Greater need for treatment optimization in patients with epilepsy initiating adjunctive therapy: Results of a retrospective claims analysis of antiseizure medication drug load in the United States

BACKGROUND

This retrospective, observational study used US claims data to assess changes in antiseizure medication (ASM) drug load for a cohort of patients with epilepsy.

METHODS

Adults (≥18 years) with a diagnosis of epilepsy (ICD-10 code G40.xxx) who started new adjunctive ASM treatment with one of 4 branded (brivaracetam, eslicarbazepine, lacosamide, perampanel) or 4 unbranded (carbamazepine, lamotrigine, levetiracetam, topiramate) ASMs between January 1, 2016 and December 31, 2020 were identified from IBM MarketScan® research databases (primary study population). Patients must have been continuously enrolled 360 days before the start of the new ASM (eligibility period). Follow-up was from the start of new ASM until Day 540 (∼18 months). The primary endpoint was concomitant ASM drug load, which included all ASMs except the new (comparator) ASM. A sensitivity analysis population included adults with epilepsy who were continuously enrolled for ≥ 180 days during at least one calendar year in the study period (2016-2020), whether or not the comparator ASM was new or existing during that period. Total ASM drug load, which included comparator ASM and concomitant ASMs, was assessed in the sensitivity analysis population.

RESULTS

In total, 21,332 patients were included in the primary study population, of which 5767 initiated branded ASMs and 15,565 initiated unbranded ASMs. A total of 392,426 patients were included in the sensitivity analysis population during at least one calendar year 2016-2020. Concomitant ASM drug load increased in the 360 days prior to new ASM start and slightly declined thereafter. Mean concomitant ASM drug load for the primary population was 1.6 (SD 1.8) at new ASM start. Concomitant drug load was higher among those starting branded ASM comparators compared to those starting unbranded comparators. Mean total ASM drug load for patients increased over time and was approximately double for patients exposed to branded ASMs (mean range 2.1 to 2.7) compared to that of patients exposed to any unbranded ASM (mean range 1.0 to 1.3).

CONCLUSION

Concomitant ASM drug load increased prior to addition of new ASM, with higher increases observed among patients starting branded vs unbranded ASMs, followed by slight decreases thereafter. Total drug load increased linearly among all patients. These findings underscore the need for ongoing ASM regimen evaluation and treatment optimization in patients with epilepsy.

Imperatorin interacts additively with novel antiseizure medications in the mouse maximal electroshock-induced seizure model: an isobolographic transformation

BACKGROUND

Anticonvulsant effects of imperatorin (IMP) have been experimentally confirmed earlier, but no information is available on the interaction profiles of this naturally occurring coumarin when combined with novel antiseizure medication (ASMs). This study aimed to determine the effects of IMP on the anticonvulsant effects of lacosamide (LCM), oxcarbazepine (OXC), pregabalin (PGB), and topiramate (TPM) in the maximal electroshock-induced seizure (MES) model in mice.

METHODS

The anticonvulsant effects exerted by novel ASMs (LCM, OXC, PGB, and TPM) when combined with constant doses of IMP (25 and 50 mg/kg) underwent isobolographic transformation to precisely classify the observed interactions in the mouse MES model. Total brain concentrations of ASMs were measured with high-pressure liquid chromatography to exclude the pharmacokinetic nature of interactions among IMP and the tested ASMs.

RESULTS

IMP (50 mg/kg) significantly enhanced (p < 0.01) the anticonvulsant potency of LCM, OXC, PGB, and TPM in the mouse MES model. IMP (25 mg/kg) mildly potentiated the anticonvulsant action of LCM, OXC, PGB, and TPM, but no statistical significance was reported for these combinations. The isobolographic transformation of data from the MES test revealed that the interactions of novel ASMs with IMP were additive. Moreover, IMP (50 mg/kg) did not affect the total brain content of any of the novel ASMs in experimental mice.

CONCLUSIONS

The additive interactions of IMP with LCM, OXC, PGB, and TPM in the mouse MES model accompanied by no pharmacokinetic changes in the total brain content of ASMs are worthy of recommendation for further studies.

