Eslicarbazepine acetate as adjunctive therapy in patients with uncontrolled partial-onset seizures: Results of a phase III, double-blind, randomized, placebo-controlled trial

Efficacy and safety of add-on antiseizure medications for focal epilepsy: A network meta-analysis

OBJECTIVE

Several antiseizure medications (ASMs) have been approved for the treatment of focal epilepsy. However, there is a paucity of evidence on direct comparison of ASMs. We evaluated the comparative efficacy and safety of all approved add-on ASMs for the treatment of focal epilepsy using network meta-analysis.

METHODS

Data through extensive literature search was retrieved from PubMed, Embase, Cochrane, and ClinicalTrial.gov databases using predefined search terms from inception through March 2023. PRISMA reporting guidelines (CRD42023403450) were followed in this study. Efficacy outcomes assessed were ≥50%, ≥75%, and 100% responder rates. Patient retention rate and safety outcomes such as overall treatment-emergent adverse events (TEAEs) and individual TEAEs were assessed. "Gemtc" 4.0.4 package was used to perform Bayesian analysis. Outcomes are reported as relative risks (RRs) and 95% confidence interval (CI).

RESULTS

Literature search retrieved 5807 studies of which, 75 studies were included in the analysis. All ASMs showed significantly higher ≥50% responder rate compared with placebo. Except the ≥75% seizure frequency reduction for zonisamide (2.23; 95% CI: 1.00-5.70) and 100% for rufinamide (2.03; 95% CI: 0.54-11.00), all other interventions showed significantly higher ≥75% and 100% responder rates compared with placebo. Among treatments, significantly higher 100% responder rate was observed with cenobamate compared to eslicarbazepine (10.71; 95% CI: 1.56-323.9) and zonisamide (10.63; 95% CI: 1.37-261.2). All ASMs showed a lower patient retention rate compared to placebo, with the least significant value observed for oxcarbazepine (0.77; 95% CI: 0.7-0.84). Levetiracetam showed a lower risk of incidence (1.0; 95%CI: 0.94-1.1; SUCRA: 0.885067) for overall TEAE compared with other medications.

SIGNIFICANCE

All approved ASMs were effective as add-on treatment for focal epilepsy. Of the ASMs included, cenobamate had the greatest likelihood of allowing patients to attain seizure freedom.

PLAIN LANGUAGE SUMMARY

This article compares the efficacy and safety of antiseizure medications (ASMs) currently available to neurologists in the treatment of epileptic patients. Several newer generation ASMs that have been developed may be as effective or better than the older medications. We included 75 studies in the analysis. In comparison, all drugs improved ≥50%, ≥75% and 100% responder rates compared to control, except for Zonisamide and Rufinamide in the ≥75% and 100% responder rate categories. Retention of patients undergoing treatment was lower in drugs than placebo. All drugs were tolerated, the levetiracetam showed the best tolerability. Cenobamate more likely help completely to reduce seizures.

Assessing the Effectiveness of Eslicarbazepine Acetate in Reducing Audiogenic Reflex Seizures in the GASH/Sal Model of Epilepsy

Eslicarbazepine acetate (ESL) is a third-generation antiepileptic drug indicated as monotherapy for adults with newly diagnosed epilepsy and as adjunctive therapy for the treatment of partial seizures. Our aim was to assess the effectiveness and safety of both acute and repeated ESL administration against reflex audiogenic seizures, as shown by the Genetic Audiogenic Seizures Hamster from Salamanca (GASH/Sal). Animals were subject to the intraperitoneal administration of ESL, applying doses of 100, 150 and 200 mg/kg for the acute study, whereas a daily dose of 100 mg/kg was selected for the subchronic study, which lasted 14 days. In both studies, the anticonvulsant effect of the therapy was evaluated using neuroethological methods. To assess the safety of the treatment, behavioral tests were performed, hematological and biochemical liver profiles were obtained, and body weight was monitored. In addition, the ESL levels in blood were measured after the acute administration of a 200 mg/kg dose. Treatment with ESL caused a reduction in seizure severity. No statistically significant differences were detected between the selected doses or between the acute or repeated administration of the drug. To summarize, the intraperitoneal administration of ESL is safe and shows an anticonvulsant effect in the GASH/Sal.

Long-term effects of adjunctive eslicarbazepine acetate in adult Asian patients with refractory focal seizures: Post hoc analysis of a phase III trial

A post hoc analysis of data from Asian patients included in the study BIA-2093-304 was conducted to evaluate the long-term safety/tolerability and efficacy of adjunctive eslicarbazepine acetate (ESL) in adult Asian patients with refractory focal seizures. Part I was a randomized controlled trial, in which patients received ESL (800 or 1200 mg once daily [QD]) or placebo, assessed over a 12-week maintenance period. Patients completing Part I could enter two open-label extension periods (Part II, 1 year; Part III, ≥2 years), during which all received ESL (400-1600 mg QD). Safety/tolerability was assessed by evaluating treatment-emergent adverse events (TEAEs). Efficacy assessments included responder and seizure freedom rates. The safety population included 125, 92, and 23 Asian patients in Parts I, II, and III, respectively. Incidence of ESL-related TEAEs was 61.3%, 45.7%, and 17.4% during Parts I, II, and III, respectively. ESL-related TEAEs (most commonly, dizziness, somnolence, and headache) were consistent with ESL's known safety profile. During Part I, responder rates were higher with ESL 800 (41.7%) and 1200 mg QD (44.4%) versus placebo (32.6%), although not statistically significant. Seizure freedom rates with ESL 800 (5.5%) and 1200 mg QD (11.1%) were also higher versus placebo (0%) (p < 0.05 for ESL 1200 mg QD versus placebo). At the end of Part II, responder and seizure freedom rates were 60.3% and 14.7%, respectively. In summary, adult Asian patients with refractory focal seizures were responsive to treatment with ESL as adjunctive therapy and generally showed treatment tolerance well for up to 3 years. No new/unexpected safety findings were observed.

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.

Efficacy, tolerability and safety of add-on third-generation antiseizure medications in treating focal seizures worldwide: a network meta-analysis of randomised, placebo-controlled trials

Background

Adjunctive newer antiseizure medications (ASMs) are being used in patients with treatment-resistant focal-onset seizures (FOS). An updated network meta-analysis (NMA) was necessary to compile evidence in this critical area.

Methods

We systematically searched PubMed, Embase, Cochrane Library, Web of Science, and Scopus from their inception until 17 January 2024, evaluating the efficacy, tolerability, and safety of rufinamide (RUF), brivaracetam (BRV), cenobamate (CNB), eslicarbazepine (ESL), lacosamide (LCM), retigabine (RTG), and perampanel (PER) as adjunctive treatments for FOS. Efficacy outcomes included seizure response and seizure freedom. Tolerability was assessed by discontinuation due to adverse events (AEs). Safety outcomes were evaluated based on the number of patients experiencing at least one AE and serious adverse events (SAEs). This review is registered with PROSPERO (CRD42023485130).

Findings

A total of 29 studies involving 11,750 participants were included. For seizure response, all ASMs were significantly superior to placebo, with RTG ranking highest, followed by CNB. Considering dosage, CNB 400 mg/d was top-ranked, followed by RTG 1200 mg/d. For seizure freedom, BRV was highest-ranked, followed by CNB, with BRV 100 mg/d leading, followed by CNB 400 mg/d. Regarding tolerability, LCM 600 mg/d had the lowest ranking, followed by CNB 400 mg/d. For the safety outcome of AEs, ESL 1200 mg/d was ranked lowest, followed by CNB 400 mg/d. Regarding SAEs, LCM 400 mg/d was ranked lowest, followed by RTG 1200 mg/d.

Interpretation

ASMs at different dosages have varying efficacy and tolerability profiles. We have provided hierarchical rankings of ASMs for efficacy and safety outcomes. Our findings offer the most comprehensive evidence available to inform patients, families, physicians, guideline developers, and policymakers about the choice of ASMs in patients with treatment-resistant FOS.

Funding

None.

Efficacy, safety, and tolerability of adjunctive eslicarbazepine acetate in patients with focal to bilateral tonic-clonic seizures

OBJECTIVE

To report the efficacy, safety, and tolerability of adjunctive eslicarbazepine acetate (ESL) treatment in reducing focal to bilateral tonic-clonic seizures (FBTCS).

METHODS

Data were pooled from 3 randomized clinical trials (RCTs) of adjunctive ESL in patients with focal seizures. Patients treated with 800 or 1200 mg/day ESL and who experienced ≥ 1 FBTCS during baseline were included. Efficacy was measured using FBTCS standardized seizure frequency (SSF), responder rates (≥50%, ≥75%, and 100%), and time to first FBTCS. Adverse events (AEs) were tabulated for each subgroup.

RESULTS

Of the original 1447 patients, 438 patients in the safety population were included with ≥ 1 FBTCS at baseline (efficacy population, n = 429). Patients with ≥ 2 FBTCS (safety, n = 354; efficacy, n = 346) and ≥ 3 FBTCS (safety, n = 294; efficacy, n = 288) at baseline were also analyzed. The 1200 mg/day ESL group experienced lower least squares mean SSF vs placebo in patients with ≥ 1 baseline FBTCS (P = 0.0395) and ≥ 3 baseline FBTCS (P = 0.0091). The 50% responder rates improved for 1200 mg/day ESL vs placebo (≥1 FBTCS, P = 0.005; ≥2 FBTCS, P = 0.0063; ≥3 FBTCS, P = 0.0016). The 75% responder rates improved with 1200 mg/day ESL vs placebo (≥1 FBTCS, P = 0.0315; ≥2 FBTCS, P = 0.0215; ≥3 FBTCS, P = 0.0099), and with 800 mg/day ESL for ≥ 2 FBTCS at baseline (P = 0.0486). The 100% responder rate was higher in patients treated with 1200 mg/day ESL (not significant). Time to first FBTCS was longer with both 800 (P = 0.0008) and 1200 mg/day (P = 0.0020) ESL vs placebo for the ≥ 1 FBTCS subgroup, and with 1200 mg/day ESL for ≥ 2 FBTCS (P = 0.0060) and ≥ 3 FBTCS (P = 0.0152) subgroups. Overall, AEs occurred at similar rates across subgroups, and were lower than the original RCTs.

CONCLUSION

Adjunctive ESL produced a robust response in patients with FBTCS, a seizure type associated with SUDEP and high injury rates. Adjunctive ESL was well tolerated in patients who experienced FBTCS.

