Effectiveness of antiepileptic drug combination therapy for partial-onset seizures based on mechanisms of action

A practical guide to combination advanced therapy in inflammatory bowel disease

PURPOSE OF REVIEW

To provide an overview of the current literature regarding the use of advanced combination therapy (ACT) in patients with inflammatory bowel disease (IBD). Although the treatment of IBD has come a long way, many patients do not respond or will lose response to currently available treatments over time. ACT has been proposed as a model to create sustained remission in difficult-to-treat IBD patient populations. This review discusses the available literature supporting the use of ACT, followed by practical tips for applying this model of treatment to clinical practice.

RECENT FINDINGS

Both observational and controlled evidence have demonstrated that there may be an increased benefit of ACT in specific IBD patient populations compared to advanced targeted immunomodulator (TIM) monotherapy. Additional data is required to understand how to best use combination TIMs and the long-term risks associated with this strategy.

SUMMARY

While the literature has demonstrated the potential for benefit in both Crohn's disease and ulcerative colitis, the use of ACT is currently off-label and long-term controlled data is needed. The successful application of ACT requires careful consideration of both patient and disease profiles as well as close monitoring of treatment response and adverse events.

Efficacy, safety, and tolerability of adjunctive brivaracetam in adult Asian patients with uncontrolled focal-onset seizures: A phase III randomized, double-blind, placebo-controlled trial

OBJECTIVE

Evaluate efficacy, safety, and tolerability of adjunctive brivaracetam (BRV) in adult Asian patients with focal-onset seizures (FOS).

METHODS

Phase III, randomized, double-blind, placebo-controlled study (EP0083; NCT03083665) evaluating BRV 50 mg/day and 200 mg/day in patients (≥16-80 years) with FOS with/without secondary generalization (focal to bilateral tonic-clonic seizures) despite current treatment with 1 or 2 concomitant antiseizure medications. Following an 8-week baseline, patients were randomized 1:1:1 to placebo, BRV 50 mg/day, or BRV 200 mg/day, and entered a 12-week treatment period. Efficacy outcomes: percent reduction over placebo in 28-day FOS frequency (primary); 50% responder rate in FOS frequency; median percent reduction in FOS frequency from baseline; seizure freedom during treatment period (secondary). Primary safety endpoints: incidences of treatment-emergent adverse events (TEAEs); TEAEs leading to discontinuation; serious TEAEs.

RESULTS

In this study, 448/449 randomized patients (mean age, 34.5 years; 53.8% female) received ≥1 dose of study medication (placebo/BRV 50 mg/BRV 200 mg/day: n = 149/151/148). Percent reduction over placebo in 28-day adjusted FOS frequency was 24.5% (p = 0.0005) and 33.4% (p < 0.0001) with BRV 50 mg/day and 200 mg/day, respectively, 50% responder rate was 19.0%, 41.1%, and 49.3% with placebo, BRV 50 mg/day, and BRV 200 mg/day, respectively (p < 0.0001 for both BRV groups vs. placebo). Median percent reduction in FOS frequency from baseline was 21.3%/38.9%/46.7% in patients on placebo/BRV 50 mg/BRV 200 mg/day, respectively. Overall, 0, 7 (4.6%), and 10 (6.8%) patients were classified as seizure-free during the treatment period on placebo, BRV 50 mg/day, and BRV 200 mg/day, respectively (p = 0.0146/p = 0.0017 for BRV 50 mg/200 mg/day vs. placebo, respectively). TEAE incidences were similar between patients on placebo (58.4%) and all patients receiving BRV (58.5%); TEAE incidences for BRV 50 mg/day and BRV 200 mg/day were 57.0% and 60.1%, respectively. Overall, 0.7% of patients on placebo and 2.0% of all patients on BRV reported serious TEAEs (incidences for BRV 50 mg/day and BRV 200 mg/day were 1.3% and 2.7%, respectively), 20.1% of patients on placebo and 33.1% of all patients on BRV reported drug-related TEAEs (incidences for BRV 50 mg/day and BRV 200 mg/day were 26.5% and 39.9%, respectively), and 4.7% of patients on placebo and 3.0% of all patients on BRV discontinued due to TEAEs (discontinuation incidences for BRV 50 mg/day and BRV 200 mg/day were 2.6% and 3.4%, respectively).

SIGNIFICANCE

Adjunctive BRV was efficacious and well tolerated in adult Asian patients with FOS. Efficacy and safety profiles were consistent with BRV studies in predominantly non-Asian populations.

PLAIN LANGUAGE SUMMARY

Brivaracetam is used to treat partial or focal seizures in people with epilepsy. Most studies with brivaracetam tablets have involved people from non-Asian racial backgrounds. In this study, 449 Asian adults with epilepsy took part. One third took 50 mg of brivaracetam, one third took 200 mg of brivaracetam, and one third took a placebo each day for 12 weeks. On average, those who took brivaracetam had fewer seizures than those given the placebo. Most of the side effects were mild and the number and type of side effects seen were as expected for this medication.

Economic Evaluation of HLA-B*15:02 Genotyping for Asian Australian Patients With Epilepsy

Importance

The HLA-B*15:02 allele has been associated with an increased risk of carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis in specific Asian populations (including Han Chinese, Malaysian, Thai, and Vietnamese individuals). While HLA-B*15:02 genotype testing in Asian populations is recommended by several international prescribing guidelines, it is not subsidized by the Medicare Benefits Schedule in Australia.

Objective

To evaluate the cost-effectiveness of HLA-B*15:02 genotyping in Asian Australian patients with epilepsy.

Design, Setting, and Participants

A model with components of decision analysis and Markov simulation was developed to simulate clinical trajectories of adult Asian Australian patients with newly diagnosed epilepsy being considered for carbamazepine treatment. Cost-effectiveness and cost-utility analyses over a lifetime time horizon were conducted from the perspective of the Australian health care sector. The study was conducted in May 2023 and data analysis was performed from August 2023 to November 2023.

Intervention

No HLA-B*15:02 genotyping and the empirical initiation of treatment with carbamazepine vs HLA-B*15:02 genotyping and the initiation of treatment with valproate in allele carriers.

Main Outcomes and Measures

Life-years (LYs), quality-adjusted life-years (QALYs), and costs in 2023 Australian dollars (A$); incremental cost-effectiveness ratios.

Results

HLA-B*15:02 screening was associated with an additional mean cost of A$114 (95% CI, -A$83 to A$374; US$76; 95% CI, -US$55 to US$248) and a reduction in 0.0152 LYs (95% CI, 0.0045 to 0.0287 LYs) but improvement by 0.00722 QALYs (95% CI, -0.0247 to -0.01210) compared with no screening, resulting in an incremental cost-effectiveness ratio of A$15 839 per QALY gained (US$10 523 per QALY). Therefore, universal genotyping for Asian Australian individuals was cost-effective compared with current standards of practice at the A$50 000 per QALY willingness-to-pay threshold. Sensitivity analyses demonstrated that the intervention remained cost-effective across a range of costs, utilities, transition probabilities, and willingness-to-pay thresholds. At the A$50 000 per QALY willingness-to-pay threshold, universal screening was the preferred strategy in 88.60% of simulations.

Conclusions and Relevance

The results of this economic evaluation suggest that HLA-B*15:02 screening represents a cost-effective choice for Asian Australian patients with epilepsy who are being considered for treatment with carbamazepine.

Impact of Polytherapy on Memory Functioning in Patients With Drug-Resistant Epilepsy: The Role of Attention and Executive Functions

OBJECTIVE

The aim was to examine the effect of polytherapy (i.e., the number of administered anti-seizure medications (ASMs)) on memory, and whether the interaction between the number of ASMs and attentional/executive functioning affect presurgical memory functioning and postsurgical memory changes in patients with drug-resistant epilepsy.

METHODS

Two studies were carried out. Study 1 consisted of a presurgical assessment of 125 adult patients, in which attention/executive function (EpiTrack screening tool) and memory were assessed (cross-sectional study). Of them, 72 patients underwent a second postsurgical evaluation, in which memory was assessed (Study 2). Patients were distributed into groups based on EpiTrack performance and number of ASMs.

RESULTS

The interaction between the number of ASMs and the attentional/executive functioning significantly affected presurgical memory, with patients with impaired EpiTrack performance taking three-four ASMs having poorer scores than patients with intact EpiTrack performance taking three-four ASMs (for all, p < .0001). This interaction also affected postsurgical memory changes, with patients with impaired Epitrack performance taking three-four ASMs having higher postsurgical decline than those with intact Epitrack performance taking three-four ASMs (for all, p < .005). No differences were found in patients taking two ASMs. Furthermore, the number of ASMs was associated with presurgical memory performance and postsurgical memory changes only in patients with impaired EpiTrack performance (for all, p < .05).

CONCLUSIONS

Our findings underline the utility of EpiTrack, together with the clinical information on the number of prescribed ASMs, to corroborate the impact of polytherapy on memory and to optimize the prediction of postsurgical memory changes.