Case 321: Leigh Syndrome

HISTORY

A 9-month-old preterm male infant born at 33 weeks gestation presented with a 2-month history of developmental decline. The parents reported that over the past several months, they noted regression of milestones, where the infant stopped smiling, crying, expressing himself, or making eye contact. The parents also reported that the infant had multiple seizures during which he would wake up stiff and stare into space for 10-20 seconds while his lips would become blue. The parents were referred to a neurologist, where physical examination was notable for hypotonia. Electroencephalography (EEG) revealed frequent bilateral parietal epileptiform discharges. The patient was subsequently started on lacosamide. The patient's medical history was notable for abnormally low citrulline levels at birth, with negative results of urea cycle disorder testing at the time, along with left inguinal hernia repair performed 3 months ago. More recent laboratory analysis had shown persistently elevated serum lactate and alanine levels. There was no history of travel, recent infection, or vaccine administration. MRI of the brain with spectroscopy was performed for further evaluation.

Therapeutic monitoring of lacosamide, perampanel, and zonisamide during breastfeeding

OBJECTIVE

To provide additional information on the transport of the new anti-seizure medications lacosamide, perampanel, and zonisamide in breast milk and breastfed infants.

METHODS

Between 2013 and 2022, concentrations of anti-seizure medications were measured in six women with epilepsy (each drug in two patients) using high-performance liquid chromatography. Additionally, concentrations were determined after two consecutive pregnancies in women receiving lacosamide and one woman receiving zonisamide. In all cases, anti-seizure medication concentrations were measured in the maternal serum and breast milk, and five cases, in the infant serum.

RESULTS

For lacosamide, the ratios of breast milk/maternal serum concentration varied between 0.77 and 0.93, the ratios of infant/maternal serum concentrations were 0.16 and 0.35, and the ratios of infant serum/milk concentrations were 0.21 and 0.38. For perampanel, the ratios of breast milk/maternal serum concentration were 0.01 and 0.10 and the ratio of infant/maternal serum concentration was 0.36. For zonisamide, the ratios of breast milk/maternal serum concentration varied between 0.76 and 1.26, the ratios of infant/maternal serum concentrations between 0.44 and 0.85, and the ratios of infant serum/milk concentrations between 0.55 and 1.05.

CONCLUSIONS

Breastfeeding is recommended for women using lacosamide, perampanel, and zonisamide. However, the actual exposure can only be accurately evaluated by determining the serum concentration of anti-seizure medication in breastfed infants.

Quantification of Gabapentin, Lacosamide, Perampanel, Pregabalin, Rufinamide, and Vigabatrin in Serum Using Liquid Chromatography-Tandem Mass Spectrometry

Antiepileptic drugs (AEDs) have been used to control epilepsy. More than 17 new AEDs, including gabapentin (GPN), lacosamide (LCM), perampanel (PER), pregabalin (PRG), rufinamide (RFM), and vigabatrin (VGB) have been approved and marketed since 1989. Accurate measurement of serum concentration of the antiepileptic drugs is crucial to achieve optimal efficacy and avoid adverse events. We describe an accurate and precise liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of GPN, LCM, PER, PRG, RFM, and VGB in serum. The method requires a small volume of sample (10 μL) and has a total chromatographic run time of 4 min for simultaneous measurement of these drugs. The method showed good accuracy with a bias of -0.2-5%. The intra- and inter-day imprecision were less than 5.0% for all the analytes. The linear assay ranges were 0.3-26 μg/mL for GPN, 0.15-24 μg/mL for LCM, 7.4-1881 ng/mL for PER, 0.03-13 μg/mL for PRG, 0.78-90 μg/mL for RFM, and 0.3-43 μg/mL for VGB.

Development and Validation of Stability-Indicating High-Performance Liquid Chromatography Method for Estimation of Lacosamide in Bulk and Its Pharmaceutical Dosage Form

A simple, specific, accurate and stability-indicating reversed-phase high-performance liquid chromatographic method was developed for the determination of lacosamide, using C18 column and a mobile phase composed of phosphate buffer (pH 4.0):acetonitrile (40:60 v/v). The retention time of lacosamide was found to be 2.7 min. Linearity was established for lacosamide in the range of 10-50 μg/mL. The percentage recovery of lacosamide was found to be in the range of 97.37-99.20%. The drug was subjected to acid, alkali, oxidation, dry heat and photolytic degradation. The degradation studies indicated condition was well resolved from the pure drug with significant differences in their retention time values. This method can be successfully employed for quantitative analysis of lacosamide in bulk drug and formulation.