Eslicarbazepine-induced hyponatremia: A retrospective single-center real clinical practice study

Hyponatremia is a typical side effect of antiseizure drugs from the dibenzazepine family. The study investigated the prevalence of hyponatremia in patients with epilepsy who were treated with eslicarbazepine. We aimed to determine the prevalence of hyponatremia, reveal the factors leading to the discontinuation of treatment, and identify possible risk factors for the development of hyponatremia including the dose dependency. The medical records of 164 patients with epilepsy taking eslicarbazepine in our center were analyzed. The overall prevalence of hyponatremia was 30.5%. The prevalence of mild hyponatremia, seen in 14%-20% of patients, was not dose dependent. The prevalence of moderate and severe hyponatremia was significantly dose dependent. The severity of hyponatremia was significantly dose dependent. Severe hyponatremia was found in 6.1% of patients. Hyponatremia was asymptomatic in the majority of cases, and in 48% did not require any management. Hyponatremia was the reason for discontinuation in 6.2% of patients. The major risk factor for developing hyponatremia was older age. The study shows that eslicarbazepine-induced hyponatremia is usually mild and asymptomatic. It usually does not require any management and seldom leads to treatment discontinuation. Hyponatremia is dose dependent. Another major risk for developing hyponatremia (besides dose) is older age.

Thirteen years of experience with eslicarbazepine acetate in the United Kingdom and Republic of Ireland: A safety perspective

OBJECTIVE

Eslicarbazepine acetate (ESL) is a once-daily oral antiseizure medication. Its safety and tolerability from clinical trials have been mostly confirmed by real-world data. The main purpose of this report is to provide an overview of the safety profile of ESL in the United Kingdom (UK) and Republic of Ireland (ROI).

METHODS

Safety data were obtained from the UK and ROI post-marketing sources (October 2009-April 2022) by the marketing authorization holder. All individual reports were included in the Argus Safety™ database. All adverse events (AEs) were coded using MedDRA® version 24.1. Only valid cases (meeting the minimum pharmacovigilance reporting requirements) were included.

RESULTS

During 13 years of ESL marketing, with cumulative estimated exposure of 2 210 395 patients-years, 183 reports were received. A total of 402 AEs were reported for the 155 valid reports. The most common reported AEs (≥6% of total reported), per system organ class (SOC), were: nervous system disorders (23.4%), injury, poisoning, and procedural complications (18.9%), general disorders and administration site conditions (12.9%), psychiatric disorders (12.7%) and gastrointestinal disorders (6.7%). The most frequently reported (≥2% of total reported) AEs were: seizure (4.5%), hyponatremia (4.2%), dizziness (2.7%), rash, fatigue (2.5% each), and somnolence (2.0%). Twenty-six percent of events were classified as serious (including six fatal cases).

SIGNIFICANCE

The current analysis supports the known safety profile of ESL, as generally well-tolerated with most AEs being non-serious. The most common AEs were considered either expected according to the disease itself or to the reference safety information. ESL continues to be a relevant medication in the treatment of partial (focal-onset) epilepsy, as also confirmed by the 2022 NICE guidelines.

Time to sustained responder status in patients with focal seizures treated with adjunctive eslicarbazepine acetate

Rapid and sustained clinical responses are critical in improving long-term outcomes in epilepsy. While a 50 % reduction from baseline in standardized seizure frequency (SSF) is often cited as a measure of clinically meaningful efficacy, sustained response (SR) is an alternative method that allows the assessment of onset and durability of the response. Time to sustained response in SSF of ≥ 50 %, ≥ 75 %, ≥ 90 %, and 100 % was assessed for pooled data from 3 similar randomized clinical trials of adjunctive eslicarbazepine acetate (ESL). Patients with focal seizures on stable doses of 1-2 antiseizure medications were randomized to placebo, ESL 800 mg/day, or ESL 1200 mg/day. SR50, SR75, SR90, and SR100 were defined as a ≥ 50 %, ≥ 75 %, ≥ 90 %, and 100 % reduction, respectively, in SSF compared to baseline occurring anytime during the 12-week maintenance period, sustained through the end of the maintenance period. Safety signals were assessed for patients with SR50 onset within the first 2 weeks of the maintenance period (early responders) and any point following the first 2 weeks (later responders). A total of 1221 patients were included in this analysis. SR50 was achieved as early as Day 1 (placebo, 4.7 %; ESL 800 mg/day, 8.8 %; ESL 1200 mg/day, 10.4 %). After 84 days, SR50 was achieved by 32.1 % of the placebo group, 46.9 % of the ESL 800 mg/day group (p = 0.0002 vs placebo), and 53.7 % of the ESL 1200 mg/day group (p < 0.0001 vs placebo). Both ESL groups demonstrated earlier SR50 onset compared with placebo (p < 0.0001). Time to SR50 onset was not statistically different between the 800 and 1200 mg/day ESL dose groups. SR75 (p = 0.0001), SR90 (p = 0.0019), and SR100 (p = 0.0014) were achieved significantly earlier in the ESL 1200 mg/day groups vs placebo. SR75 was achieved significantly earlier in the ESL 800 mg/day group vs placebo (p = 0.0188), while achievements of SR90 (p = 0.0525) and SR100 (p = 0.0540) trended toward earlier occurrence. A greater proportion of patients in the ESL groups compared to the placebo group achieved an SR50 during the maintenance period, and those patients in the ESL groups also achieved SR50 and SR75 sooner than placebo treated patients. Additionally, patients treated with the higher ESL dose achieved SR90 and SR100 sooner than those treated with placebo.

Long-term quality of life in patients with focal seizures treated with adjunctive eslicarbazepine acetate

By controlling seizures, anti-seizure medications can improve health-related quality of life (HRQOL). Data from a post-hoc pooled analysis of adjunctive eslicarbazepine acetate (ESL) was used to describe HRQOL measures, including overall quality of life, seizure worry, emotional well-being, energy/fatigue, cognitive functioning, medication effects, social function, and overall score over a period of up to one year. Patients who completed a double-blind treatment phase (Part 1) of these trials were eligible to enter the open label extension (OLE; Part 2). Patients who continued into the OLE initiated adjunctive ESL at 800 mg/day for 1 month before investigators could titrate dosages based on efficacy and tolerability. HRQOL was measured at baseline and at the last assessment using the Quality of Life in Epilepsy Inventory (QOLIE-31) in all patients who entered the 1-year OLE and in patients who completed the 1-year OLE. The mean QOLIE-31 scores and mean change in scores were analyzed using paired t-tests. The percentage of patients with improvements in QOLIE-31 scores beyond the minimally important change (MIC) threshold from baseline to end of 1-year OLE is described. Of 1410 patients in the intent-to-treat population, 1120 patients continued to part 2, and 795 patients completed the OLE. In patients who entered the OLE, mean improvements in scores for seizure worry, overall quality of life, emotional well-being, medication side effects, social functioning, and total score were statistically significant. In patients who completed the OLE, the mean change to final assessment was statistically significantly improved for all QOLIE categories. In patients who entered the OLE with a final assessment, the percentage of patients meeting the MIC for social functioning was the highest (46.9%), followed by medication effects (44.9%), and seizure worry (42.9%). Patients who completed the OLE with a final assessment found a similar rank ordering in QOLIE scale improvements compared with those who entered the OLE with a final assessment. For both sets of patient groups, the least number of subjects met MIC criteria for the energy/fatigue QOLIE category. Treatment with therapeutic doses of adjunctive ESL in patients with focal seizures was associated with improvements in HRQOL for a period of up to one year.

Psychiatric adverse events in three phase III trials of eslicarbazepine acetate for focal seizures

OBJECTIVE

Eslicarbazepine acetate (ESL) is a once-daily (QD), oral anti-seizure medication for the treatment of focal (partial-onset) seizures. Here, we evaluate risk factors for the development of psychiatric treatment-emergent adverse events (TEAEs) in clinical trials of adjunctive ESL in adults with focal seizures.

METHODS

This post-hoc analysis evaluated data pooled from three Phase III, randomized, double-blind, placebo-controlled trials (BIA-2093-301, -302, -304). After an 8-week baseline period, patients were randomized equally to receive placebo, ESL 400 mg (not reported here), 800 mg, or 1200 mg QD (up to 2-week titration; 12-week maintenance; optional open-label extension [OLE]). Incidences of psychiatric TEAEs were evaluated according to three separate criteria: medical history of psychiatric disorders (yes/no); baseline use of psychotropic drugs (yes/no); Montgomery-Åsberg Depression Rating Scale (MADRS) score at baseline (0-6: normal; 7-19: mild depression; 20-34: moderate depression).

RESULTS

The analysis populations comprised 1251 patients for the controlled study period and 1137 patients for the 1-year OLE. Psychiatric TEAE incidence was similar between patients taking ESL and placebo in the controlled and OLE study periods and was not related to ESL dose. Psychiatric TEAEs generally occurred more frequently in patients with a medical history of psychiatric disorders, using psychotropic drugs, or with depressive symptoms than in those without a history, not using psychotropic drugs, or with no depressive symptoms. Depression and anxiety were the most frequently reported psychiatric TEAEs.

SIGNIFICANCE

Overall, in clinical trials of ESL in adults with focal seizures, incidences of psychiatric events were not statistically different between patients taking ESL and placebo, were not related to ESL dose, and generally occurred more frequently in patients with baseline psychiatric symptoms or a history of psychiatric disorders. Long-term exposure to ESL was not associated with a marked increase in the incidence of psychiatric TEAEs.

The pharmacokinetic, safety, and tolerability profiles of eslicarbazepine acetate are comparable between Korean and White subjects

Eslicarbazepine acetate (ESL) is a prodrug antiseizure medication for the treatment of focal seizures. ESL shows a well-established pharmacokinetic (PK)-pharmacodynamic relationship and has similar extrinsic epilepsy-related factors across ethnicities. This study evaluated and compared ESL safety, tolerability, and PK characteristics between Korean and White subjects. A randomized, double-blind, placebo-controlled, single- and multiple-dose escalation study was conducted in healthy Korean and White adults. Participants randomly received a single dose and multiple oral doses of ESL (400-1600 mg) or placebo once daily for 11 days at a ratio of 8:2. Serial blood samples were collected to determine the plasma concentration of ESL and its metabolites (eslicarbazepine, [R-licarbazepine and oxcarbazepine). Safety and tolerability were assessed throughout the study. A total of 29 Korean and 20 White subjects completed the study. The PK profiles of the metabolites of ESL were similar between Korean and White subjects. The geometric mean ratio (90% confidence interval) of Korean to White subjects for the area under the concentration-time curve within a dosing interval of eslicarbazepine was 1.06 (0.97-1.17) and 0.96 (0.87-1.06) after multiple oral doses of 400 and 1600 mg ESL, respectively. Other PK parameters were also similar between the two ethnic groups. ESL was well-tolerated in healthy Korean and White subjects, and its PK characteristics were similar between the two ethnic groups. The results of this study support to use the same dosage regimen of ESL in both White and Korean patients with seizures.

Adjunctive Treatment With Eslicarbazepine Acetate for Adults and Children With Focal-Onset Epilepsy: A Meta-Analysis

Background

The efficacy and tolerability of eslicarbazepine acetate (ESL) in adults and children with focal-onset epilepsy (FOE) according to the dose remain to be validated. A meta-analysis based on randomized controlled trials (RCTs) was therefore conducted as a summary.