Efficacy and safety of adjunctive cenobamate based on patient etiology: Post-hoc analysis of YKP3089C017 randomized clinical trial

INTRODUCTION

Adjunctive cenobamate was effective and safe for the treatment of uncontrolled focal onset seizures in a randomized, double-blind, placebo-controlled, phase 2 study (YKP3089C017; NCT01866111). This post-hoc analysis assessed the efficacy of adjunctive cenobamate in the treatment of patients with different epileptic etiologies during the study.

METHODS

Adult patients with uncontrolled focal seizures who previously received 1 to 3 antiseizure medications (ASMs) were randomly assigned in a ratio of 1:1:1:1 to receive placebo or cenobamate 100, 200 or 400 mg/day. Patients were further stratified based on their etiologic causes as genetic/presumed genetic, unknown cause, structural cause, and not reported (NR) groups. The frequency per 28 days for an 18-week double-blind treatment period, responder rates (≥50 %, ≥75 %, ≥90 %, and 100 %) during the maintenance phase (12 weeks), and safety were assessed.

RESULTS

A total of 394 patients were categorized into the genetic/presumed genetic (n = 9; 2.28 %), unknown cause (n = 199; 50.51 %), structural cause (n = 177; 44.92 %), and NR (n = 13; 3.30 %) groups, with 4 patients were classified into either of the two etiological causes each. The baseline characteristics were comparable. The percentage of reduction in seizure frequency per 28 days was significantly higher in the cenobamate-treated structural (p = 0.01) and unknown cause (p = 0.0003) groups compared with the placebo group. Responder rates of ≥50 %, ≥75 %, ≥90 %, and 100 % were also higher with cenobamate therapy. Notably, no serious treatment-emergent adverse events (TEAEs) were observed in the genetic/presumed genetic group treated with cenobamate. The most common TEAEs (≥10 %) occurring in patients treated with cenobamate were nervous system disorders by system organ class, and somnolence was the most commonly reported TEAE.

CONCLUSION

Cenobamate reduces seizures in adult patients previously treated with ASMs, with high responder rates and acceptable safety, regardless of underlying causes.

A comparison of cenobamate with other newer antiseizure medications for adjunctive treatment of focal-onset seizures: A systematic review and network meta-analysis

PURPOSE

To compare the efficacy, safety, and tolerability of cenobamate with other newer anti-seizure medications (ASMs) including brivaracetam, eslicarbazepine, lacosamide, perampanel, and zonisamide, approved for adjunctive treatment of drug-resistant focal-onset seizures (FOS) in adults with epilepsy.

METHODS

A systematic literature review (SLR) was conducted to obtain relevant efficacy, safety, and tolerability data for ASMs for the treatment of drug-resistant FOS. All studies were thoroughly assessed for potential sources of heterogeneity and analysed via Bayesian network meta-analyses (NMAs). Efficacy outcomes were ≥50 % responder rate and seizure freedom during the maintenance period, which were modelled simultaneously using a multinomial Bayesian NMA. Safety and tolerability outcomes were the proportion of patients who experienced at least one treatment-emergent adverse event (TEAE) and the proportion who experienced at least one TEAE leading to discontinuation.

RESULTS

The SLR identified 76 studies, of which 23 were included in the Bayesian NMAs. Cenobamate was associated with statistically significant higher rates for the ≥50 % responder rate and seizure freedom outcomes compared with all ASMs analysed. The point estimates indicated that cenobamate was associated with higher rates of experiencing at least one TEAE and at least one TEAE leading to discontinuation compared with brivaracetam, lacosamide, and zonisamide; however, no results were statistically significant.

CONCLUSION

Cenobamate was associated with increased efficacy compared with all ASMs analysed. There were no statistically significant differences in the safety and tolerability outcomes. The results presented corroborate the conclusions drawn from previous published NMAs, which also highlight the notable efficacy of cenobamate in comparison with other ASMs.

Which terms should be used to describe medications used in the treatment of seizure disorders? An ILAE position paper

A variety of terms, such as "antiepileptic," "anticonvulsant," and "antiseizure" have been historically applied to medications for the treatment of seizure disorders. Terminology is important because using terms that do not accurately reflect the action of specific treatments may result in a misunderstanding of their effects and inappropriate use. The present International League Against Epilepsy (ILAE) position paper used a Delphi approach to develop recommendations on English-language terminology applicable to pharmacological agents currently approved for treating seizure disorders. There was consensus that these medications should be collectively named "antiseizure medications". This term accurately reflects their primarily symptomatic effect against seizures and reduces the possibility of health care practitioners, patients, or caregivers having undue expectations or an incorrect understanding of the real action of these medications. The term "antiseizure" to describe these agents does not exclude the possibility of beneficial effects on the course of the disease and comorbidities that result from the downstream effects of seizures, whenever these beneficial effects can be explained solely by the suppression of seizure activity. It is acknowledged that other treatments, mostly under development, can exert direct favorable actions on the underlying disease or its progression, by having "antiepileptogenic" or "disease-modifying" effects. A more-refined terminology to describe precisely these actions needs to be developed.

Efficacy and tolerability of perampanel: a Chinese real-world observational study in epilepsy

Purpose

To investigate whether there exists a statistically significant distinction between the effectiveness and tolerance of perampanel (PER) and the number of antiseizure medications (ASMs) that were tried prior to administering PER.

Method

A prospective, observational study was performed at West China Hospital of Sichuan University. The study included patients diagnosed with epilepsy who were prescribed PER and were monitored for a minimum of 6 months. The efficacy of PER was evaluated at 1, 3, 6, and 12-month intervals by examining the retention rate and the 50% response rate. All statistical analyses were conducted using IBM SPSS Statistics version 25 (IBM Corporation, Armonk, New York).

Results

A total of 1,025 patients were identified, of which 836 were included in the analysis. Seven hundred and eighty-nine patients (94.4%) were followed up for a year. The median age of the patients was 29.32 ± 14.06 years, with 45.81% of the patients being male and 17.0% being adolescents. The average duration of epilepsy was 11.22 ± 8.93 years. Overall, PER was discontinued in 49.5% of patients, with the most common reasons being inadequate therapeutic effect and treatment-emergent adverse events (TEAEs). At the 6-month follow-up, the retention rate was 54.2% (454/836), and 39.6% of patients had a 50% response. At the 12-month follow-up, the retention rate was 49.4% (340/789), and 44.5% of patients had a 50% response. Patients who received PER as monotherapy had the highest retention rates (P = 0.034) and 50% response rates (P < 0.001) at any follow-up point. TEAEs were reported in 32.0% of patients, and these led to discontinuation in 15.4% of patients. The most common TEAEs were dizziness and somnolence. There was no significant difference between subgroups (P = 0.57), but there was a significant difference between the dosage of PER and TEAEs (P < 0.001).

Main findings

The study concludes that PER is effective in treating both focal and generalized tonic-clonic seizures. Patients who had fewer previous exposures to ASMs exhibited higher response rates to PER. TEAEs related to PER dosage were more prevalent during the first 3 months of treatment and tended to improve with continued use, ultimately demonstrating favorable long-term tolerability.

Cenobamate in refractory epilepsy: Overview of treatment options and practical considerations

Management of drug resistant epilepsy (DRE) represents a challenge to the treating clinician. This manuscript addresses DRE and provides an overview of treatment options, medical, surgical, and dietary. It addresses treatment strategies in polytherapy, then focuses on the role cenobamate (CNB) may play in reducing the burden of DRE while providing practical advice for its introduction. CNB is a recently approved, third generation, anti-seizure medication (ASM), a tetrazole-derived carbamate, thought to have a dual mechanism of action, through its effect on sodium channels as well as on GABAA receptors at a non-benzodiazepine site. CNB, having a long half-life, is an effective add-on ASM in refractory focal epilepsy with a higher response rate and a higher seizure-freedom rate than is usually seen in regulatory clinical trials. Experience post-licensing, though still limited, supports the findings of clinical trials and is encouraging. Its spectrum of action in relation to generalized epilepsies and seizures remains to be established, and there are no data on its efficacy in monotherapy. At the time of writing, CNB has been prescribed for some 50 000 individuals with DRE and focal epilepsy. A larger number is needed to fully establish its safety profile. It should at all times be introduced slowly to minimize the risk of serious allergic drug reactions. It has clinically meaningful interactions which must be anticipated and managed to maximize tolerability and likelihood of successful treatment. Despite the above, it may well prove to be of major benefit in the treatment of many patients with drug resistant epilepsy.

Optimizing treatment persistence in epilepsy: a comparative analysis of combined antiseizure medications with different mechanisms of action

Background

Combination therapy with antiseizure medications (ASMs) is a rational strategy if monotherapy cannot effectively control seizures, thereby aiming to improve tolerance and treatment persistence.

Objectives

To compare the efficacy of different ASM combinations among patients.

Design

Patients with epilepsy on monotherapy who had a second ASM added as concomitant two-drug therapy from January 2009 to May 2019 in the Chang Gung Research Database, Taiwan, were included in the analysis.