The effect of plasma exchange on serum levels of lacosamide: A case report

PURPOSE

We describe the case of a 22-year-old male who developed thyroid storm necessitating therapeutic plasma exchange (TPE). The patient's past medical history was complicated by epilepsy, for which he took lacosamide. Little evidence was available to guide lacosamide dosing during TPE. Because of an exacerbation of the patient's underlying epilepsy in the context of the thyroid storm, we conducted therapeutic medication monitoring of lacosamide concentrations to guide management.

SUMMARY

We arranged for measurement of the lacosamide concentration immediately before TPE (5.1 μg/mL) and 2.5 hours after the initial measurement (3.4 μg/mL) to determine the amount of lacosamide removed by TPE. Utilizing population pharmacokinetic parameters, we calculated the expected concentration and compared this to the measured concentration. The difference between these values was used to determine the percentage removed via TPE compared to the expected post-TPE concentration. We found that one TPE session removed an additional 20% of serum lacosamide.

CONCLUSION

TPE appeared to remove an additional 20% of lacosamide when compared to the expected post-TPE concentration.

[Analysis of the efficacy and influencing factors of sodium channel blockers in the treatment of focal epilepsy in infants under 6 months of age]

Objective: To analyze the efficacy and safety of the sodium channel blockers (SCB) antiseizure medication in the treatment of focal epilepsy in infants under 6 months of age. Methods: This was a case series study. Infants with focal epilepsy with onset within 6 months of age and treated with SCB attending the Department of Neurology of Beijing Children's Hospital from June 2016 to April 2022 were collected. The clinical data, auxiliary examinations, SCB application, efficacy, adverse reactions, and prognosis were analyzed retrospectively. Patients were grouped according to type of seizure and epileptic syndrome, age of onset and etiology. Chi square test and Fisher exact test were used to analyze the differences between groups statistically. Results: A total of 118 infants were enrolled, 65 males and 53 females, with an age of epilepsy onset of 56 (4, 114) days. Developmental and epileptic encephalopathy was diagnosed in 60 infants, 39 had self-limited neonatal and (or) infantile epilepsy, and 19 had non-syndromic focal epilepsy. Application of SCB: 106 used oxcarbazepine, 2 used lacosamide, 9 switched from oxcarbazepine to lacosamide or a combination of 2 SCB, and 1 used oxcarbazepine, lacosamide, and lamotrigine successively; oxcarbazepine was the first choice in 46 cases. The age at which SCB was applied was 103 (53, 144) days. The children were followed up for 6 months to 6 years. SCB was effective in 89 cases (75.4%), including 70 cases (59.3%) who achieved seizure freedom. The seizure-free rate was higher in the focal epilepsy only group than in the group with other seizure types (64.4% (65/101) vs. 4/17, χ²=9.99, P<0.05). The responder and seizure-free rates were all higher in the group with the onset age of >3-6 months than the group >1-3 months (84.4% (38/45) vs. 62.5% (20/32), 73.3% (33/45) vs. 46.9% (15/32), χ²=4.85 and 5.58, both P<0.05). With the exception of variants in the PRRT2 gene, those with variants in sodium or potassium channels had higher responder and seizure-free rates than those with variants in other genes(86.2% (25/29) vs. 45.5% (10/22), 62.1% (18/29) vs. 22.7% (5/22), χ²=9.65 and 7.82,both P<0.05). The most common adverse event was transient hyponatremia, which happened in 66 cases (55.9%). There were 9 cases of rash, which subsided in 6 cases after discontinuing oxcarbazepine and switching to lacosamide, and 7 cases of electrocardiogram abnormalities, which improved after withdrawing oxcarbazepine and changing to lacosamide in 1 case. Conclusion: SCB are effective and tolerable in the treatment of focal epilepsy in infants under 6 months of age, with better efficacy in patients with genetic variants of the sodium or potassium channel, focal seizures only, and seizure onset >3-6 months of age.