Methods

Relevant RCTs were collected by systematic searching the electronic databases of PubMed, Cochrane's Library, Embase, Wanfang and CNKI from inception to May 16, 2022. The random-effect model was adopted to pool the results by incorporating the possible heterogeneity. Efficacy outcomes including responsive rate and effective rate, defined as cases with 50 and ≥75% reduction in seizure frequency compared to baseline, were determined, respectively. Incidence of severe adverse events (AE) leading to drug discontinuation was also evaluated.

Results

Ten studies including 2,565 people with epilepsy contributed to the meta-analysis. For adults, ESL 400 mg/d did not improve the response rate or the effective rate; ESL 800 mg/d was associated with improved response rate (odds ratio [OR] 2.16, 95% confidence interval [CI]: 1.65-2.83, p < 0.001) and effective rate (OR 2.16, 95% CI: 1.41-3.30, p < 0.001) without significantly increased severe AE (OR 1.58, 95% CI: 0.90-2.78, p = 0.11); ESL 1,200 mg/d improved response rate (OR 2.49, p < 0.001) and effective rate (OR 3.09, p = 0.04), but significantly increased severe AE (OR 3.72, p < 0.001). For children, ESL also did not significantly improve the response rate (OR 1.76, p = 0.22) or the effective rate (OR 2.17, p = 0.13).

Conclusion

ESL 800 mg/d is effective and well-tolerated as adjuvants for adults with FOE. Efficacy of ESL in children with FOE should be further evaluated.

New evidence in adjunctive treatment of focal-onset seizures in adults: a critical appraisal

Anti-seizure medications (ASMs) represent the pillar of the treatment of epilepsy. The rate of drug-resistant epilepsy remained substantially unchanged over time and there is still the need for new and more effective treatment options. Brivaracetam, cenobamate, eslicarbazepine acetate, lacosamide and perampanel are 'third-generation' ASMs. The aim of this article is to summarize the currently available evidence about the relative efficacy and tolerability of the 'third-generation' ASMs as adjunctive treatment of focal-onset seizures in adults. So far, no randomized controlled study directly compared these ASMs, and their comparative efficacy and tolerability have been indirectly evaluated by one network meta-analysis. Sixteen trials were included in the network meta-analysis. The efficacy endpoints were the rates of seizure response and seizure freedom, defined as ≥ 50% and 100% reduction in baseline monthly seizure frequency. The tolerability endpoints were the rate of patients who developed any treatment emergent adverse events (TEAEs) and any TEAE leading to drug discontinuation. Cenobamate had the greatest likelihood of being the best option for the ≥ 50% and 100% seizure frequency reduction. Brivaracetam and lacosamide had the greatest likelihood to rank as the best-tolerated treatments for the occurrence of any TEAE and TEAE leading to discontinuation. Although network meta-analyses are not substitutes of direct comparisons, they can provide valuable evidence about the hierarchy of interventions. Additional real-world data can be useful complement to characterize the clinical profile and therapeutic potentialities of third-generation ASMs.

Movement disorders associated with antiseizure medications: A systematic review

New-onset movement disorders have been frequently reported in association with the use of antiseizure medications (ASMs). The frequency of specific motor manifestations and the spectrum of their semiology for various ASMs have not been well characterized. We carried out a systematic review of literature and conducted a search on CINAHL, Cochrane Library, EMBASE, MEDLINE, PsycINFO, and Scopus from inception to April 2021. We compiled the data for all currently available ASMs using the conventional terminology of movement disorders. Among 5123 manuscripts identified by the search, 437 met the inclusion criteria. The largest number of reports of abnormal movements were in association with phenobarbital, valproic acid, lacosamide, and perampanel, and predominantly included tremor and ataxia. The majority of attempted interventions for all agents were discontinuation of the offending drug or dose reduction which led to the resolution of symptoms in most patients. Familiarity with the movement disorder phenomenology previously encountered in relation with specific ASMs facilitates early recognition of adverse effects and timely institution of targeted interventions.

Long-term therapeutic effect of eslicarbazepine acetate in children: An open-label extension of a cognition study in children aged 6-16 years

OBJECTIVE

In Europe, eslicarbazepine acetate (ESL) is approved as adjunctive therapy for the treatment of focal seizures (FS) in children aged >6 years. In the US, ESL is approved as both monotherapy and adjunctive therapy for the treatment of FS in patients aged ≥4 years. In a phase II study of children aged 6-16 years with FS, ESL had no significant effects on attention or behavioral functioning and decreased seizure frequency during double-blind therapy and a 1-year open-label extension (OLE). This report presents data from an additional 2-year OLE of the phase II study.

METHODS

Previous recipients of ESL or placebo were treated with open-label ESL (10-30 mg/kg/day, adjusted for clinical response and/or adverse events [AEs]). Safety was assessed by incidence of treatment-emergent AEs (TEAEs). Efficacy endpoints were treatment retention time and change from baseline in Clinical Global Impression-Severity (CGI-S) scale scores.

RESULTS

Forty-two patients entered and 31 (73.8%) completed the 2-year OLE. Median treatment retention time was 735 (95% confidence interval 728-741) days. Seven patients (17% of total, 23% of completed) experienced ≥1 TEAE during the 2-year OLE, mostly of mild or moderate intensity. The incidence of serious TEAEs was low (n = 2; 5% of total, 6% of completed) and none were related to ESL. One child was withdrawn because of splenomegaly that was considered possibly related to ESL. The only change from baseline in CGI-S was a 0.5-point reduction in the severity of illness score. All findings were consistent across patient subgroups based on previous double-blind treatment (placebo or ESL) and patient age (6-11 or 12-16 years).

CONCLUSIONS

The majority of patients remained on ESL during the 2-year OLE, and treatment efficacy was maintained. Adverse events were consistent with the known safety profile of ESL, and no new safety signals were identified.

Third-Generation Antiseizure Medications for Adjunctive Treatment of Focal-Onset Seizures in Adults: A Systematic Review and Network Meta-analysis

Background

Brivaracetam (BRV), cenobamate (CNB), eslicarbazepine acetate (ESL), lacosamide (LCM) and perampanel (PER) are antiseizure medications (ASMs) approved for adjunctive treatment of focal-onset seizures. So far, no randomised controlled trial directly compared the efficacy and safety of these drugs.

Objective

We estimated the comparative efficacy and safety of these ASMs for the treatment of focal-onset seizures in adults with epilepsy using a network meta-analysis (NMA).

Methods

We systematically searched (June week 4, 2021) MEDLINE (accessed by PubMed), the Cochrane Central Register of Controlled Trials (CENTRAL), and the US National Institutes of Health Clinical Trials Registry (http://www.clinicaltrials.gov). There were no date limitations or language restrictions. Randomised, double-blinded, controlled, parallel-group, add-on studies that compared oral BRV, CNB, ESL, LCM, and PER versus any comparator over maintenance periods of at least 12 weeks and included adult patients with focal seizures uncontrolled by concomitant ASMs were identified. The efficacy outcomes were the proportions of patients with ≥ 50% and 100% reduction in baseline seizure frequency during the maintenance period. The tolerability outcomes were the proportions of participants who experienced at least one treatment-emergent adverse event (TEAE) and experienced at least one TEAE leading to discontinuation. Effect sizes were estimated by network meta-analyses within a frequentist framework. The hierarchy of competing interventions was established using the surface under the cumulative ranking curve (SUCRA).

Results

Sixteen trials (BRV: n = 3, CNB: n = 1, ESL: n = 4, LCM: n = 4, PER: n = 4) were included, overall enrolling 4507 patients randomised to add-on active treatments (BRV = 803, CNB = 221, ESL =9 90, LCM = 1104, and PER = 1389) and 2246 to add-on placebo. Cenobamate was associated with a higher rate of ≥ 50% seizure frequency reduction than BRV [odds ratio (OR) 2.02, 95% confidence interval (CI) 1.11–3.66], ESL (OR 1.93, 95% CI 1.07–3.48), LCM (OR 1.86, 95% CI 1.04–3.32), and PER (OR 2.07, 95% CI 1.16–3.70). There was a not statistically significant trend favouring CNB over ESL, LCM and PER for the seizure freedom outcome. Brivaracetam (OR 0.61, 95% CI 0.44–0.86) and LCM (OR 0.60, 95% CI 0.40–0.88) were associated with a lower proportion of participants experiencing TEAEs compared to ESL, and patients treated with PER were associated with a higher risk to experience at least one TEAE (OR 1.42, 95% CI 1.02–1.96) than BRV. According to SUCRA, CNB had the greatest likelihood of being the best option for the ≥ 50% and 100% seizure frequency reduction, and BRV and LCM had the highest probabilities of being the best-tolerated treatments.

Conclusions

Cenobamate ranked best for efficacy, and BRV and LCM were best tolerated over the other comparators. Although NMAs cannot replace direct comparisons, they may support physicians in clinical decision making.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40265-021-01661-4.

Indirect treatment comparison of cenobamate to other ASMs for the treatment of uncontrolled focal seizures

OBJECTIVE

The efficacy and safety of cenobamate relative to other antiseizure medications (ASMs) has not been evaluated. An indirect treatment comparison (network meta-analysis) was performed to determine if adjunctive cenobamate increases the odds ratio (OR) for ≥50% responder rate or for withdrawals due to treatment-emergent adverse events (TEAEs) leading to ASM discontinuation versus adjunctive therapy with other ASMs.

METHODS

A systematic literature review was conducted to identify randomized, double-blind, placebo-controlled trials (maintenance phase ≥ 12 weeks) assessing adjunctive ASMs in adults with uncontrolled focal seizures. Cenobamate was compared to a group of seven other ASMs, and to subgroups of branded (brivaracetam, eslicarbazepine acetate, lacosamide, and perampanel) and older (lamotrigine, levetiracetam, and topiramate) ASMs at FDA-recommended daily maintenance doses (FDA-RDMD), at all doses, and at maximum and minimum daily doses. Statistical significance was set at p < 0.05.

RESULTS

Twenty-one studies were eligible for analysis. The placebo-adjusted ≥ 50% responder rate for FDA-RDMD of cenobamate was superior (OR 4.200; 95% CI 2.279, 7.742) to FDA-RDMD of all seven assessed (OR 2.202 95% CI 1.915, 2.532; p = 0.044) and branded ASMs (OR 2.148; 95% CI 1.849, 2.494; p = 0.037). There was no significant difference for ≥50% responder rate between FDA-RDMD of cenobamate and FDA-RDMD of older ASMs (OR 2.617; 95% CI 1.767, 3.878; p = 0.202). No significant differences were identified for ≥50% responder rate when comparing all doses and maximum/minimum doses of cenobamate to all seven, branded, and older ASMs. Cenobamate demonstrated comparable TEAE withdrawal rates to all seven ASMs, branded ASMs, and older ASMs across each of the four dose ranges (all p > 0.05).

SIGNIFICANCE

Patients receiving FDA-RDMD of cenobamate were more likely to have ≥50% seizure reduction compared with FDA-RDMD of the seven assessed ASMs and branded ASMs, without an increase in treatment discontinuation due to TEAEs.