Methods

ASM combinations were compared based on their primary mechanism of action (MoA) which are as follows: gamma-aminobutyric acid receptor (G), sodium channel blocker (SC), synaptic vesicle protein 2A (SV2), calcium channel blocker (C), and multiple mechanisms (M). Treatment persistence was compared, and the predictors of persistence were analyzed.

Results

In total, 3033 patients were enrolled in this study. Combined ASMs with different MoAs had significantly longer treatment persistence than ASMs with similar MoAs, specifically SC and M combinations. Patients receiving combined ASMs with different MoAs were less likely to discontinue treatment [adjusted hazards ratio: 0.83 (95% CI: 0.75-0.93), p < 0.001]. Among all combinations, the SC + SV2 combination had the longest treatment persistence (mean ± SD: 912.7 ± 841.6 days). Meanwhile, patients receiving the G combination had a higher risk of treatment discontinuation than those receiving the SC + SV2 combination. Underlying malignancies were associated with an increased risk of treatment discontinuation across all MoA categories. Male patients receiving the SC, SV2, and M combinations were more likely to discontinue treatment than female patients. Moreover, patients with renal disease were more likely to discontinue treatment with the SV2 combinations.

Conclusion

ASM combinations with different MoAs had superior efficacy and tolerability to ASM combinations with similar MoAs, particularly SC and M combinations. In our cohort, factors associated with treatment discontinuation included underlying malignancy, male sex, and renal disease. These findings may provide valuable insights into the use of ASM combinations if monotherapy cannot adequately control seizures.

Efficacy and tolerability of lacosamide as adjunctive therapy in patients with focal-onset seizures: an observational, prospective study

PURPOSE

To evaluate the efficacy and tolerability of adjunctive lacosamide (LCM) in patients with focal-onset seizures, with or without combined secondarily generalized seizures.

METHODS

106 patients aged ≥ 16 years were recruited consecutively in this single-center prospective observational study. All patients received LCM as an add-on treatment on the basis of clinical judgement. Seizure frequency, adverse events (AEs) and retention rates were obtained at 3 and 6 months after LCM introduction.

RESULT

The overall response rates were 53.3 and 70.4% after 3 and 6 months, respectively, and the freedom of seizures at the same points was reached at 19 and 26.5%. The retention rates were 99.1% at the 3-month follow-up and 93.3% at the 6-month follow-up. The overall incidence of adverse events was 35.8%. The leading AEs were dizziness (16.98%) and sedation (6.6%).

CONCLUSIONS

Our study confirmed the efficacy and tolerability of adjunctive LCM in Chinese patients in real-life conditions. Based on our treatment experience, a universal maintenance dose of LCM would be needed in Chinese patients.

Should substitution monotherapy or combination therapy be used after failure of the first antiseizure medication? Observations from a 30-year cohort study

OBJECTIVES

To assess the temporal trends in the use of second antiseizure (ASM) regimens and compare the efficacy of substitution monotherapy and combination therapy after failure of initial monotherapy in people with epilepsy.

METHODS

This was a longitudinal observational cohort study conducted at the Epilepsy Unit of the Western Infirmary in Glasgow, Scotland. We included patients who were newly treated for epilepsy with ASMs between July 1982, and October 2012. All patients were followed up for a minimum of 2 years. Seizure freedom was defined as no seizure for at least 1 year on unchanged medication at the last follow up.

RESULTS

During the study period, 498 patients were treated with a second ASM regimen after failure of the initial ASM monotherapy, of whom 346 (69%) were prescribed combination therapy and 152 (31%) were given substitution monotherapy. The proportion of patients receiving second regimen as combination therapy increased during the study period from 46% in first epoch (1985-1994) to 78% in the last (2005-2015) (RR = 1.66, 95% CI: 1.17-2.36, corrected-p = .010). Overall, 21% (104/498) of the patients achieved seizure freedom on the second ASM regimen, which was less than half of the seizure-free rate on the initial ASM monotherapy (45%, p < .001). Patients who received substitution monotherapy had similar seizure-free rate compared with those who received combination therapy (RR = 1.17, 95% CI: 0.81-1.69, p = .41). Individual ASMs used, either alone or in combination, had similar efficacy. However, the subgroup analysis was limited by small sample sizes.

SIGNIFICANCE

The choice of second regimen used based on clinical judgment was not associated with treatment outcome in patients whose initial monotherapy failed due to poor seizure control. Alternative approaches such as machine learning should be explored to aid individualized selection of the second ASM regimen.

Time to baseline seizure count in patients with focal seizures receiving adjunctive eslicarbazepine acetate in a phase IV clinical trial

BACKGROUND

The efficacy and tolerability of eslicarbazepine acetate (ESL), a once-daily, orally-administered, anti-seizure medication (ASM), have primarily been established in treatment-resistant epilepsy patients, the population most often enrolled in clinical trials of anti-seizure medications. More recently, ESL was also shown to be effective and well-tolerated as first adjunctive therapy in non-treatment-resistant patients in an open-label, non-randomized, Phase IV, 24-week study of ESL using standard efficacy parameters in adults with focal seizures.

OBJECTIVE

To determine the time required to reach baseline seizure count, as an alternative method of assessing the efficacy of adjunctive ESL in patients with relatively low baseline monthly seizure frequencies. This additional analysis was undertaken, as subtle changes and improvements are difficult to analyze using standard efficacy parameters, such as standardized seizure frequency reduction when the baseline frequency of seizures is particularly low.

METHODS

This was a post-hoc analysis of the Phase IV study data, which investigated time to baseline seizure count in patients aged ≥ 18 years with focal seizures as an alternative measure of anti-seizure efficacy. In the Phase IV trial, patients had been enrolled into 2 groups: Arm 1: ESL as first adjunctive therapy to levetiracetam (LEV) or lamotrigine (LTG), the two most commonly-prescribed ASMs, in patients with inadequate response to treatment; Arm 2: ESL as a later adjunctive therapy, following prior use of 1-2 ASMs in patients who required an additional therapeutic option.

RESULTS

The time to reach individual baseline seizure count was longer in patients with focal seizures receiving ESL as a first (Arm 1) versus later (Arm 2) adjunctive therapy (p = 0.005). Patients who received ESL as a first adjunctive therapy had a longer time to ESL discontinuation than patients who received ESL as a later adjunctive therapy (p = 0.04). In Arm 1, patients receiving concomitant LTG reported treatment-emergent adverse events (TEAEs) significantly earlier than those receiving LEV (p = 0.02). Compared to patients receiving concomitant LTG, a greater number of patients in Arm 1 who were taking concomitant LEV had a modal ESL dose > 1200 mg and completed the full maintenance period. A greater number of patients in Arm 1 who were receiving concomitant LEV and completed the 24-week maintenance period reached a maximum ESL dose of 1600 mg, compared to those taking LTG, who reached a maximum ESL dose of 1200 mg.

CONCLUSIONS

This analysis of the Phase IV clinical trial data provides an alternative way of assessing efficacy beyond standardized seizure frequency reduction, in the context of relatively low monthly median seizure frequencies at baseline (SSF 2.0-2.4). These results provide further support for the use of ESL as an earlier or later adjunctive therapy to LEV or LTG.

Effectiveness and tolerability of adjunctive perampanel in the treatment of pediatric patients with uncontrolled epilepsy: A retrospective, single-center, real-world study

OBJECTIVE

The main aim of this study was to assess the efficacy, safety, and tolerability of adjunctive perampanel (PER) in the treatment of children and adolescents with epilepsy.

METHODS

Pediatric patients who visited the pediatric epilepsy clinic of Henan Provincial People's Hospital between May 2020 and December 2021 were recruited. All participants were treated with PER as adjunctive therapy and were seen routinely (minimum: a baseline and 12-week visit). The efficacy and tolerability of adjunctive PER for the treatment of epilepsy were investigated.

RESULTS

One hundred and fourteen patients were enrolled, among whom 7 (6.1%) were lost to follow-up. At 12 weeks, the responder rate and the seizure-free rate were 56.1% (60/107) and 32.7% (35/107), respectively. The responder rate increased with the duration of PER administration and was significantly higher when PER was used as an early add-on (after ≤2 prior antiseizure medications (ASMs)) than a late add-on (after >2 prior ASMs). However, there was no significant difference in the treatment efficacy of adjunctive PER in patients with different epilepsy etiologies or types. Adverse events, including irritability, dizziness, somnolence, ataxic gait, weight gain, and tinnitus, were reported in thirty-two patients (29.9%).

CONCLUSIONS

In a routine clinical setting of pediatric patients with epilepsy, good effectiveness and tolerability of adjunctive PER were demonstrated. Notably, patients initiating PER as an early add-on showed a better seizure outcome than those initiating PER as a late add-on.