Real-world analysis of retention on cenobamate in patients with epilepsy in the United States

BACKGROUND

This retrospective, observational study used US claims data to assess retention rates on cenobamate compared with four branded antiseizure medications (ASMs) in patients with epilepsy.

METHODS

Adults (≥18 years) with prevalent epilepsy (ICD-10 code G40.xx) and ≥ 1 prescription for cenobamate or any of the newer branded ASMs (brivaracetam, eslicarbazepine, lacosamide, or perampanel) between May 1, 2020 and December 31, 2021 were identified from the HealthVerity Marketplace database. At least 360 days of continuous enrollment was required before and after the index date (Day 1 of initiating cenobamate or branded ASM). Patients were followed until cessation of cenobamate or branded ASM or the end of data collection using Kaplan-Meier methods. Retention was compared between cenobamate and the branded ASMs (both as a group and individually) using Chi-square tests.

RESULTS

In total, 4109 patients were included (195 cenobamate; 3914 branded ASMs). A higher proportion of patients in the cenobamate group compared with the branded ASMs group had concurrent focal and generalized epilepsy (65.6% vs 40.0%) and were on ≥ 3 concomitant ASMs (48.2% vs 12.8%) at the index date. Median time to discontinuation (i.e., the time that half the patients discontinued) was not quite reached after 12 months in the cenobamate group (50.3% of patients remained on cenobamate) and was 7.7 months in the branded ASMs group. Retention was significantly higher with cenobamate vs the branded ASMs group (p = 0.04545) and vs the individual ASMs lacosamide (p = 0.03044) and perampanel (p = 0.01558). Twelve-month retention rates (95% confidence intervals) were 50.3% (43.1%-57.0%) for cenobamate, 40.5% (38.9%-42.0%) for branded ASMs overall, 42.3% (38.6%-46.0%) for brivaracetam, 44.1% (39.2%-49.0%) for eslicarbazepine, 39.9% (38.0%-41.8%) for lacosamide, and 36.8% (31.9%-41.8%) for perampanel.

CONCLUSIONS

In this real-world analysis, retention was significantly higher with cenobamate vs a pooled group of four branded ASMs despite a greater frequency of patients in the cenobamate group having characteristics of more difficult-to-treat epilepsy.

Efficacy and tolerability of lacosamide and controlled-release carbamazepine monotherapy in patients with newly diagnosed temporal lobe epilepsy: Post hoc analysis of a randomized, double-blind trial

PURPOSE

Temporal lobe epilepsy (TLE) is often associated with drug-resistant seizures. We evaluated the efficacy and tolerability of lacosamide (LCM) versus controlled-release carbamazepine (CBZ-CR) monotherapy in adults with newly diagnosed TLE.

METHODS

Exploratory post hoc analysis of patients with temporal focus of localization (indicated as the only localization focus) in a double-blind, noninferiority, phase 3 trial (SP0993; NCT01243177) in patients aged ≥ 16 years with newly diagnosed epilepsy randomized 1:1 to LCM or CBZ-CR monotherapy.

RESULTS

Of 886 treated patients in this trial, temporal lobe focus of localization (TLE) was reported as the single focus for 287 (32.4%) patients (LCM 134, CBZ-CR 153). A similar proportion of patients with TLE on LCM (82  [61.2%]) and CBZ-CR (99  [64.7%]) completed the trial. Kaplan-Meier estimates for 6- and 12-month seizure freedom at the last evaluated dose level (stratified by number of seizures in the 3 months before screening  [≤2 or >2 seizures]) were similar with LCM and CBZ-CR (6 months overall: 88.7% and 89.7%; 12 months overall: 78.3% and 81.7%). Treatment-emergent adverse events (TEAEs) were reported by fewer patients on LCM (73.9%) than CBZ-CR (81.0%). Drug-related TEAEs (assessed by the investigator) were reported in 41.8% of patients on LCM and 52.3% of patients on CBZ-CR; 11.2% of patients on LCM and 15.0% on CBZ-CR discontinued due to TEAEs.