Treatment of Focal-Onset Seizures in Children: Should This Be More Etiology-Driven?

To accelerate the process of licensing antiseizure medication (ASM) in children, extrapolation of efficacy data for focal-onset seizures from adults to children ≥2 or ≥4 years of age is now accepted. We summarized the efficacy evidence from randomized, controlled trials that was used to grant approval for the pediatric indication of focal-onset seizures for the different ASMs available in Europe. Data from high-quality randomized, controlled trials in young children are limited, especially on the use of ASMs in monotherapy. Licensure trials are typically focused on seizure type irrespective of etiology or epilepsy syndrome. We elaborate on the importance of etiology- or syndrome-driven research and treatment, illustrating this with examples of childhood epilepsy syndromes characterized by predominantly focal-onset seizures. Some of these syndromes respond well to standard ASMs used for focal-onset seizures, but others would benefit from a more etiology- or syndrome-driven approach. Advances in molecular genetics and neuroimaging have made it possible to reveal the underlying cause of a child's epilepsy and tailor research and treatment. More high-quality randomized, controlled trials based on etiology or syndrome type are needed, including those assessing effects on cognition and behavior. In addition, study designs such as "N-of-1 trials" could elucidate possible new treatment options in rare epilepsies. Broadening incentives currently in place to stimulate the development and marketing of drugs for rare diseases (applicable to some epilepsy syndromes) to more common pediatric epilepsy types and syndromes might be a means to enable high-quality trials, and ultimately allow more evidence-based treatment in children.

Pharmacogenetics of Drug-Resistant Epilepsy (Review of Literature)

Pharmacogenomic studies in epilepsy are justified by the high prevalence rate of this disease and the high cost of its treatment, frequent drug resistance, different response to the drug, the possibility of using reliable methods to assess the control of seizures and side effects of antiepileptic drugs. Candidate genes encode proteins involved in pharmacokinetic processes (drug transporters, metabolizing enzymes), pharmacodynamic processes (receptors, ion channels, enzymes, regulatory proteins, secondary messengers) and drug hypersensitivity (immune factors). This article provides an overview of the literature on the influence of genetic factors on treatment in epilepsy.

A Review of the Selected and Newer Antiseizure Medications Used in Childhood Epilepsies

There have been additions of newer antiseizure medications in the armamentarium of clinicians for the management of epilepsy. The newer antiseizure medications have advantages of better tolerability, lesser adverse effects, and minimal drug interactions in comparison with conventional antiseizure medications. However, high cost and availability are concerns. There are also peculiar pharmacokinetic and pharmacodynamic considerations for the pediatric age, particularly in the context of age-dependent electroclinical syndromes and precision-based medicine. This review attempts to provide a comprehensive and pragmatic update on newer antiseizure medications.

Safety of Eslicarbazepine Acetate in Elderly Versus Non-Elderly Patients with Focal Seizures: From Pooled Data of Clinical Studies to 8 Years of Post-Marketing Experience

Introduction

The prevalence of epilepsy increases in elderly patients aged > 65 years, and treatment is challenging because clinical data are limited.

Objective

Our objective was to evaluate the safety of eslicarbazepine acetate (ESL) in patients aged ≥ 65 years versus non-elderly patients with focal seizures.

Methods

The safety data of seven phase II and III, double-blind, open-label, randomized clinical studies of ESL in adults were pooled. At least possibly related treatmentemergent adverse events (TEAEs) and ESL post-marketing adverse drug reactions (ADRs) were analyzed separately by age categories.

Results

The most frequently reported at least possibly related TEAEs in elderly (N = 120) versus non-elderly patients (N = 1863) were dizziness (10.8 vs. 20.3%), somnolence (9.2 vs. 12.6%), and hyponatremia (6.7 vs. 1.5%). Elderly patients presented a higher incidence of serious TEAEs (22.5 vs. 7.6%) and at least possibly related serious TEAEs (6.7 vs. 2.5%), probably because treatment was complicated by comorbidities and comedications. After an estimated cumulative exposure of over 2 million patient-months worldwide and 8 years of post-marketing surveillance, hyponatremia was the most frequently reported ADR (n = 232), accounting for 14.6% and 6.8% of the ADRs reported in elderly (n = 473) and non-elderly patients (n = 2406), respectively. This was followed by ADR/safety information such as drug–dose titration not performed (7.0 vs. 5.4%), product use in unapproved indication (4.9 vs. 1.9%), off-label use (3.4 vs. 2.2%), dizziness (3.4 vs. 3.5%), and seizure (2.1 vs. 5.8%).

Conclusion

No specific safety issue was identified from the pooled studies for elderly compared with non-elderly patients. After 8 years of post-marketing surveillance, the qualitative safety of ESL remains similar to that observed in the clinical studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40264-021-01097-5.

Pharmacotherapy for Seizures in Tuberous Sclerosis Complex

Epilepsy is one of the main symptoms affecting the lives of individuals with tuberous sclerosis complex (TSC), causing a high rate of morbidity. Individuals with TSC can present with various types of seizures, epilepsies, and epilepsy syndromes that can coexist or appear in relation to age. Focal epilepsy is the most frequent epilepsy type with two developmental and epileptic encephalopathies: infantile spasms syndrome and Lennox-Gastaut syndrome. Active screening and early management of epilepsy is recommended in individuals with TSC to limit its consequences and its impact on quality of life, cognitive outcome and the economic burden of the disease. The progress in the knowledge of the mechanisms underlying epilepsy in TSC has paved the way for new concepts in the management of epilepsy related to TSC. In addition, we are moving from traditional "reactive" and therapeutic choices with current antiseizure medications used after the onset of seizures, to a proactive approach, aimed at predicting and preventing epileptogenesis and the onset of epilepsy with vigabatrin, and to personalized treatments with mechanistic therapies, namely mechanistic/mammalian target of rapamycin inhibitors. Indeed, epilepsy linked to TSC is one of the only epilepsies for which a predictive and preventive approach can delay seizure onset and improve seizure response. However, the efficacy of such interventions on long-term cognitive and psychiatric outcomes is still under investigation.

Suicidality Risk of Newer Antiseizure Medications: A Meta-analysis

Importance

Most antiseizure medications (ASMs) carry a US Food and Drug Administration-mandated class label warning of increased suicidality risk, based on a meta-analysis comparing suicidality between individuals treated with medications vs placebo in randomized clinical trials done before 2008. ASMs approved since then carry this warning although they were not similarly studied.

Objective

To review all placebo-controlled phase 2 and 3 studies of 10 ASMs approved since 2008 to evaluate the risk of suicidality of these drugs compared with placebo.

Data Sources

Primary publications and secondary safety analyses in PubMed of all phase 2 and 3 randomized placebo-controlled epilepsy trials of ASMs approved since 2008, using keywords epilepsy, antiepileptic drugs, seizures, suicidality, suicidal ideation, and the names of individual drugs.

Study Selection

All phase 2 and 3 randomized clinical trials of adjunctive treatment of drug-resistant epilepsy and their secondary safety analyses.

Data Extraction and Synthesis

Articles were reviewed for frequency of suicidality (ideation, attempts, and completed suicides). Mode of suicidality ascertainment included treatment-emergent adverse event reports, Standardized Medical Dictionary for Regulatory Activities queries for events in prespecified categories including suicidal ideation and behavior, prospective collection of suicidality data as a prespecified safety outcome using the Columbia-Suicide Severity Rating Scale, and retrospective evaluation by blinded review using the Columbia-Classification Algorithm of Suicide Assessment. A meta-analysis compared risk for drugs vs placebo of each outcome for all drugs overall and by individual drugs and trials.

Main Outcomes and Measures

Suicidality (total and by ideation), attempts, and completed suicides.

Results

Excluding studies that did not evaluate suicidality (everolimus and fenfluramine) or did not evaluate it prospectively (lacosamide, ezogabine, and clobazam), 5 drugs were analyzed: eslicarbazepine, perampanel, brivaracetam, cannabidiol, and cenobamate. Suicidality was evaluated in 17 randomized clinical trials of these drugs, involving 5996 patients, of whom 4000 patients were treated with ASMs and 1996 with placebo. There was no evidence of increased risk of suicidal ideation (drugs vs placebo overall risk ratio, 0.75; 95% CI, 0.35-1.60) or attempt (risk ratio, 0.75; 95% CI, 0.30-1.87) overall or for any individual drug. Suicidal ideation occurred in 12 of 4000 patients treated with ASMs (0.30%) vs 7 of 1996 patients treated with placebo (0.35%) (P = .74). Three patients treated with ASMs and no patients treated with placebo attempted suicide (P = .22). There were no completed suicides.

Conclusions and Relevance

There is no current evidence that the 5 ASMs evaluated in this study increase suicidality in epilepsy and merit a suicidality class warning.

Dietary medium chain triglycerides for management of epilepsy: New data from human, dog, and rodent studies

Many studies show that glucose metabolism in epileptic brain areas can be impaired. Energy is crucial to maintain normal brain function, including ion and neurotransmitter balances. Energy deficits can lead to disruption of ion gradients, which can trigger neuronal depolarization and generation of seizures. Thus, perturbed metabolic processing of glucose in epileptogenic brain areas indicates a specific nutritional need for people and animals with epilepsy, as they are likely to benefit from auxiliary brain fuels other than glucose. Ketogenic diets provide the ketone bodies acetoacetate and β-hydroxybutyrate, which can be used as auxiliary fuel by the brain. In approximately 50% children and adults with certain types of epilepsy, who can tolerate and maintain these dietary regimens, seizure frequency can be effectively reduced. More recent data demonstrate that addition of medium chain triglycerides (MCTs), which provide the medium chain fatty acids octanoic and decanoic acid, as well as ketone bodies as auxiliary brain energy, can be beneficial in rodent seizure models, and dogs and humans with epilepsy. Here, this evidence is reviewed, including tolerance in 65% of humans, efficacy studies in dogs, possible anticonvulsant mechanisms of actions of MCTs, and specifically decanoic acid as well as metabolic and antioxidant mechanisms. In conclusion, MCTs are a promising adjunct to standard pharmacological treatment for both humans and dogs with epilepsy, as they lack central nervous system side effects found with current antiepileptic drugs. There is now a need for larger clinical trials in children, adults, and dogs to find the ideal composition and doses of MCTs and the types of epilepsy that respond best.

Eslicarbazepine acetate add-on therapy for drug-resistant focal epilepsy

BACKGROUND

This is an update of a review first published in 2011, and last updated in 2017. Most people with epilepsy have a good prognosis, but up to 30% of people continue to have seizures despite several regimens of antiepileptic drugs. In this review, we summarized the current evidence regarding eslicarbazepine acetate (ESL) when used as an add-on treatment for drug-resistant focal epilepsy.

OBJECTIVES

To evaluate the efficacy and tolerability of ESL when used as an add-on treatment for people with drug-resistant focal epilepsy.