Cognitive functioning, cerebrospinal fluid Alzheimer's disease biomarkers and cerebral glucose metabolism in late-onset epilepsy of unknown aetiology: A prospective study

Epilepsy is increasing, being more common in older adults, with more than 20% of late-onset cases with unknown aetiology (LOEU). Although epilepsy was associated with cognitive impairment, few studies evaluated the trajectories of cognitive decline in patients with LOEU. The present study aimed at assessing biomarkers of Alzheimer's disease (AD) in patients with LOEU and evaluating their cognitive performance for 12 months. For this study, 55 patients diagnosed with LOEU and 21 controls were included. Participants underwent cognitive evaluation and cerebrospinal fluid (CSF) biomarker analysis (ß-amyloid₄₂ , tau proteins) before starting anti-seizure medication and then repeated the cognitive evaluation at the 12-month follow-up. A subgroup of LOEU patients and controls also performed ¹⁸ F-fluoro-2-deoxy-D-glucose positron emission tomography (¹⁸ F-FDG PET) before starting anti-seizure medication. At baseline, LOEU patients showed lower Mini-Mental State Examination (MMSE) score, worse cognitive performance in several domains, lower β-amyloid₄₂ and higher tau proteins CSF levels than controls. Significantly reduced glucose consumption was observed in the right posterior cingulate cortex and left praecuneus areas in LOEU patients than controls, and this finding correlated with memory impairment. In the longitudinal analysis, a significant decrease in MMSE and an increase in verbal fluency scores were found in LOEU patients. These findings evidence that LOEU patients have a significant cognitive impairment, and alteration of cerebral glucose consumption and CSF AD biomarkers than controls. Moreover, they showed a progressive global cognitive decline at follow-up, although verbal fluency was preserved. Further studies are needed to better understand the pathophysiological aspects of LOEU and its association with AD.

Perampanel as adjunctive therapy in drug resistant epilepsy in adolescents and children waiting for epilepsy surgery: A multicenter observational study in Thailand

PURPOSE

To evaluate the effectiveness and tolerability of perampanel (PER) in real-world settings in patients between 1 month and 18 years of age with drug resistant epilepsy (DRE) waiting for epilepsy surgery.

METHODS

In this multicenter study, patients between 1 month and 18 years of age with DRE treated with PER between January 2020 and June 2021 were selected. The study outcome was effectiveness of PER treatment reported as reduction in seizure frequency and seizure freedom rate. Effectiveness was assessed at 30, 60, 90, 120, 150 and 180 days after initiation of PER. Tolerability profiles were reported as adverse events according to the observations of the patients' family members and physician.

RESULTS

Eighty-five patients treated with PER were included in the study. The mean initial dose and mean maximum dose of adjunctive PER was 2 mg/day and 5.8 mg/day, respectively. The mean seizure frequency (rate/week) was 41.3, 25.4, 18.9, 14.3, 11.2, 11.1 and 8.9 seizures at baseline, 30, 60, 90, 120, 150 and 180 days, respectively; the reduction in the mean seizure frequency at all timepoints was significant compared at the baseline (p<0.001). At 180 days, ≥75% seizure reduction was seen in 64.9% (37/57) of the patients and seizure freedom was achieved in 36.8% (21/57). Drowsiness, ataxia, and behavioral changes were the common adverse events observed, and these improved after the dose of PER was reduced. No discontinuation of PER was required due to side effects or intolerance.

CONCLUSION

In real-world settings, PER is well tolerated and effective in seizure control in pediatric and adolescent patients with DRE.

Approach to the Medical Treatment of Epilepsy

PURPOSE OF REVIEW

This article discusses the use of antiseizure medications in the treatment of focal and generalized epilepsies using an evidence-based approach.

RECENT FINDINGS

In recent years, several new antiseizure medications with differing mechanisms of action have been introduced in clinical practice, and their efficacy and safety has been evaluated in randomized controlled clinical trials. Currently, all antiseizure medications can prevent seizure occurrence, but they have no proven disease-modifying or antiepileptogenic effects in humans. The choice of therapy should integrate the best available evidence of efficacy, tolerability, and effectiveness derived from clinical trials with other pharmacologic considerations, the clinical expertise of the treating physicians, and patient values and preferences. After the failure of a first antiseizure medication, inadequate evidence is available to inform policy. An alternative monotherapy (especially if the failure is because of adverse effects) or a dual therapy (especially if failure is because of inadequate seizure control) can be used.

SUMMARY

Currently, several antiseizure medications are available for the treatment of focal or generalized epilepsies. They differ in mechanisms of action, frequency of administration, and pharmacologic properties, with a consequent risk of pharmacokinetic interactions. Major unmet needs remain in epilepsy treatment. A substantial proportion of patients with epilepsy continue to experience seizures despite two or more antiseizure medications, with a negative impact on quality of life. Therefore, more antiseizure medications that could provide higher seizure control with good tolerability and that could positively affect the underlying disease are needed.

Update on Antiseizure Medications 2022

EDITORS NOTE

The article "Update on Antiseizure Medications 2022" by Dr Abou-Khalil was first published in the February 2016 Epilepsy issue of Continuum: Lifelong Learning in Neurology as "Antiepileptic Drugs," and at the request of the Editor-in-Chief was updated by Dr Abou-Khalil for the 2019 issue and again for this issue.

A scoping review on cannabidiol therapy in tuberous sclerosis: Current evidence and perspectives for future development

Cannabidiol (CBD) has recently been approved as an add-on therapy by various regulatory agencies for tuberous sclerosis complex (TSC)-associated seizures based on its short-term efficacy and safety in a pivotal randomized controlled trial. However, critical information about which patients with TSC and seizure types respond best to CBD (clinical, electrophysiological, and genetic predictors of responsiveness), when to use CBD in the treatment algorithm, and how CBD can be combined with other antiseizure medications (ASMs) in the form of a rational polypharmacy therapy is still lacking. In general, there is a limited in-depth critical review of CBD for the treatment of TSC to facilitate its optimal use in a clinical context. Here, we utilized a scoping review approach to report the current evidence of efficacy and safety of pharmaceutical-grade CBD in patients with TSC, including relevant mechanism of action and drug-drug interactions with other ASMs. We also discussed emerging information about CBD's long-term efficacy and safety data in patients with TSC. Finally, we discussed some critical unanswered questions in several domains related to effective clinical management of TSC using CBD, including barriers to early and aggressive treatment in infants, difficulty with universal access to CBD, a lack of studies to understand CBD's impact on seizure severity and specific seizure types, insufficient exploration of CBD in TSC-related cognitive and behavioral issues, and the need for more research into CBD's effects on various biomarkers.

Clinical profile, treatment modalities, and outcomes in patients with infantile spasms: A retrospective study from the United Arab of Emirates (UAE)

BACKGROUND

Infantile spasms (IS) are an epileptic encephalopathy where the prognosis is generally poor, with most patients exhibiting psychomotor retardation or intractable epilepsy. However, it is claimed that early and aggressive treatment is related to better response rate and outcome, especially in patients with idiopathic IS.

OBJECTIVE

To investigate different treatment modalities and outcomes in patients with IS attending a pediatric neurology clinic at a specialized neurology center in Abu Dhabi, United Arab Emirates.

METHODS

Retrospective chart review was done for detailed history, demographic data, etiology, neuro-diagnostic workup, treatment modalities, and the outcomes for all patients diagnosed with IS from September 2014 to September 2019.

RESULTS

Three treatment modalities were identified as 1st line- Prednisolone United Kingdom Infantile Spasms Study (UKISS) (N = 15, 46.8%), Anti-Seizure Medications (ASMs) (N = 12, 37.5%), and Vigabatrin (N = 5, 15.6%). The complete response rate to Vigabatrin as a 1st line treatment showed the highest statistical significance (X² = 7.34, p = 0.007). Patients with idiopathic IS showed a comparable response to treatment to those with symptomatic IS. Additional response to 2nd line treatment with Prednisolone UKISS protocol (25%) and Vigabatrin (15%) was noted in patients who showed partial or no response to the 1st line treatment. None of our patients received Adrenocorticotropic Hormone as treatment. All patients with desirable final outcomes were with idiopathic IS and none were symptomatic.

CONCLUSION

More than a third of our patients showed poor treatment response whenever they were not offered treatment according to the current available protocols. This indicates an urgent need for having a unified treatment protocol that takes into consideration the availability of medications, professional expertise as well as diagnostic workup outside major tertiary care centers in our region.

Thymoquinone Potentiates the Effect of Phenytoin against Electroshock-Induced Convulsions in Rats by Reducing the Hyperactivation of m-TOR Pathway and Neuroinflammation: Evidence from In Vivo, In Vitro and Computational Studies

Epilepsy is a chronic neurodegenerative disease characterized by multiple seizures, hereto 35% of patients remain poor responders. Phenytoin (PHT; 20 and 40 mg/kg) and thymoquinone (THQ; 40 and 80 mg/kg) were given alone and as a low dose combination for 14 days (p.o), prior to challenge with maximal electroshock (MES; 180 mA, 220 V, 0.2 s). Apart from observing convulsions, hippocampal mTOR, IL-1β, IL-6 and TNF-α levels were measured. Hippocampal histomorphological analysis was also conducted. In vitro cell line studies and molecular docking studies were run in parallel. The results revealed the synergistic potential of the novel duo-drug combination regimen: PHT (20 mg/kg) and THQ (40 mg/kg) against MES-induced convulsions. MES amplified signaling through mTOR, and inflated the levels of proinflammatory markers (IL-1β, IL-6 and TNF-α), which was significantly averted (p < 0.001) with the said drug combination. The computational studies revealed that PHT and THQ cooperatively bind the active site on Akt (upstream target of m-TOR) and establish a good network of intermolecular interactions, which indicates the sequential inhibition of PI3K/Akt/m-TOR signaling with the combination. The combination also increased cell viability by 242.81% compared to 85.66% viability from the the toxic control. The results suggest that the PHT and THQ in combination possesses excellent anticonvulsant and neuroprotective effects.