CONCLUSION

Lacosamide was efficacious and generally well tolerated as monotherapy in patients with TLE with efficacy outcomes comparable with CBZ-CR, and fewer patients on LCM reported any TEAEs, drug-related TEAEs, or discontinued due to TEAEs.

Effect of Lacosamide on Interictal Epileptiform Discharges in Pediatric Patients With Newly Diagnosed Focal Epilepsy

BACKGROUND

The purpose of this study was to determine the efficacy of lacosamide (LCM) on interictal epileptiform discharges (IEDs) and evaluate the relationships between IEDs and seizure outcome in pediatric patients with focal epilepsy.

METHODS

Patient inclusion criteria included (1) newly diagnosed focal epilepsy with unknown etiology; and (2) electroencephalogram recorded twice (before and after starting LCM) under the same conditions. The difference between the highest number of IEDs over five successive minutes (IEDs/5 min) and the location of IEDs was determined. Seizure outcome was evaluated one year after achieving the maintenance dose of LCM. Responders were identified as showing a ≥50% reduction in the pre-LCM seizure frequency.

RESULTS

Of 22 patients, 10 showed an increase in IEDs/5 min after starting LCM. The median IEDs/5 min before and after starting LCM was not significantly different, at 1.5 (interquartile range: 0, 31.75) and 10.5 (0, 80.5), respectively. No relationship was identified between the difference in IEDs/5 min and seizure outcome. Patients with multiple regional or diffuse IEDs had significantly poorer seizure outcome compared with patients without those IEDs (P = 0.036 and P = 0.039, respectively). Of 10 patients with single regional IEDs, a tendency of IEDs to disappear was observed between patients with frontal and non-frontal IEDs.

CONCLUSION

The effects of LCM on the number of IEDs may be unrelated to seizure outcome. LCM may be ineffective at improving seizure outcomes in patients with multiple regional or diffuse IEDs.

Safety of intravenous lacosamide in hospitalized children and neonates

OBJECTIVE

Seizures are common in critically ill children and neonates, and these patients would benefit from intravenous (IV) antiseizure medications with few adverse effects. We aimed to assess the safety profile of IV lacosamide (LCM) among children and neonates.

METHODS

This retrospective multicenter cohort study examined the safety of IV LCM use in 686 children and 28 neonates who received care between January 2009 and February 2020.

RESULTS

Adverse events (AEs) were attributed to LCM in only 1.5% (10 of 686) of children, including rash (n = 3, .4%), somnolence (n = 2, .3%), and bradycardia, prolonged QT interval, pancreatitis, vomiting, and nystagmus (n = 1, .1% each). There were no AEs attributed to LCM in the neonates. Across all 714 pediatric patients, treatment-emergent AEs occurring in >1% of patients included rash, bradycardia, somnolence, tachycardia, vomiting, feeling agitated, cardiac arrest, tachyarrhythmia, low blood pressure, hypertension, decreased appetite, diarrhea, delirium, and gait disturbance. There were no reports of PR interval prolongation or severe cutaneous adverse reactions. When comparing children who received a recommended versus a higher than recommended initial dose of IV LCM, there was a twofold increase in the risk of rash in the higher dose cohort (adjusted incidence rate ratio = 2.11, 95% confidence interval = 1.02-4.38).

SIGNIFICANCE

This large observational study provides novel evidence demonstrating the tolerability of IV LCM in children and neonates.

Stability-indicating normal-phase HPLC method development for separation and quantitative estimation of S-enantiomer of lacosamide in pharmaceutical drug substance and tablet dosage form

Lacosamide (LA) is an antiepileptic medicine that is used to treat tonic-clonic seizures, partial-onset seizures, mental problems, and pain. A simple, effective, and reliable normal-phase liquid chromatographic technique was developed and validated to separate and estimate the enantiomer of (S-enantiomer) LA in pharmaceutical drug substance and drug product. Normal-phase LC was performed using USP L40 packing material (250 × 4.6 mm, 5 μm) and a mobile phase of n-hexane and ethanol at 1.0 ml min-1 . The detection wavelength, column temperature, and injection volume used were 210 nm, 25°C, and 20 μl, respectively. The enantiomers (LA and S-enantiomer) were completely separated using a minimum resolution of 5.8 and accurately quantified without any interference in a 25-min run time. Accuracy study for stereoselective and enantiomeric purity trials was conducted between 10 and 200%, with recovery values ranging from 99.4 to 103.1% and linear regression values >0.997. The stability-indicating characteristics were assessed using forced degradation tests. The proposed normal-phase HPLC technique is an alternate approach to the official monograph methods (USP and Ph.Eur.) of LA, and it was successfully used in the evaluation of release and stability samples for both tablet dosage forms and pharmaceutical substances.

