocampus. PR lengthening >200 ms or full block did not occur in any seizure.

Conclusions: Our data show that on average, PR intervals shortens with mesial temporal lobe seizures with more prominent effects in seizures with left-sided onset, supporting the notion of lateralized cerebral control of cardiac function. The clinical relevance of this subtle finding is unclear but may indicate a lateralized susceptibility to seizure-related AV node dysfunction in mTLE.

European trends in epilepsy surgery

OBJECTIVE

Resective surgery is effective in treating drug-resistant focal epilepsy, but it remains unclear whether improved diagnostics influence postsurgical outcomes. Here, we compared practice and outcomes over 2 periods 15 years apart.

METHODS

Sixteen European centers retrospectively identified 2 cohorts of children and adults who underwent epilepsy surgery in the period of 1997 to 1998 (n = 562) or 2012 to 2013 (n = 736). Data collected included patient (sex, age) and disease (duration, localization and diagnosis) characteristics, type of surgery, histopathology, Engel postsurgical outcome, and complications, as well as imaging and electrophysiologic tests performed for each case. Postsurgical outcome predictors were included in a multivariate logistic regression to assess the strength of date of surgery as an independent predictor.

RESULTS

Over time, the number of operated cases per center increased from a median of 31 to 50 per 2-year period (p = 0.02). Mean disease duration at surgery decreased by 5.2 years (p < 0.001). Overall seizure freedom (Engel class 1) increased from 66.7% to 70.9% (adjusted p = 0.04), despite an increase in complex surgeries (extratemporal and/or MRI negative). Surgeries performed during the later period were 1.34 times (adjusted odds ratio; 95% confidence interval 1.02-1.77) more likely to yield a favorable outcome (Engel class I) than earlier surgeries, and improvement was more marked in extratemporal and MRI-negative temporal epilepsy. The rate of persistent neurologic complications remained stable (4.6%-5.3%, p = 0.7).

CONCLUSION

Improvements in European epilepsy surgery over time are modest but significant, including higher surgical volume, shorter disease duration, and improved postsurgical seizure outcomes. Early referral for evaluation is required to continue on this encouraging trend.