Single-Target Versus Multi-Target Drugs Versus Combinations of Drugs With Multiple Targets: Preclinical and Clinical Evidence for the Treatment or Prevention of Epilepsy

Rationally designed multi-target drugs (also termed multimodal drugs, network therapeutics, or designed multiple ligands) have emerged as an attractive drug discovery paradigm in the last 10-20 years, as potential therapeutic solutions for diseases of complex etiology and diseases with significant drug-resistance problems. Such agents that modulate multiple targets simultaneously are developed with the aim of enhancing efficacy or improving safety relative to drugs that address only a single target or to combinations of single-target drugs. Although this strategy has been proposed for epilepsy therapy >25 years ago, to my knowledge, only one antiseizure medication (ASM), padsevonil, has been intentionally developed as a single molecular entity that could target two different mechanisms. This novel drug exhibited promising effects in numerous preclinical models of difficult-to-treat seizures. However, in a recent randomized placebo-controlled phase IIb add-on trial in treatment-resistant focal epilepsy patients, padsevonil did not separate from placebo in its primary endpoints. At about the same time, a novel ASM, cenobamate, exhibited efficacy in several randomized controlled trials in such patients that far surpassed the efficacy of any other of the newer ASMs. Yet, cenobamate was discovered purely by phenotype-based screening and its presumed dual mechanism of action was only described recently. In this review, I will survey the efficacy of single-target vs. multi-target drugs vs. combinations of drugs with multiple targets in the treatment and prevention of epilepsy. Most clinically approved ASMs already act at multiple targets, but it will be important to identify and validate new target combinations that are more effective in drug-resistant epilepsy and eventually may prevent the development or progression of epilepsy.

Perampanel Increases Cortical EEG Fast Activity in Child and Adult Patients Affected by Epilepsy: A Quantitative EEG Study

OBJECTIVE

Quantitative EEG (qEEG) is an established technique used as objective measure for evaluating the effect of antiseizure medications (ASMs) on EEG background activity and monitoring cognitive effects of ASMs. Perampanel (PER) has been associated with relatively more tolerable cognitive effects in patients with epilepsy. The primary aim of the present study was to verify the effect of PER as first add-on ASM on qEEG in child and adult patients affected by epilepsy. The secondary aim of this study was to verify the effectiveness of the drug as first add-on treatment in both child and adult patients with epilepsy.

METHODS

We collected data from 17 adults and 10 children treated with PER as first add-on treatment, who underwent qEEG analysis before starting PER and at 3-month follow-up under stable treatment.

RESULTS

PER resulted with significant effectiveness in reducing seizures in both children and adults. Considering qEEG analysis, we observed at follow-up the significant increase in beta1 and beta total bands both in children and adult patients. In particular, children showed the significant increase of beta band frequencies predominantly in the occipital regions, whereas adults showed a widespread increase of beta activity. Moreover, we documented in both child and adult patients the global reduction of delta bands activity.

CONCLUSIONS

This qEEG study documented the relative increase of cortical EEG fast activity in both children and adult patients affected by epilepsy and treated by PER. This result may suggest a potential less negative impact of PER on cognition in patients affected by epilepsy, other than demonstrating effectiveness of the drug when used as first add-on treatment in both children and adult patients.

How much can medical management alone improve the outcome of adult drug-resistant epilepsy? An exploratory study on possibilities and limitations of combining multiple therapeutic actions

PURPOSE

Failure to control epileptic seizures with two medications, adequately chosen and dosed, indicates drug-resistant epilepsy (DRE). The chance of pharmacologically controlling seizures is low for patients with DRE and uncontrolled seizures who are not candidates for surgery, who have already undergone surgery, or who already had a vagus nerve stimulator (VNS) placed. Patients experiencing these conditions must instead rely on medical management of their seizures, and there is no breakthrough solution on the horizon. Medical care of DRE might be optimized by systematically considering factors that promote and inhibit breakthrough seizures. For example, seizure control could be enhanced through measures such as increasing the frequency of follow-up visits, tracking treatment plan compliance, treating sleep disorders, rational polypharmacy, adjusting drug administration to achieve higher levels when seizures are more likely and educating patients on seizure triggers. A systematic and simultaneous implementation of all of these measures is likely to yield a sizable, clinically relevant, improvement. This paper presents an exploratory study on the effects of implementing such an approach, specifically evaluating this method's impact on seizure frequency.

METHODS

I performed a retrospective chart review of 659 consecutive adult patients with epilepsy followed up at the University of Utah and at the Salt Lake City VA Medical center using the multimodal approach described above. I identified 27 patients who had DRE and uncontrolled seizures and in whom a medical management optimization protocol was implemented. I measured these patients' seizure frequency at the beginning and the end of the study period and compared the results with those of a matching control group of 48 patients.

RESULTS

The optimization protocol did not increase the number of seizure-free patients with DRE; however, it was effective in minimizing seizure frequency in patients whose seizures remained uncontrolled. Among these patients, the median seizure frequency dropped by 64% in the optimization group but did not change in the control group.

CONCLUSIONS

Despite the high occurrence of DRE, there is no accepted protocol for the related medical management. This paper describes an effective approach that can be implemented in a clinically relevant and readily achievable manner.

Selection of antiseizure medications for first add-on use: A consensus paper

INTRODUCTION

When monotherapy used alone or sequentially fails to achieve seizure control, a trial of combination therapy may be considered.

OBJECTIVE

To define optimal criteria to guide choice of an antiseizure medication (ASM) for use as first add-on.

METHODS

A standardized Delphi procedure was applied to produce a list of consensus statements. First, an Expert Board consisting of 5 epileptologists agreed on a set of 46 statements relevant to the objective. The statements were then finalized through an iterative process by a Delphi Panel of 84 Italian pediatric and adult neurologists with expertise in the management of epilepsy. Panel members provided anonymous ratings of their level of agreement with each statement on a 9-point Likert scale.

RESULTS

Consensus, defined as agreement by at least 80% of Panel members, was reached for 36 statements. Medication-related factors considered to be important for drug selection included efficacy, tolerability and safety, interaction potential, mechanism of action, and ease of use. The need to optimize adherence and to tailor drug selection to individual characteristics was emphasized.

CONCLUSIONS

Choice of an ASM for first add-on requires consideration of many factors, many of which also apply to choose initial treatment. Factors more specifically relevant to add-on use include drug interaction potential and the preference for an ASM with a different mechanism of action.

Which treatment strategy in patients with epilepsy with focal seizures uncontrolled by the first anti-seizure medication?

There is no definite proven or accepted strategy in the management of patients with focal epilepsy uncontrolled by the first anti-seizure medication (ASM). Clinical studies failed to find a significant difference in efficacy or tolerability between alternative monotherapy and/or adjunctive therapy in these patients. A second ASM is often added, the efficacy of the combination is assessed, and the dose of the first drug can be gradually reduced and withdrawn. If seizures recur, the effective combination therapy can be reinstated. In this review, we discussed experimental and clinical data about the efficacy and tolerability of the most frequently used combinations of ASMs. Animal studies suggested that the most favorable combinations are those between ASMs with different or multiple mechanisms of action, whereas combining drugs with similar pharmacodynamic properties is often associated with additive or infra-additive efficacy and additive or synergistic toxicity. Clinical studies have shown that levetiracetam (LEV) can be favorably combined with the sodium channel blockers (SCBs) lacosamide (LCM) and lamotrigine (LTG). Lamotrigine is particularly effective when associated with valproate (VPA) and possibly with LEV and topiramate (TPM). Carbamazepine (CBZ) has negative pharmacokinetic interactions with several ASMs and should not be combined with other SCBs; it could be effectively and safely combined with gabapentin (GBP) and LEV. Valproic acid has enzyme inhibiting properties and can be cautiously used with SCBs; its combination with TPM or zonisamide (ZNS) may be associated with higher toxicity.

Perampanel effectiveness and tolerability in patients with epilepsy at long-term follow-up

INTRODUCTION

The main of the present study was to assess the effectiveness and tolerability of perampanel (PER) in association with 1 or 2 concomitant antiseizure medications (ASMs) in patients with epilepsy throughout a follow-up period of 24 months or longer in a real-world setting.

METHODS

This retrospective, observational, multi-center study collected data from both underage (<18 years old) and adult patients who had started PER in association with 1 or 2 ASMs. Only patients who had started PER and were followed up for at least 24 months were included. Response to treatment was analyzed at the 24-, 36-, and 48-month visits by considering the last visit undergone by patients. Subgroup analyses were performed according to age, gender, and epilepsy type and patients were categorized following PER treatment in concomitance with 1 or 2 ASMs to evaluate the factors affecting the achievement of seizure freedom (SF) at the 24-month FU.