SEARCH METHODS

For this update, we searched the following databases on 10 September 2020: Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid). CRS Web includes randomized or quasi-randomized, controlled trials from Specialized Registers of Cochrane Review Groups including Epilepsy, CENTRAL, PubMed, Embase, ClinicalTrials.gov and the WHO ICTRP. There were no language restrictions. We reviewed the reference lists of retrieved studies and contacted the manufacturers of ESL and experts in the field for information about any unpublished or ongoing studies.

SELECTION CRITERIA

Randomized placebo-controlled double-blind add-on trials of ESL in people with drug-resistant focal epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted data. Outcomes investigated included 50% or greater reduction in seizure frequency, seizure freedom, treatment withdrawal, adverse effects and drug interactions. Primary analyses were by intention to treat (ITT). The dose-response relationship was evaluated in regression models.

MAIN RESULTS

We included seven trials (2185 participants, aged 2 to 77 years), which were at low or unclear risk of bias apart from a high risk of attrition bias; all studies were funded by the pharmaceutical company, BIAL. The overall risk ratio (RR) for 50% or greater reduction in seizure frequency was 1.57 (95% confidence interval (CI) 1.34 to 1.83). For adults, the RR was 1.71 (95% CI 1.42 to 2.05; 5 studies, 1799 participants; moderate-certainty evidence); for children aged six to 18 years, the RR was 1.35 (95% CI 0.98 to 1.87; 2 studies, 322 participants; moderate-certainty evidence). Dose regression analysis showed evidence that ESL reduced seizure frequency with an increase in efficacy with increasing doses of ESL. ESL was associated with seizure freedom (RR 3.16, 95% CI 1.73 to 5.78; 6 studies, 1922 participants; moderate-certainty evidence). Participants were more likely to have ESL withdrawn for adverse effects (RR 2.72, 95% CI 1.66 to 4.46; 7 studies, 2185 participants; moderate-certainty evidence), but not for any reason (RR 1.25, 95% CI 0.93 to 1.70; 7 studies, 2185 participants; moderate-certainty evidence). The following adverse effects were associated with ESL: dizziness (RR 2.77, 99% CI 1.85 to 4.15); nausea (RR 2.55, 99% CI 1.39 to 4.67); somnolence (RR 1.75, 99% CI 1.18 to 2.61); diplopia (RR 4.07, 99% CI 1.86 to 8.89); and vomiting (RR 2.37, 99% CI 1.19 to 4.74). Overall, the certainty of the evidence was moderate due to a high discontinuation rate in studies of adults.

AUTHORS' CONCLUSIONS

ESL reduces seizure frequency when used as an add-on treatment for adults with drug-resistant focal epilepsy. The trials included in this review were of short-term duration. In addition, this update found that ESL may reduce seizure frequency in children from 6 to 18 years of age; however the results are inconclusive.

Comparative Economic Outcomes in Patients with Focal Seizure Initiating First-Line Eslicarbazepine Acetate Monotherapy versus Generic Antiseizure Drugs

Objective

To examine the association between initiating first-line (1L) monotherapy with eslicarbazepine acetate (ESL) vs a generic antiseizure drug (ASD) and healthcare resource utilization (HCRU) and charges in adults with treated focal seizures (FS).

Methods

This was a retrospective analysis of Symphony Health’s Integrated Dataverse^® open-source claims data. Two cohorts were identified as having initiated 1L monotherapy with ESL or literature-defined generic ASDs. Linear regression models with person fixed effects and inverse probability treatment weights assessed the relative additional changes in HCRU and charges among patients who received ESL compared to generic ASD.

Results

A total of 250 and 43,220 patients initiated ESL (48.3 years; 57.2% female) or a generic ASD (54.5 years; 58.1% female), respectively. Compared to patients initiating a generic ASD, patients treated with ESL had additional reductions of 11.8 percentage points in the likelihood of any all-cause outpatient visits (P<0.001), 7.4 percentage points in the likelihood of any emergency department (ED) visits (P=0.013), and 22.7 percentage points in the likelihood of any FS-related outpatient visits (P<0.001). Patients initiating ESL had greater reductions in mean charges for all-cause medical ($2620; P=0.002), outpatient ($1995; P=0.005), and non-FS-related medical ($2708; P<0.001) services. Patients initiating ESL had greater relative increases in mean total prescription ($1368; P<0.001) and ASD-related prescription ($1636; P<0.001) charges, but greater relative reductions in non-ASD prescription ($269; P=0.032) charges. The increases in prescription charges were of a lower magnitude than the decreases in medical charges.

Conclusion

Initiation of ESL as 1L monotherapy was associated with statistically significantly greater reductions in any use of several all-cause and FS-related services, number of visits, and charges compared to initiation of a generic ASD as 1L monotherapy in patients with FS. Initiation of a generic ASD as 1L monotherapy was associated with significantly smaller increases in total prescription charges and ASD-related prescription charges.

Healthcare Resource Utilization Among Patients with Focal Seizures Treated with Eslicarbazepine Acetate in the US Long-Term Care Setting: A Retrospective Claims Database Analysis

Introduction

The aim of this study was to compare healthcare resource utilization (HCRU) before and after initiation of eslicarbazepine acetate (ESL) in the long-term care (LTC) setting (rehabilitation center, mental health center, LTC non-skilled nursing facility/assisted-living facility, home health, assisted living, nursing home, other/unknown).

Methods

This retrospective analysis used IQVIA’s New Data Warehouse, which includes deterministically linked LTC, prescription, and professional fee claims data and IQVIA Hospital Charge Data Master database. The study period was 1 April 2013 to 31 December 2019. The index date was the date of ESL initiation in the LTC setting. Inclusion criteria were: (1) ≥ 1 new ESL prescription between 1 April 2014 and 31 December 2018; (2) diagnosis of focal seizure (FS) during the 12 months pre-index date; and (3) no ESL prescription during the 12-month period pre-index. A 12-month pre-post analysis compared epilepsy-specific and all-cause HCRU before and after ESL initiation. Categorical variables were compared with McNemar’s tests.

Results

A total of 307 patients (mean age 52.2 years, 57.7% male) with FS were included, of whom 24.8% were in nursing homes. Patients used a mean of 3.1 antiseizure drugs prior to initiation of ESL, and 87.9% of patients initiated ESL as adjunctive treatment. There were significant reductions in proportion of patients with epilepsy specific physician office visits, emergency department (ED) visits, hospitalizations, and all-cause physician office visits and hospitalizations in the post-index period compared to the pre-index period (P < 0.05). Similar results were observed in sensitivity (patients with an epilepsy diagnosis) and subgroup analyses [presence or absence of intellectual developmental disorders or age (≥ 65 and < 65 years)].

Conclusion

Proportion of patients with epilepsy-specific physician office visits, ED visits, hospitalizations, and all-cause physician office visits and hospitalizations were significantly reduced following initiation of ESL in patients with FS in LTC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-021-00244-5.

Anti-seizure medications and efficacy against focal to bilateral tonic-clonic seizures: A systematic review with relevance for SUDEP prevention

We conducted a systematic review of anti-seizure medications (ASMs) and their efficacy for the control of focal to bilateral tonic-clonic seizures (FBTCS). FBTCS, especially when nocturnal, are recognized as one of the major risk factors for Sudden Unexpected Death in Epilepsy (SUDEP). We searched different online databases for all the randomized, double-blinded, and placebo-controlled clinical trials of ASMs that were FDA-approved after 1990 and that reported specifically on the reduction in FBTCS; when possible, this was compared to reduction in focal impaired awareness (FIA) seizures. The ASMs that yielded the most data (3 or more studies) were topiramate (TPM), followed by tiagabine (TGB), brivaracetam (BRV), and lamotrigine (LTG). TPM trials showed a reduction in FBTCS of 44.8% to 100% (4.5-99% over placebo); TGB 21.8% to 46.7% (21.8-61% over placebo); BRV 33.9% to 82.1% (11.6-57.4% over placebo); and LTG 55.2% (20.3-52% over placebo). Promising results, but with data from only one or two studies, were seen with cenobamate (18-59% efficacy above placebo), lacosamide (45.1-78.7%), levetiracetam (40.1-60.3%), oxcarbazepine (58.5-81.5%), and gabapentin (50-53.8%). Higher responses were often seen at higher doses, including at doses above those currently approved by the FDA. Results specific to nocturnal FBTCS were never reported for any ASM. Moreover, complete freedom from FBTCS specifically was very rarely reported, despite its relevance for SUDEP prevention. In conclusion, there are few data specifically comparing the efficacy of ASMs for prevention of FBTCS despite the known strong association of BTCS with SUDEP. This review was our attempt at filling a gap in the literature and calling for universal reporting of data specific to BTC seizure reduction in all future studies, preferably including specific reporting on nocturnal BTCS. This will help enable rational ASM selection to minimize BTC seizures and thereby decrease the risk of SUDEP.

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.

New anti-seizure medication for elderly epilepsy patients - a critical narrative review

Introduction: The number of elderly patients with epilepsy is growing in resource rich countries due to demographic changes and increased longevity. Management in these patients is challenging as underlying etiology, co-morbidities, polypharmacy, age-related pharmacokinetic and pharmacodynamic changes need to be considered.Areas covered: Lacosamide, eslicarbazepine acetate, brivaracetam, and perampanel have been approved in the USA and Europe for monotherapy and/or adjunctive treatment of seizures in the last few years. The authors review the pharmacological properties and safety profile of these drugs and provide recommendations for their use in in the elderly.Expert opinion: There are only limited data available on more recent antiseizure medications (ASMs). Drugs with a low risk of interaction (lacosamide, brivaracetam) are preferred choices. Once daily formulations (perampanel and eslicarbazepine acetate) have the advantage of increased compliance. Intravenous formulations (brivaracetam and lacosamide) are useful in emergency situations and in patients who have difficulties to swallow. Dose adjustments are necessary for all ASMs used in the elderly with slow titration and lower target doses than in the regulatory trials. The adverse event profile does not significantly differ from that found in the general adult population.

Ketogenic Diet Therapies for Seizures and Status Epilepticus

Ketogenic diet therapies are high-fat, low-carbohydrate diets designed to mimic a fasting state. Although initially developed nearly one century ago for seizure management, most clinical trials for the management of drug-resistant epilepsy in children as well as adults have been conducted over the last 3 decades. Moreover, ketogenic diets offer promising new adjunctive strategies in the critical care setting for the resolution of acute status epilepticus when traditional antiseizure drugs and anesthetic agents fail. Here, we review the history of ketogenic diet development, the clinical evidence supporting its use for the treatment of drug-resistant epilepsy in children and adults, and the early evidence supporting ketogenic diet feasibility, safety, and potential efficacy in the management of status epilepticus.