RESULTS

Ninety-four patients were included (mean age 36.89 years; 51.1% female). At the 24-month follow-up visit, 90 (95.74%) patients were still receiving PER concomitantly with 1 or 2 ASMs. The mean PER dose was 6.02 mg/day and SF was achieved by 33 (35.1%) patients. A significantly higher SF rate was found in patients who had started PER with only 1 ASM when compared to those who had started PER with 2 concomitant ASMs. Effectiveness was maintained also in the subgroups of patients with a 36- or 48-month follow-up visit. Adult patients had a higher final daily dosage of PER than underage patients. Logistic regression found that the lowest number of previously failed ASMs was associated with a higher SF rate (p = 0.036).

CONCLUSION

Perampanel demonstrated a good effectiveness in association with 1 or 2 ASMs in both pediatric and adult patients, without having to use a high dose of the drug. The possibility to present SF was higher when PER was added early. Finally, the maintenance of effectiveness was observed also in the subgroups of patients with a follow-up of 36 and 48 months.

Efficacy of Home Anticonvulsant Administration for Second-Line Status Epilepticus Treatment

OBJECTIVE

To investigate whether receiving a second-line anticonvulsant medication that is part of a patient's home regimen influences outcomes in benzodiazepine-refractory convulsive status epilepticus.

METHODS

Using the Established Status Epilepticus Treatment Trial data, allocation to a study drug included in the patient's home anticonvulsant medication regimen was compared to receipt of an alternative second-line study medication. The primary outcome was cessation of clinical seizures with improved consciousness by 60 minutes after study drug initiation. Secondary outcomes were seizure cessation adjudicated from medical records and adverse events. We performed inverse probability of treatment-weighted (IPTW) logistic regressions.

RESULTS

Of 462 patients, 232 (50%) were taking 1-2 of the 3 study medications at home. The primary outcome was observed in 39/89 (44%) patients allocated to their home medication vs 76/143 (53%) allocated to a nonhome medication (IPTW odds ratio [OR] 0.66, 95% confidence interval [CI] 0.39-1.14). The adjudicated outcome occurred in 37/89 (42%) patients vs 82/143 (57%), respectively (IPTW OR 0.52, 95% CI 0.30-0.89). There was no interaction between study levetiracetam and home levetiracetam and there were no differences in adverse events.

CONCLUSION

There was no difference in the primary outcome for patients who received a home medication vs nonhome medication. However, the retrospective evaluation suggested an association between receiving a nonhome medication and seizure cessation.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that for patients with refractory convulsive status epilepticus, use of a home second-line anticonvulsant compared to a nonhome anticonvulsant did not significantly affect the probability of stopping seizures.

Real-world analysis of hospitalizations in patients with epilepsy and treated with perampanel

OBJECTIVES

(1) To evaluate risk of hospitalization following initiation of perampanel (pre- and post-analysis) and (2) to compare hospitalization rates following initiation of perampanel vs lacosamide.

METHODS

Patients were identified from Symphony Health's Patient Integrated Database if they had a prescription for perampanel (July 1, 2014-June 30, 2016). Patients 4-11 years of age with any partial-onset seizure (POS) or ≥12 years of age with any POS or primary generalized tonic-clonic seizure (GTCS) (pre-post); or ≥12 years of age (perampanel vs lacosamide). The first fill of perampanel ("index date") marked the start of the analysis period. Patients had ≥1 additional fill for perampanel and ≥2 diagnoses for epilepsy or nonfebrile convulsion diagnosis during pre-index (based on ICD-9/ICD-10 codes). Patients were matched using a 1:1 propensity scoring method for the perampanel vs lacosamide analysis. Primary outcome was hospitalization during the one year following medication initiation.

RESULTS

Pre- and post-perampanel: N = 1771 (mean age 34 years, 55% female). One-year all-cause hospitalization risk ratio was 0.76 (P < .05) and 36.2% with hospitalization during the pre-period vs 29.5% in the follow-up. One-year epilepsy-related inpatient hospitalization risk ratio was 0.72 (P < .05) and 30.8% with hospitalization during the pre-period vs 23.9% during follow-up. In the perampanel and lacosamide cohorts, N = 1717 per cohort after matching, most baseline demographics were balanced. A higher percentage of subjects were prescribed ≥3 anti-seizure medications for perampanel vs lacosamide (60.5% vs 57.7%, P < .001). The perampanel cohort had a 9.6% reduction in all-cause hospitalizations vs 5.8% for the lacosamide cohort (P < .05). Epilepsy-related hospitalizations decreased from the pre-index rate by 9.9% for perampanel and 8.3% for lacosamide (P < .05). Among those with baseline hospitalizations, perampanel was associated with a 59.9% reduction in all-cause hospitalizations vs 48.6% for lacosamide (P < .05), and for epilepsy-related hospitalizations, a reduction of 65.0% vs 58.9%, respectively (P < .05).

SIGNIFICANCE

Perampanel was associated with a significant reduction in one-year hospitalization risk.

The Pharmacoresistant Epilepsy: An Overview on Existant and New Emerging Therapies

Epilepsy is one of the most common neurological chronic disorders, with an estimated prevalence of 0. 5 – 1%. Currently, treatment options for epilepsy are predominantly based on the administration of symptomatic therapy. Most patients are able to achieve seizure freedom by the first two appropriate drug trials. Thus, patients who cannot reach a satisfactory response after that are defined as pharmacoresistant. However, despite the availability of more than 20 antiseizure medications (ASMs), about one-third of epilepsies remain drug-resistant. The heterogeneity of seizures and epilepsies, the coexistence of comorbidities, and the broad spectrum of efficacy, safety, and tolerability related to the ASMs, make the management of these patients actually challenging. In this review, we analyze the most relevant clinical and pathogenetic issues related to drug-resistant epilepsy, and then we discuss the current evidence about the use of available ASMs and the alternative non-pharmacological approaches.

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.

Evaluation of Factors Impacting the Efficacy of Single or Combination Therapies of Valproic Acid, Carbamazepine, and Oxcarbazepine: A Longitudinal Observation Study

Objective: This study aimed to determine the efficacy and clinical factors related to the pharmacodynamics of single or combination therapies of valproic acid (VPA), carbamazepine (CBZ), and oxcarbazepine (OXC), three commonly used anti-epileptic drugs (AEDs) in China.

Methods: The study evaluated the records of 2027 outpatients in a Changsha hospital, located in China, from December 23, 2015 to October 28, 2019. The baseline seizure frequency was assessed during the first visit. AED efficacy was determined based on the reduction in seizures from baseline at the subsequent visits. Multivariable ordinal regression analysis was used to determine the association between the clinical factors (demographic characteristics, clinical features, and medication situation) and AED efficacy. For validation, the clinical efficacies of AEDs were compared as both single agents and in combinations. Differences in adverse effect (AEs) categories were analyzed by Chi-square between AED groups.

Results: Records of patients receiving VPA, CBZ, and OXC were evaluated. Serum concentrations of VPA and CBZ is significantly correlated with efficacy (OR 1.030 [1.024–1.037], p < 0 0.0001; OR 1.250 [1.146–1.63], p < 0.0001, respectively) and OXC efficacy correlated to the serum concentration of the metabolite 10,11-dihydro-10-hydroxy-carbazepine (monohydroxy derivative, MHD) serum concentrations (OR 1.060 [1.031–1.089], p < 0.0001). Significant differences existed between females and males in VPA efficacy (OR 1.318 [1.033–1.682], p = 0.027). After validation, VPA, in combination with OXC (OR 1.93 [1.38–2.70], p<0.001), or with VGB (Vigabatrin) (OR 2.36 [1.38–2.70], p = 0.002), showed significantly better efficacy than as a single agent. OXC efficacy was also affected by the duration of epilepsy (OR 0.965 [0.946–0.984], p < 0.001). Additionally, the efficacies of OXC and VPA were also affected by the seizure type. Seizure reduction improved significantly with an increasing number of pharmacists’ educations in the first three visits period. There were no differences in AEs incidence among these 3 AEDs except for Psychiatric (0.02) and nervous system disorders (0.0001).

Conclusion: Serum concentrations of VPA and CBZ may positively affect their efficacies, while OXC efficacies are correlated to MHD serum concentrations. The efficacy of VPA was higher in females compared to males. VPA-OXC and VPA-VGB combinations had higher efficacies compared to monotherapy. Besides, OXC efficacy is probably reducing by the duration of epilepsy. Additionally, VPA efficacy for focal or generalized seizures is superior to mixed-type seizures. OXC was more effective for focal seizures compared to mixed-type ones. Education provided by pharmacists improved the seizures to some extent, and there were no significant differences between most categories of adverse effects for the investigated AEDs.