Associations between seizure severity change and patient characteristics, changes in seizure frequency, and health-related quality of life in patients with focal seizures treated with adjunctive eslicarbazepine acetate: Post hoc analyses of clinical trial results

The relationships between seizure severity change and patient characteristics, changes in seizure frequency, and health-related quality of life (HRQoL) may be important for determining the overall impact of medication therapy on patients with epilepsy. The objectives of these post hoc analyses of the global Phase III 093-0304 trial (NCT00988429, Study 304) of adjunctive eslicarbazepine acetate (ESL) in patients with refractory focal (partial-onset) seizures (FS) were to evaluate associations between seizure severity change, measured by the Seizure Severity Questionnaire (SSQ), and 1) patient characteristics, 2) seizure frequency change, standardized as the seizure frequency (SSF) per 28-day period, and 3) change in HRQoL, evaluated by the Quality of Life in Epilepsy Inventory-31 (QOLIE-31) and the Montgomery-Åsberg Depression Rating Scale (MADRS). The analyses were conducted on the per-protocol population (PPP) of patients who were randomized to a placebo arm (n = 188) or an ESL-active group that included treatment with adjunctive ESL 800 mg once daily (QD; n = 184) or adjunctive ESL 1200 mg QD (n = 175). General linear models (GLM) were used to measure the association between SSQ change and patient baseline characteristics or percentage change in the SSF from baseline. Associations between changes in the SSQ and changes in the QOLIE-31 and MADRS were examined using GLM with patient baseline characteristics as covariates. Subgroup analyses were performed for patients in the ESL-active group and those treated with ESL 800 mg or ESL 1200 mg. Minimal clinically important difference (MCIDs) thresholds were used to assess improvements in SSQ scores. The analyses included 547 per-protocol patients. Patients using 1 antiepileptic drug (AED) at baseline had greater improvements in the SSQ compared with those receiving 2 AEDs (P = 0.0606). Treatment with ESL 1200 mg was significantly associated with clinically meaningful improvements in the SSQ (P = 0.0005). The SSQ improvements were significantly associated with an SSF reduction of ≥75%, compared with no reduction (P < 0.0001). In the PPP and the ESL-active group, SSQ improvements were significantly associated with improvements in QOLIE-31 Total Score (TS; P < 0.0001) and the Seizure Worry (SW; P < 0.0001) and Social Functioning (SF; P = 0.0030) subscales. In the ESL 1200 mg subgroup, SSQ improvements were significantly associated with improvements in QOLIE-31 TS (P < 0.0001) and the SW (P < 0.0001) and Energy/Fatigue (EF; P = 0.0007) subscales. In the ESL 800 mg subgroup, improvements in the SSQ were significantly associated with improvements in QOLIE-31 TS (P = 0.0362) and the SW (P = 0.0241) subscale. There was no significant association between changes in the SSQ and changes in the MADRS in patients treated with ESL. These findings demonstrated that in this clinical trial population, adding ESL to baseline AED therapy had utility for decreasing seizure severity and improving HRQoL. There were no significant associations between changes in seizure severity and changes in depressive symptoms in patients with FS.

Comparative analysis of the safety and tolerability of eslicarbazepine acetate in older (≥60 years) and younger (18-59 years) adults

OBJECTIVE

To investigate the safety and tolerability of eslicarbazepine acetate (ESL), a once-daily oral anti-seizure drug (ASD), in older and younger adult patient populations.

METHODS

Two post-hoc pooled data analyses were performed: one from three Phase III studies in patients with focal (partial-onset) seizures who were taking 1-3 concomitant ASDs; the other from five Phase II studies in patients from non-epilepsy populations not taking other ASDs chronically and/or at a clinically-effective anti-seizure dose. The frequencies of treatment-emergent adverse events (TEAEs) were calculated for the older (≥60 years) and younger (18-59 years) adults separately.

RESULTS

In the focal seizures study pool, 4.1 % of patients (58/1431) were aged ≥60 years. The overall frequency of TEAEs was 77.5 % in older ESL-treated patients and 72.6 % in younger ESL-treated patients (p = 0.495). For patients who received placebo, the overall frequency of TEAEs was 50.0 % in the older adults and 57.5 % in the younger adults (p = 0.531). The overall placebo-adjusted frequency of TEAEs was 27.5 % in older adults and 15.1 % in younger adults. The placebo-adjusted frequencies of the TEAEs dizziness, somnolence, headache, nausea, diplopia, blurred vision, and ataxia were ≥5 % higher, and frequencies of vomiting and vertigo were ≥2 % higher in older than younger adults. The overall frequency of TEAEs leading to discontinuation was 15.0 % in older ESL-treated patients and 17.6 % in younger ESL-treated patients (p = 0.647); the frequency increased with increasing ESL dose. For patients who received placebo, the overall frequency of TEAEs leading to discontinuation was 5.6 % in older adults and 6.6 % in younger adults (p = 0.847). In the non-epilepsy study pool, 30.2 % of patients (515/1705) were aged ≥60 years. The overall frequency of TEAEs was 56.9 % in older ESL-treated patients and 58.8 % in younger ESL-treated patients. The placebo-adjusted frequencies were 14.9 % in older and 15.1 % in younger ESL-treated patients. The placebo-adjusted frequencies of the TEAEs nausea, vomiting, fatigue, and vertigo were ≥2 % higher in older adults, whereas somnolence was ≥2 % higher in younger adults. The overall frequency of TEAEs leading to discontinuation was 18.3 % in older ESL-treated patients and 12.1 % in younger ESL-treated patients (p = 0.003); frequencies were not related to ESL dose. For patients who received placebo, the overall frequency of TEAEs leading to discontinuation was 8.0 % in older adults and 5.6 % in younger adults (p = 0.407).

CONCLUSION

Analyses of adverse event data support the safety and tolerability of ESL in adults aged ≥60 years. In the limited number of older patients with focal seizures taking ESL plus concomitant ASDs (n = 40), the frequency of TEAEs was generally higher than in younger adults. However, in the non-epilepsy patient group (in which the number of older patients was ten times larger; 427 patients taking ESL without concomitant ASDs), no marked age-related TEAE differences were observed, suggesting that increased ASD load associated with adjunctive therapy may complicate treatment selection in older patients, due to risk of increased adverse events. As is common practice for all ASDs, balancing clinical response and tolerability is needed in this vulnerable group of patients.

Inhibitory Effect of Eslicarbazepine Acetate and S-Licarbazepine on Nav1.5 Channels

Eslicarbazepine acetate (ESL) is a dibenzazepine anticonvulsant approved as adjunctive treatment for partial-onset epileptic seizures. Following first pass hydrolysis of ESL, S-licarbazepine (S-Lic) represents around 95% of circulating active metabolites. S-Lic is the main enantiomer responsible for anticonvulsant activity and this is proposed to be through the blockade of voltage-gated Na⁺ channels (VGSCs). ESL and S-Lic both have a voltage-dependent inhibitory effect on the Na⁺ current in N1E-115 neuroblastoma cells expressing neuronal VGSC subtypes including Na_v1.1, Na_v1.2, Na_v1.3, Na_v1.6, and Na_v1.7. ESL has not been associated with cardiotoxicity in healthy volunteers, although a prolongation of the electrocardiographic PR interval has been observed, suggesting that ESL may also inhibit cardiac Na_v1.5 isoform. However, this has not previously been studied. Here, we investigated the electrophysiological effects of ESL and S-Lic on Na_v1.5 using whole-cell patch clamp recording. We interrogated two model systems: (1) MDA-MB-231 metastatic breast carcinoma cells, which endogenously express the "neonatal" Na_v1.5 splice variant, and (2) HEK-293 cells stably over-expressing the "adult" Na_v1.5 splice variant. We show that both ESL and S-Lic inhibit transient and persistent Na⁺ current, hyperpolarise the voltage-dependence of fast inactivation, and slow the recovery from channel inactivation. These findings highlight, for the first time, the potent inhibitory effects of ESL and S-Lic on the Na_v1.5 isoform, suggesting a possible explanation for the prolonged PR interval observed in patients on ESL treatment. Given that numerous cancer cells have also been shown to express Na_v1.5, and that VGSCs potentiate invasion and metastasis, this study also paves the way for future investigations into ESL and S-Lic as potential invasion inhibitors.

Impact of Early Initiation of Eslicarbazepine Acetate on Economic Outcomes Among Patients with Focal Seizure: Results from Retrospective Database Analyses

INTRODUCTION

This study assessed the association between early initiation of eslicarbazepine acetate (ESL) as first-line therapy (1L cohort) or as first adjunctive regimen to either levetiracetam (LEV) or lamotrigine (LTG) (add-on cohort), and healthcare resource utilization (HCRU) and charges among adults with treated focal seizures (FS).

METHODS

This retrospective, longitudinal cohort analysis used Symphony Health's Integrated Dataverse (IDV®) claims data to identify patients aged ≥ 18 years with a diagnosis of FS who had a new prescription for ESL between April 2015 and June 2018. Baseline was the 90-day period immediately prior to the date of the first-dispensed claim for ESL (index date) with a follow-up of 1-4 consecutive 90-day periods. Linear regression models were estimated to assess changes in HCRU and charge outcomes.

RESULTS

There were 274 and 153 patients who received ESL in the 1L cohort and add-on cohort, respectively. The 1L cohort experienced significant reductions from baseline during follow-up in all-cause inpatient (IP; P < 0.0001), emergency room (ER; P < 0.0001), and outpatient (OP; P < 0.0001) visits; FS-related IP (P = 0.006) and OP (P < 0.0001) visits; total, medical, all-cause ER and OP, and FS-related medical charges (P < 0.05); and significant increases in total prescription and anti-seizure drug (ASD)-related prescription (P < 0.001) charges. The add-on cohort experienced significant reductions in all-cause IP (P = 0.009) and all-cause and FS-related OP visits (P < 0.0001 for both) and significant increases in total prescription and ASD-related prescription (P < 0.001) charges during the follow-up period. In both cohorts, the increases in prescription charges were smaller than the reduction in total medical charges.

CONCLUSION

Early initiation of ESL as 1L or add-on therapy was associated with statistically significant reductions in all-cause IP and all-cause and FS-related OP visits during follow-up compared to baseline. The 1L cohort also had statistically significant reductions in all-cause ER visits, FS-related IP visits, and total, medical, all-cause ER and OP, and FS-related medical charges. Knowledge of healthcare resource utilization (HCRU) and costs of care in patients taking anti-seizure drugs (ASDs) is required to inform prescribing and formulary decision-making. Levetiracetam (LEV) and lamotrigine (LTG) are the most widely used first-line (1L) ASDs in the USA. Eslicarbazepine acetate (ESL), a third-generation ASD with sodium channel-modulating activity, is typically used in later lines of therapy. Sodium channel-blocking anti-seizure drugs may represent an effective treatment option for patients with epilepsy in the 1L setting. This study assessed the association between early initiation of ESL as 1L therapy (1L cohort) or as first adjunctive therapy to either LEV or LTG (add-on cohort), and HCRU and charges among adults with treated focal seizures (FS). The results showed that following ESL initiation the 1L cohort experienced significant reductions in all-cause inpatient (IP), emergency room (ER), and outpatient (OP) visits; FS-related IP and OP visits; and total, medical, all-cause ER and OP, and FS-related medical charges, and significant increases in total prescription and ASD-related prescription charges. The add-on cohort showed significant reductions in all-cause IP and all-cause and FS-related OP visits and significant increases in total prescription and ASD-related prescription charges. In both cohorts, the increases in prescription charges were smaller than the reduction in total medical charges. These data imply that use of ESL as 1L therapy in adult patients with FS could help conserve scarce healthcare resources and reduce the burden on healthcare budgets. These findings may inform selection of ASD therapy in this patient population.