Efficacy and safety of eslicarbazepine acetate as a first or later adjunctive therapy in patients with focal seizures

INTRODUCTION

We report outcomes from an open-label, non-randomized, 24-week study of eslicarbazepine acetate (ESL) in adults at earlier and later stages of their treatment history for focal seizures, conducted in a real-world clinical setting.

METHODS

ESL was taken as the first adjunctive therapy to levetiracetam (LEV) or lamotrigine (LTG) monotherapy (Arm 1), or as a later adjunctive therapy in treatment-resistant patients (Arm 2). The primary objective was to evaluate the effectiveness of ESL (by retention rates). Secondary objectives were to evaluate efficacy (seizure frequency), safety, tolerability, behavioral changes, mood, and health-related quality of life (HRQoL) associated with ESL treatment.

RESULTS

The modified intent-to-treat population included 96 patients (Arm 1: n = 41; Arm 2: n = 55) and the safety population included 102 patients (Arm 1: n = 44; Arm 2: n = 58). Overall, 81.8 % of patients in Arm 1 and 63.8 % of patients in Arm 2 completed the 24-week maintenance period. Median reductions in standardized seizure frequency (SSF) were markedly higher in Arm 1 (72.8 %) than Arm 2 (22.8 %), as were responder rates (≥50 % reduction in SSF; Arm 1: 62.5 %; Arm 2: 38.5 %) and rates of seizure freedom (Arm 1: 25.0 %; Arm 2: 9.6 %). Efficacy outcomes were generally more favorable in patients taking ESL in combination with LEV versus other anti-seizure medications (ASMs). Treatment-emergent adverse events (TEAEs; 81 % vs 73 %) and TEAEs leading to discontinuation (16 % vs 2 %) were reported more frequently in Arm 2 than Arm 1, respectively. Serious adverse events were reported infrequently (Arm 1: 0; Arm 2: 7 %). The most common TEAEs were dizziness, nausea, headache, somnolence, fatigue, nasopharyngitis, vomiting, and anxiety. There were no notable changes in depressive symptoms, mood status, or aggression throughout the study. Health and HRQoL scores were generally high at baseline and did not change throughout the study. However, on average, both clinicians and patients perceived improvement in illness over the course of the study.

CONCLUSIONS

ESL was effective and well tolerated both as the first adjunctive therapy to either of the most prescribed first-line ASMs, LEV or LTG, and as a later adjunctive therapy in treatment-resistant patients.

Real-world hospitalization risk in patients with epilepsy treated with perampanel

AIM

The aim of this study was to evaluate the risk of hospitalization and emergency department admission following initiation of perampanel treatment in patients with epilepsy.

METHODS

This study is a retrospective longitudinal cohort study (Optum® Clinformatics® Datamart). Patients 4 to 11 years of age with a diagnosis of partial onset seizures or ≥12 years of age with primary generalized tonic-clonic seizures who had ≥1 perampanel prescription between 1/1/2014 and 3/31/2018 were eligible for the study. Additionally, patients were required to have 12-months of continuous enrollment before (pre-) and after (post-) the date of the first perampanel prescription (index-date). One-year relative-risks of all-cause and epilepsy-related hospitalizations and emergency department (ED) visits were estimated following initiation of perampanel treatment. Outcomes were also evaluated among a subsets of patients who were adherent to perampanel treatment, defined as a Medication Possession Ratio (MPR) ≥80%.

RESULTS

A total of 320 patients were included in the study, mean age 38.2 ± 19 years, 56.6% female. In the overall population, the relative risks of hospitalizations or ED visits after perampanel initiation were not significantly different. Among the 145 patients who had an MPR ≥80%, initiation of perampanel treatment resulted in a significantly lower risk of epilepsy-related hospitalization (relative risk [RR] = 0.68, confidence interval [CI] [0.47, 0.98]), all-cause ED visits (RR = 0.80, CI [0.66, 0.98]), and epilepsy-related ED visits (RR = 0.74, CI [0.57, 0.95]) in the follow-up period.

CONCLUSIONS

Adherence to perampanel treatment was associated with significant reductions in one-year hospitalizations and ED visit risk in real world settings.

Starting a new anti-seizure medication in drug-resistant epilepsy: Add-on or substitute?

OBJECTIVES

Randomized studies in drug-resistant epilepsy (DRE) typically involve addition of a new anti-seizure medication (ASM). However, in clinical practice, if the patient is already taking multiple ASMs, then substitution of one of the current ASMs commonly occurs, despite little evidence supporting this approach.

METHODS

Longitudinal prospective study of seizure outcome after commencing a previously untried ASM in patients with DRE. Multivariable time-to-event and logistic regression models were used to evaluate outcomes by whether the new ASM was introduced by addition or substitution.

RESULTS

A total of 816 ASM changes in 436 adult patients with DRE between 2010 and 2018 were analyzed. The new ASM was added on 407 (50.1%) occasions and substituted on 409 (49.9%). Mean patient follow-up was 3.2 years. Substitution was more likely if the new ASM was enzyme-inducing or in patients with a greater number of concurrent ASMs. ASM add-on was more likely if a γ-aminobutyric acid (GABA) agonist was introduced or if the patient had previously trialed a higher number of ASMs. The rate of discontinuation due to lack of tolerability was similar between the add-on and substitution groups. No difference between the add-on and substitution ASM introduction strategies was observed for the primary outcome of ≥50% seizure reduction at 12 months.

SIGNIFICANCE

Adding or substituting a new ASM in DRE has the same influence on seizure outcomes. The findings confirm that ASM alterations in DRE can be individualized according to concurrent ASM therapy and patient characteristics.

Epilepsy: Workup and Management in Adults

When managing epilepsy, there is a temptation to focus care with respect to the last and the next seizure. However, epilepsy is a multifaceted chronic condition and should be treated as such. Epilepsy comes with many physical risks, psychological effects, and socioeconomic ramifications, demanding a long-term commitment from the treating physician. Patients with epilepsy, compared to other chronically ill patient populations, have a worse quality of life, family function, and less social support. The majority of patients are well controlled on antiseizure drugs. However, approximately one-third will continue to have seizures despite optimized medical management. The primary aim of this article is to explore the long-term management of chronic epilepsy, and to address some of the particular needs of patients with chronic epilepsy.

Is the mechanism of action of antiseizure drugs a key element in the choice of treatment?

About 25 antiseizure drugs are available for the treatment of patients with epilepsy. The choice of the most suited drug for a specific patient is primarily based on the results of the pivotal randomized clinical trials and on the patient's characteristics and comorbidities. Whether or not the mechanism of action of the antiseizure drugs should be also taken into account to better predict the patient's response to the treatment remains a matter of debate. Despite the apparent complexity and diversity of antiseizure drug mechanisms of action, the reality unfortunately remains that they are very close, in particular with regard to their relationship with the pathophysiology of epilepsy. With the only exception of the association between lamotrigine and sodium valproate, there are no clinical data that formally support a synergistic association between certain antiseizure drugs in terms of efficacy. However, anticipating risk of adverse events by limiting as far as possible the combination of drugs, which share the same mechanisms of action, is undoubtedly an important driver of daily therapeutic decisions.

Evaluation of adverse drug reaction profile of antiepileptic drugs in persons with epilepsy: A cross-sectional study

INTRODUCTION

Newer antiepileptic drugs (AEDs) are preferred over conventional AEDs with the perception of better safety profile and efficacy though there is a lack of confirmatory evidence. The present study assessed the adverse drug reactions' (ADRs) profile of AEDs prescribed in persons with epilepsy (PWE) as per the System Organ Class (SOC) and compared them on the basis of demographics and treatment pattern.

MATERIAL AND METHODS

This prospective, cross-sectional, and observational study was conducted in PWE attending Neurology Outpatient-Department from February 2016 to April 2019 who were presented with any ADR. World Health Organization-Uppsala Monitoring Centre (WHO-UMC) scale was used for the causality assessment of suspected ADRs.

RESULTS

Among the 1011 PWE on AEDs, male:female ratio was 622:389, adult:pediatric ratio 736:275, and conventional:newer AEDs ratio 624:387. Among monotherapy PWE (47.1%), commonly used AEDs were levetiracetam (34.4%), valproic acid (22.9%), carbamazepine (18.3%), phenytoin (11.9%), and other AEDs (12.5%). A total of 1990 ADRs (1.96 ADRs per PWE) were reported as per SOC; among them, newer vs. conventional AEDs did not reveal any significant difference; however, monotherapy vs. polytherapy showed differences in nervous system disorders (p = 0.01) and skin and subcutaneous tissue disorders (p = 0.005). Causality assessment revealed 0.3% certain, 27.3% probable, 61.3% possible, and 11.1% unlikely association of ADRs with AEDs. Depending on the ADRs, there was either withdrawal of AED (0.9%), reduction in dose (48.4%), or continuation in the same dose as before (50.7%).

CONCLUSION

The ADR analysis showed that newer AEDs were associated with a similar trend of ADRs as that of conventional AEDs. Thus, the choice among newer and conventional AEDs should preferably focus on the experience of better efficacy in addition to safety data.

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.

Avoiding complacency when treating uncontrolled seizures: why and how?

Introduction: Despite the advances in the diagnosis and treatment of epilepsy, approximately 30% of the patients remain intractable. Uncontrolled seizures have deleterious consequences, including brain damage, cognitive decline, decreased quality of life, and increased mortality.Areas covered: In this article, the authors discuss the treatment gap in patients with intractable epilepsy and the possible mechanisms of drug resistance. The authors provide a treatment algorithm for patients with intractable epilepsy, including non-pharmacological treatment options, such as diet, neurostimulation (vagus nerve stimulation, responsive neurostimulation, and deep brain stimulation), curative surgeries, and palliative surgeries.Expert opinion: There are currently several gaps in the management of seizures. Thirty percent of the 1% of the population with epilepsy is drug resistant. Non-pharmacologic treatments have improved in the last 30 years and continue to do so, but epilepsy surgery in general is still vastly under-utilized. Resective surgery is the only potentially curative procedure. Neurostimulation is generally palliative and is also improving, with smarter types of neurostimulation and paradigms.

The role of polytherapy in the management of epilepsy: suggestions for rational antiepileptic drug selection

Introduction: Antiepileptic polytherapy may be indicated in patients experiencing drug-resistant epilepsy. To date, there are no evidence-based criteria on how to combine different antiepileptic drugs (AEDs) together, in order to obtain the best therapeutic response.Areas covered: This paper reviews the available data about the various associations of AEDs in patients undergoing polytherapy, focusing on the most effective and well-tolerated polytherapies. Moreover, some controversial aspects of this topic are addressed.Expert opinion: Nowadays, there are no guidelines on polytherapy in patients with epilepsy; thus, the management of pharmacoresistant epilepsy is still uncertain, except for valproate/lamotrigine combination, which seems to be the only one recommended. Data regarding mechanism of action, pharmacokinetics, tolerability, and, more importantly, the analysis of the valuable clinical studies of drug combinations can help physicians to choose the best and most effective AED association for each patient.

Update on Antiepileptic Drugs 2019

PURPOSE OF REVIEW

This article is an update from the article on antiepileptic drug (AED) therapy published in the last Continuum issue on epilepsy and is intended to cover the vast majority of agents currently available to the neurologist in the management of patients with epilepsy. Treatment of epilepsy starts with AED monotherapy. Knowledge of the spectrum of efficacy, clinical pharmacology, and modes of use for individual AEDs is essential for optimal treatment for epilepsy. This article addresses AEDs individually, focusing on key pharmacokinetic characteristics, indications, and modes of use.

RECENT FINDINGS

Since the previous version of this article was published, three new AEDs, brivaracetam, cannabidiol, and stiripentol, have been approved by the US Food and Drug Administration (FDA), and ezogabine was removed from the market because of decreased use as a result of bluish skin pigmentation and concern over potential retinal toxicity.Older AEDs are effective but have tolerability and pharmacokinetic disadvantages. Several newer AEDs have undergone comparative trials demonstrating efficacy equal to and tolerability at least equal to or better than older AEDs as first-line therapy. The list includes lamotrigine, oxcarbazepine, levetiracetam, topiramate, zonisamide, and lacosamide. Pregabalin was found to be less effective than lamotrigine. Lacosamide, pregabalin, and eslicarbazepine have undergone successful trials of conversion to monotherapy. Other newer AEDs with a variety of mechanisms of action are suitable for adjunctive therapy. Most recently, the FDA adopted a policy that a drug's efficacy as adjunctive therapy in adults can be extrapolated to efficacy in monotherapy. In addition, efficacy in adults can be extrapolated for efficacy in children 4 years of age and older. Both extrapolations require data demonstrating that an AED has equivalent pharmacokinetics between its original approved use and its extrapolated use. In addition, the safety of the drug in pediatric patients has to be demonstrated in clinical studies that can be open label. Rational AED combinations should avoid AEDs with unfavorable pharmacokinetic interactions or pharmacodynamic interactions related to mechanism of action.

SUMMARY

Knowledge of AED pharmacokinetics, efficacy, and tolerability profiles facilitates the choice of appropriate AED therapy for patients with epilepsy.

New-onset lesional and nonlesional epilepsy in the US population: Patient characteristics and patterns of antiepileptic drug use

PURPOSE

Describe treatment patterns in patients from the United States with new-onset epilepsy, comparing those with and without lesional epilepsy.

METHODS

In this observational study we used Truven Health MarketScan databases derived from commercial health insurance, Medicare and Medicaid claims covering at least 5 years, commencing in 2008. We identified incident epilepsy cases based on International Classification of Diseases, Ninth Revision, Clinical Modification codes indicating epilepsy or recurrent seizures, taking into account antiepileptic drug (AED) claims, consistent with International League Against Epilepsy Commission on Epidemiology recommendations. We identified patients with lesional epilepsy when associated diagnoses indicated central nervous system infection, neoplasm, traumatic brain injury, stroke, senile dementia and static encephalopathy. Lesional and nonlesional cohorts were matched 1:1 on baseline characteristics of age, sex and insurance type for group comparisons.

RESULTS

In unmatched cohorts lesional epilepsy patients (N = 15,302) were more commonly older (mean age 48.7 years) compared with nonlesional epilepsy patients (N = 15,970; mean age 18.5 years). Among lesional patients <20 years of age, the leading putative etiology was static encephalopathy, while among ages ≥20 years and older, the leading putative etiology was stroke or cerebrovascular disease. In matched cohorts (7063 patients each), those with lesional epilepsy were significantly less likely to be untreated at 1 year versus those with nonlesional epilepsy (37.2% vs 56.1%). In children and adults among matched cohorts, levetiracetam was the most common AED prescribed for initial AED therapy for the lesional (39.5%) and nonlesional (32.1%) groups. Lesional epilepsy patients on monotherapy were only slightly less likely than nonlesional epilepsy patients to be on the same AED 1 year after treatment initiation (55.6% vs 59.7%).

SIGNIFICANCE

Compared with patients with lesional epilepsy, a higher proportion of patients with nonlesional epilepsy remain untreated 1 year after diagnosis. There were differences in AED selection by epilepsy etiology; levetiracetam is the most commonly prescribed drug for both cohorts.

Clinical opinion: Earlier employment of polytherapy in sequential pharmacotherapy of epilepsy

Modern pharmacotherapy for epilepsy consists of orderly, sequential drug trials, in which antiepileptic drugs (AEDs) are chosen under the concept of individual patient-oriented (or - tailored) pharmacotherapy. Although monotherapy has been established as the preferred mode of AEDs therapy in both newly diagnosed and drug resistant epilepsies, there are still lack of evidence to favor either monotherapy or polytherapy in epilepsy, which has generated continuing controversies on the preferred mode of pharmacotherapy. However, each mode of pharmacotherapy may have both advantages and disadvantages, which are different and variable related to individual case scenario. We conducted a brief comparative overview between monotherapy and polytherapy to provide clues for earlier employment of polytherapy in each steps of sequential drug trials. Previous claims about the advantages of monotherapy over polytherapy are not supported but gradually losing its ground by the introduction of a large number of drugs carrying pharmacological advantages for combination therapy. Current evidence stresses the importance of combining drugs having synergistic interactions for better outcome of polytherapy, which has not been considered in previous clinical investigations comparing monotherapy and polytherapy. It is likely that a significant improvement in the outcome of current AEDs therapy is feasible by earlier employment of polytherapy as well as identification of combination drug regimens carrying synergistic interactions. At present, lamotrigine(LTG) and valproate(VPA) combination regimen is the only well documented synergistic regimen, but there are a long-list of candidate regimens requiring future trials in appropriate designs.

Antiepileptic Drug Therapy in Patients with Drug-Resistant Epilepsy

Antiepileptic drug (AED) therapy starts with an accurate diagnosis of epilepsy and is followed by sequential drug trials. Seizure freedom is largely achieved by the first two drug trials; thus, epilepsy that cannot be controlled after appropriately conducted trials of the first two drugs is defined as drug-resistant epilepsy (DRE). It is still unclear which mode of pharmacotherapy, among monotherapy and polytherapy, shows better outcomes in cases of DRE. However, in a recent large hospital cohort study over past two decades, combination therapy was associated with a progressive increase in seizure-free rate than monotherapy in DRE. The benefits of polytherapy in the management of DRE might be related to the recent introduction of many new AEDs with different and novel mechanisms of action and better pharmacokinetic and tolerability profiles. These new AEDs were introduced to the market after they have proven their superiority over placebos in randomized controlled trials (RCTs) on add-on therapy in patients with DRE. Therefore, polytherapy including these new AEDs in the regimen is the approved mode of treatment for cases of DRE; this has prompted physicians to try various combinations of polytherapy to optimize the clinical outcomes. In addition, the significant discrepancies in AED responder rates between RCTs and real-world practice may support the importance of judicious use of new drugs in polytherapy by experienced epileptologists. Most experts now agree to the concept of “rational polytherapy” consisting of mechanistic combinations of AEDs exerting synergistic interactions and to the importance of continuing trials of different rational polytherapy regimens to improve the outcome of the core population of epilepsy patients in the long term.