Eslicarbazepine Acetate: A Review in Focal-Onset Seizures

Eslicarbazepine acetate (Zebinix^®), a voltage-gated sodium channel blocker, is a once-daily, orally administered anti-seizure medication available in the EU for use as monotherapy in adults with newly diagnosed focal-onset seizures and as adjunctive therapy in adults, adolescents and children aged > 6 years with focal-onset seizures. In adult patients, adjunctive eslicarbazepine acetate was generally associated with a significant decrease in seizure frequency and an increase in responder rate compared with placebo. The drug was also an effective monotherapy agent in adult patients, demonstrating noninferiority to controlled-release carbamazepine, in terms of seizure freedom rates. In paediatric patients, eslicarbazepine acetate provided seizure control when administered as adjunctive therapy, with the benefits appearing to be dependent on age and dose. The antiepileptic efficacy of eslicarbazepine acetate as adjunctive therapy or as monotherapy was maintained during longer-term extension studies, with each extension study period being up to 2 years. Oral eslicarbazepine acetate was generally well tolerated when administered as adjunctive therapy or monotherapy in adult patients and when administered as adjunctive therapy in paediatric patients, with most adverse events being of mild or moderate intensity. In conclusion, with the convenience of once-daily administration, eslicarbazepine acetate is an effective and generally well-tolerated treatment option for adults, adolescents and children aged > 6 years with focal-onset seizures.

Randomized phase 2 study of adjunctive cenobamate in patients with uncontrolled focal seizures

Objective

To evaluate the efficacy and safety of adjunctive cenobamate 200 mg/d in patients with uncontrolled focal (partial-onset) seizures despite treatment with 1 to 3 antiepileptic drugs.

Methods

In this multicenter, double-blind, placebo-controlled study, adults 18 to 65 years of age with focal seizures were randomized 1:1 (cenobamate:placebo) after an 8-week baseline period. The 12-week double-blind treatment period consisted of a 6-week titration phase and a 6-week maintenance phase. The primary outcome was percent change in seizure frequency (from baseline) per 28 days during double-blind treatment.

Results

Two hundred twenty-two patients were randomized; 113 received cenobamate and 109 received placebo; and 90.3% and 90.8% of patients, respectively, completed double-blind treatment. Median baseline seizure frequency was 6.5 in 28 days (range 0–237). Compared to placebo, cenobamate conferred a greater median percent seizure reduction (55.6% vs 21.5%; p < 0.0001) The responder rate (≥50% reduction in seizure frequency) was 50.4% for cenobamate and 22.2% for placebo (p < 0.0001). Focal seizures with motor component, impaired awareness, and focal to bilateral tonic-clonic seizures were significantly reduced with cenobamate vs placebo. During maintenance, 28.3% of cenobamate-treated and 8.8% of placebo-treated patients were seizure-free. Treatment-emergent adverse events reported in >10% in either group (cenobamate vs placebo) were somnolence (22.1% vs 11.9%), dizziness (22.1% vs 16.5%), headache (12.4% vs 12.8%), nausea (11.5% vs 4.6%), and fatigue (10.6% vs 6.4%).

Conclusion

Adjunctive treatment with cenobamate 200 mg/d significantly improved seizure control in adults with uncontrolled focal seizures and was well tolerated.

ClinicalTrials.gov identifier

NCT01397968.

Classification of evidence

This study provides Class I evidence that, for patients with uncontrolled focal seizures, adjunctive cenobamate reduces seizures.

Eslicarbazepine in patients with brain tumor-related epilepsy: a single-center experience

PURPOSE

Brain tumor-related epilepsy (BTRE) is frequent in patients affected with glioma. Most patients have refractory seizures and require polytherapy. Promising treatment options derive from the development of novel anti-epileptic drugs (AEDs), like Eslicarbazepine (ESL), whose role in BTRE has not yet been explored. Our aim was to report a retrospective cohort of patients affected by BTRE treated with ESL as an adjunctive therapy and to discuss the potential role of this third-generation AED in this clinical context.

METHODS

We analyzed a single-center, retrospectively collected cohort of patients affected by glioma and BTRE, treated with ESL as an adjunctive therapy.

RESULTS

Analysis included 5 males and 3 females with age ranging from 37 to 75 years (mean = 55.5). Mean baseline Karnofsky performance status was 87.5 (range 70-100). Patients were affected by diffuse astrocytoma (3), low grade oligodendroglioma (2), anaplastic glioma (2) and glioblastoma (1). Mean follow-up was 19 months (range 6-59). Mean dose at the last follow-up was 950 mg daily. Mean weekly seizures in the month before initiation of ESL numbered 17.6 (range 0.25-50). At the last follow-up, mean weekly seizures were 2.2 (range 0-10), i.e. significantly lower than baseline (p = 0.03). The mean reduction of seizures achieved after introduction of ESL was 65%, with 6/8 patients (75%) showing a reduction of more than 50%. Two patients (25%) were seizure free.

CONCLUSIONS

This single-center experience suggests that ESL may be a well-tolerated, efficacious option as an add-on drug in the treatment of BTRE.

Analysis of cutaneous allergic reactions in clinical trials of eslicarbazepine acetate

OBJECTIVES

To evaluate cutaneous allergic reactions in clinical trials of adjunctive eslicarbazepine acetate (ESL) for focal seizures.

MATERIALS AND METHODS

Data were analyzed from three phase III randomized, double-blind, placebo-controlled studies of adjunctive ESL in adults (placebo, n = 426; ESL, n = 1021) and two randomized, double-blind, placebo-controlled studies (and open-label extensions [OLEs]) of adjunctive ESL in children aged 4-17 years (placebo, n = 160; ESL, n = 202; OLE, n = 337).

RESULTS

Adult studies: Rash (ESL 1.9%, placebo 0.9%) and pruritus (ESL 1.2%, placebo 0.9%) were the most frequent rash-related treatment-emergent adverse events (TEAEs). Most rash-related TEAEs were mild or moderate in severity. Incidence of rash increased with increasing ESL dose, but was not higher for patients who initiated treatment with higher ESL doses. Pediatric studies: Allergic dermatitis (ESL 3.0%, placebo 0) and rash (controlled studies: ESL 1.0%, placebo 1.3%; OLE periods: ESL ≤1.2%) were the most frequent rash-related TEAEs. There was one case of DRESS in the ESL group. Most rash-related TEAEs were mild or moderate in severity and judged as not related to treatment with ESL.

CONCLUSIONS

Serious skin rashes were rare during adult and pediatric clinical trials of ESL. Although the incidence of rash with ESL was low, it is important for patients/caregivers to be made aware of the potential signs and symptoms associated with serious skin rashes.

Efficacy and safety of eslicarbazepine acetate as adjunctive therapy for refractory focal-onset seizures in children: A double-blind, randomized, placebo-controlled, parallel-group, multicenter, phase-III clinical trial

PURPOSE

This was a phase-III, randomized, double-blind, placebo-controlled study aimed to evaluate efficacy and tolerability of eslicarbazepine acetate (ESL) as adjunctive therapy in pediatric patients with refractory focal-onset seizures (FOS).

METHODS

Children (2-18 years old) with FOS, receiving 1-2 antiepileptic drugs, were randomized to ESL or placebo. Treatment was started at 10 mg/kg/day, up-titrated up to 20-30 mg/kg/day, and maintained for 12 weeks, followed by one-year open-label follow-up. Primary efficacy endpoints were relative reduction in standardized seizure frequency (SSF) and proportion of responders (≥50% SSF reduction) from baseline. Safety was evaluated by the incidence of treatment-emergent adverse events (TEAEs).

RESULTS

The intention-to-treat (ITT) set included 134 patients randomized to ESL and 129 to placebo; 89.6% and 91.5%, respectively, completed the trial. An unbalanced number of seizures at baseline were observed between groups. Least square (LS) mean relative change in SSF from baseline was higher in the ESL group (-18.1%) than in placebo (-8.6%). Proportion of responders between ESL and placebo groups was not statistically different. A post hoc analysis showed greater relative reduction in SSF in patients above 6 years old treated with ESL 20 or 30 mg/kg/day compared with placebo; this was significant in patients above 6 years old treated with ESL 30 mg/kg/day (LS mean difference: 31.9%; p = 0.0478). The observed safety profile in children was consistent with that established in adult studies.

CONCLUSIONS

Adjunctive ESL treatment was well-tolerated, but this trial failed to demonstrate that ESL was more effective than placebo in the predefined efficacy endpoints; factors that may have contributed to this outcome, affecting particularly the young age group, include etiological heterogeneity, difficulty in recognizing simple partial seizures, high seizure frequency with risk of imbalance, and underestimation of the efficacious dose range.

Antiepileptic Drugs in Pediatrics

Epilepsy affects approximately 1% of the population. First-line treatment for epilepsy is the administration of anti-seizure medication, also referred to as antiepileptic drugs (AEDs), although this nomenclature is erroneous as these medications typically do not impact underlying epileptogenic processes; the goal of these medications is to control symptoms. Over 30% of patients are classified as having "medically refractory" epilepsy, i.e., lack of adequate seizure control despite trials of two or three AEDs (Kwan and Brodie, N Engl J Med 342:314-9, 2000). Epilepsy is associated with worse quality of life in children, adolescents, and their families (Cianchetti et al., Seizure 24:93-101, 2015). Patients with epilepsy have a two to three times greater risk of death than the general population, by various causes including sudden unexplained death in epilepsy patients (SUDEP) (Abdel-Mannan et al., Epilepsy Behav 90:99-106, 2019). It is these factors, among others, that have motivated the continued development of AEDs. This chapter will review the history and evolution of AED development, features of specific AEDs with a focus on the newest generation, and examples of AEDs in development.

Safety, tolerability and effectiveness of transition to eslicarbazepine acetate from carbamazepine or oxcarbazepine in clinical practice

PURPOSE

To assess the efficacy, safety and tolerability of eslicarbazepine acetate (ESL) in patients transitioning from carbamazepine or oxcarbazepine to ESL in clinical practice, by analysing data from the Euro-Esli study.

METHODS

Euro-Esli was a pooled analysis of 14 European clinical practice studies. Effectiveness assessments included responder rate (≥50 % seizure frequency reduction) and seizure freedom rate (seizure freedom at least since prior visit), assessed after 3, 6 and 12 months of ESL treatment, and at the last visit. Safety and tolerability were assessed throughout follow-up by evaluating adverse events (AEs) and ESL discontinuation due to AEs, respectively. Data were analysed for cohorts of patients who transitioned from carbamazepine and oxcarbazepine to ESL either due to lack of efficacy or poor tolerability.

RESULTS

Euro-Esli included 2058 patients, of whom 233 (11.3 %) transitioned from carbamazepine to ESL and 134 (6.5 %) transitioned from oxcarbazepine to ESL. After 12 months of ESL treatment, responder and seizure freedom rates for patients transitioning from carbamazepine due to lack of efficacy (n = 163) were 70.0 % and 30.9 %, respectively. Corresponding values for patients transitioning from oxcarbazepine due to lack of efficacy (n = 90) were 57.1 % and 25.0 %, respectively. Among patients who transitioned from carbamazepine and oxcarbazepine to ESL due to poor tolerability (n = 64 and n = 61, respectively), 26.6 % and 39.5 % experienced AEs, and 8.3 % and 6.8 % discontinued ESL due to AEs, respectively.

CONCLUSION

ESL was efficacious and generally well tolerated in patients transitioning from carbamazepine or oxcarbazepine in clinical practice due to inadequate seizure control or intolerable AEs with these agents.

Serum sodium levels and related treatment-emergent adverse events during eslicarbazepine acetate use in adults with epilepsy

Objective

To examine the frequency of hyponatremia and potentially related symptoms in clinical trials of eslicarbazepine acetate (ESL) in adults with focal‐ (partial‐) onset seizures.

Methods

This post hoc, exploratory analysis included data from three controlled phase 3 trials of adjunctive ESL (400‐1200 mg once daily), two phase 3 trials of ESL monotherapy (1200‐1600 mg once daily), and their open‐label extension studies. Exploratory endpoints included clinical laboratory measurements of serum sodium concentrations ([Na⁺]), incidences of hyponatremia‐related treatment‐emergent adverse events (TEAEs), and incidences of TEAEs that are potential symptoms of hyponatremia.

Results

The controlled trials of adjunctive ESL and ESL monotherapy included 1447 (placebo, n = 426; ESL, n = 1021) and 365 (ESL, n = 365) patients, respectively; 639 and 274 patients continued onto uncontrolled, open‐label extensions. In the controlled and uncontrolled trials ≤3.3% of patients taking ESL had a minimum postdose [Na⁺] measurement ≤125 mEq/L, <9% had a >10 mEq/L decrease in [Na⁺] from baseline, <6% had a hyponatremia‐related TEAE, and <2% discontinued the controlled trials due to a hyponatremia‐related TEAE. Hyponatremia appeared to be more frequent in the monotherapy (vs adjunctive therapy) trials; in the controlled trials of adjunctive ESL and ESL monotherapy, incidence generally increased with increasing ESL dose. The majority of patients with an investigator‐reported TEAE of “hyponatremia” or “blood sodium decreased” did not have a corresponding laboratory [Na⁺] measurement ≤125 mEq/L. Some symptoms potentially related to hyponatremia (including nausea and vomiting) were more frequent in patients with a minimum postdose [Na⁺] measurement ≤125 mEq/L.

Significance

Reductions in serum sodium concentrations and hyponatremia‐related TEAEs occurred in a small number of patients taking ESL. Suspected hyponatremia should be confirmed and monitored via [Na⁺] measurements.

Comparative neuropsychological effects of carbamazepine and eslicarbazepine acetate

People with epilepsy are at increased risk for neuropsychological dysfunction due to multiple factors, of which the most amendable are antiseizure medications (ASMs). Antiseizure medication effectiveness is frequently determined by tolerability. In this study, we compared the neuropsychological effects of eslicarbazepine acetate (ESL) and carbamazepine immediate-release (CBZ) using a randomized, double-blind, crossover design in healthy volunteers with a 2-week titration and 4-week maintenance phase in each treatment arm (CBZ = 400 mg BID and ESL = 800 mg qAM). Neuropsychological testing was performed at the initial visit, repeated at 1st baseline nondrug condition, end treatment #1, 2nd nondrug condition one month after treatment #1, end treatment #2, and 3rd nondrug condition one month after treatment #2. Neuropsychological testing was conducted 2 h after morning dose and included computer (i.e., dual task test, selective attention test, symbol digit, verbal memory, visuospatial memory, and 1- & 2-back continuous performance) and noncomputer tasks (i.e., Medical College of Georgia (MCG) paragraph memory, Stroop, Symbol Digit Modalities Test, Profile of Mood States). z-Scores calculated from nondrug conditions were used to compare ESL and CBZ for the 23 completers. Follow-up analyses included individual test scores and distribution of individual raw means. Mean blood levels on test day were CBZ = 8.9 μg/ml and ESL = 15.3 μg/ml. Omnibus z-score was significantly better for ESL (p = .0001). For individual measures, executive function and selective attention tests were statistically significantly better for ESL. Individual test raw means favored ESL over CBZ on 22 of 30 measures (p = .016, 2-tailed sign test). Eslicarbazepine acetate demonstrated less adverse neuropsychological effects than CBZ.

Long-term safety and efficacy following conversion to eslicarbazepine acetate monotherapy in adults with focal seizures

OBJECTIVE

To assess the long-term safety and efficacy of eslicarbazepine acetate (ESL) monotherapy in adults with focal seizures (FS).

METHODS

Study 050 was a long-term, multicenter, open-label (OL) safety extension of two conversion-to-ESL monotherapy studies in adults with refractory FS. After participating in Study 045 or 046, patients started on ESL 1600 mg once daily (QD) (or 1200 mg if they previously had a dose reduction), and could adjust the dose 400 mg/week to a dose between 800-2400 mg QD. Patients could add up to two additional antiepileptic drugs (AEDs). This post-hoc analysis focuses on the actual monotherapy subgroup, which included patients in Studies 045/046/050 who did not add additional AEDs. Study endpoints included treatment retention time, time on ESL monotherapy, change in standardized seizure frequency (SSF), change in quality of life (QoL) in epilepsy (QOLIE-31) and Montgomery-Åsberg Depression Rating Scale (MADRS) scores, and incidence of treatment-emergent adverse events (TEAEs); serious adverse events (SAEs), TEAEs leading to discontinuation, and TEAEs related to allergic reaction, hyponatremia and thyroid function were also evaluated.

RESULTS

There were 274 patients in the Study 050 full intent-to-treat (ITT) population and 140 patients in the actual monotherapy subgroup. Median treatment retention time and time on ESL monotherapy were both >5 years. Median reduction in SSF from baseline was 66.4% in the full ITT population and 78.3% in the actual monotherapy subgroup; responder (≥50% reduction in SSF) rates were 62.4% and 74.3%, respectively. QOLIE-31 scores increased from baseline in the full ITT population and the actual monotherapy subgroup (4.1- and 7.5-point increases, respectively). MADRS scores decreased from baseline in both the full ITT population and the actual monotherapy subgroup (0.7- and 2.9-point decreases, respectively). TEAEs occurred in 85.4% of patients in the full ITT population and 81.4% of patients in the actual monotherapy subgroup. Incidences of SAEs and TEAEs leading to discontinuation, as well as dizziness, depression, fall, partial seizures with secondary generalization, and complex partial seizures, were higher in the full ITT population than in the actual monotherapy subgroup. Allergic reactions, hyponatremia, and hypothyroidism were infrequent, particularly in the actual monotherapy subgroup.

CONCLUSIONS

The results of this post-hoc analysis suggest that long-term treatment with ESL was effective and well tolerated, both as a monotherapy and in combination with other AEDs for FS. QoL and tolerability appeared to be better, and incidence of depression lower, in the patient population taking ESL as a monotherapy, compared with the population that included patients taking ESL as an adjunctive therapy.

Health-related quality of life in patients treated with eslicarbazepine acetate monotherapy: Pooled analysis from two registered clinical trials

PURPOSE

While antiepileptic drug (AED) treatment effectiveness is traditionally assessed based on seizure frequency reduction (SFR), the overall value of AEDs in managing epilepsy and associated sequelae may be best assessed by how patients feel and function in terms of overall health-related quality of life (HRQoL). We conducted a pooled analysis of the Quality of Life in Epilepsy-31 (QOLIE-31) questionnaire from two phase 3 trials to explore the effect of response to conversion to eslicarbazepine acetate (ESL) monotherapy on HRQoL.

METHODS

Data were pooled from two multicenter, randomized, double-blind, historical control phase 3 trials examining conversion to ESL monotherapy in adults with inadequately controlled partial-onset seizures (POS). The relationship between HRQoL and ESL treatment response was examined through the analysis of week 18 QOLIE-31 scores between patients who met the SFR ≥50% threshold (responders) and patients with SFR <50% (nonresponders). The analysis was conducted in the efficacy population (intent-to-treat (ITT) patients who entered the AED taper/conversion period) and completer population (efficacy patients who completed the ESL monotherapy period) and was repeated using an SFR ≥75% threshold.

RESULTS

In the efficacy population, week 18 QOLIE-31 total score least squares mean (LSM) was significantly higher for responders with ≥50% SFR (LSM difference: 3.0; 95% confidence interval (CI): 0.2-5.8; p = 0.037) and with ≥75% SFR (LSM difference: 7.0; 95% CI: 3.6-10.3; p < 0.001) than nonresponders. In the completer population, overall quality of life (QoL) (LSM difference: 5.1; 95% CI: 1.5-8.6; p = 0.006) and social functioning (LSM difference: 5.4; 95% CI: 0.1-10.7; p = 0.046) were significantly higher for responders with ≥50% SFR than nonresponders, and all domain LSMs were higher for responders with ≥75% SFR (all p < 0.05) than nonresponders.

CONCLUSIONS

This analysis of data from the phase 3 trials demonstrated significantly higher HRQoL among ESL responders with SFR of ≥75% and also at the lower SFR threshold of ≥50% compared with nonresponders.

Variability in expression of the human MDR1 drug efflux transporter and genetic variation of the ABCB1 gene: implications for drug-resistant epilepsy

Among individuals diagnosed with epilepsy, as many as one in three develop resistance to antiepileptic drugs (AEDs) thus rendering their seizures refractory to treatment. Despite current antiepileptic drugs (AEDs) having a variety of modes of action, seizures in drug-resistant individuals often persist even after treatment with two or more drugs. The underlying cause of this broad resistance is currently under debate, but two dominant theories have emerged and have been widely studied. Here we discuss current literature investigating the "transporter theory", the idea that individuals present with drug resistance due to genetic variability in the ABCB1 gene encoding the efflux transporter multidrug resistance protein 1 (MDR1). Results of in vitro and in vivo studies suggest that variability in the expression of the MDR1 transporter may be closely tied to drug resistance. While there is much support for this hypothesis from molecular and mechanistic studies, population-based studies of ABCB1 polymorphisms are divergent in their conclusions, and there is need for additional investigations.