Differential Pharmacokinetic Interplay of Atorvastatin on Lacosamide and Levetiracetam on Experimental Convulsions in Mice

BACKGROUND

The beneficial effects of statins, other than their hypocholesterolemia role, have been well documented, however, their use as an adjuvant drug with other antiseizure drugs, in the treatment of epilepsy is poorly understood.

OBJECTIVE

This study aimed to investigate the symbiotic effect of ATOR along with either lacosamide (LACO) or levetiracetam (LEVE) on experimentally induced epilepsy (Maximal electro-shock-MES or pentylenetetrazol- PTZ) in mice models.

METHODS

Conventional elevated-maze (EPM) and rotarod methods were performed to observe the behavioral effects.

RESULTS

In both the animal models, we found that co-administration of ATOR along with LACO showed a significant reduction in hind-limb extension (HLE) and clonic convulsion (CC) responses, respectively, but not in the ATOR+LEVE treated group. Intriguingly, comparable Straub tail response and myoclonic convulsion as the diazepam (DIA) group were observed only in the ATOR+LACO treated group. Moreover, a significant muscle-grip strength was observed in both groups. Also, pharmacokinetic analysis has indicated that the mean plasma concentration of ATOR peaked at 2nd hr in the presence of LACO but marginally peaked in the presence of LEVE. An Insilico study has revealed that ATOR has a higher binding affinity toward neuronal sodium channels.

CONCLUSION

This study has demonstrated that the plasma concentration of ATOR was potentiated in the presence of LACO, but not in the presence of LEVE and it has provided significant protection against both the electro and chemo-convulsive models in mice. This could be due to the symbiotic pharmacokinetic interplay of ATOR with LACO, and possibly, this interplay may interfere with sodium channel conductance.

Changes in the Use of Brand Name and Generic Medications and Total Prescription Cost Among Medicare Beneficiaries With Epilepsy

BACKGROUND AND OBJECTIVE

To characterize trends in antiseizure medication (ASM) fills and total prescription costs in people with epilepsy.

METHODS

This was a retrospective cohort study of beneficiaries with epilepsy (ASM, plus ICD codes) in a 20% random Medicare sample, with continuous Fee-For-Service coverage (Parts A, B, and D) in 2008-2018. We summed the number of pill days and costs (adjusted to 2018 dollars) per person-year for each ASM. ASMs were categorized into brand vs generic, first vs newer generation, and enzyme inducers vs noninducers.

RESULTS

There were 77,000-133,000 beneficiaries with epilepsy per year. The most common ASM was phenytoin in 2008, which shifted to levetiracetam in 2018 (2008: phenytoin 25%, levetiracetam 14%; 2018: phenytoin 9%, levetiracetam 27%). Brand name (2008: 56%; 2018: 14%), first-generation (2008: 55%; 2018: 32%), and enzyme-inducing ASMs (2008: 44%; 2018: 24%) each decreased over time as a proportion of pill days. The number of brand pill days per person-year initially decreased (e.g., 2008: 250; 2009: 121; 2010: 96) but then plateaued (2013-2018: between 66 and 69) given a notable increase in lacosamide pill days per person (2008: 0; 2018: 20). Total brand name costs per year initially decreased 2008-2010 (2008: $150 million; 2010: $72 million) but then increased after 2010 (2018: $256 million). In 2018, brand name ASMs represented 79% of costs despite representing only 14% of pill days, a 1-year pill supply became 277% more expensive for brand name medications but 42% less expensive for generic medications over time (2008: brand ∼$2,800 vs generic ∼$800; 2018: brand ∼$10,700 vs generic ∼$460), and many common brand name ASMs cost approximately 10-fold more per pill day than their generic equivalents.

DISCUSSION

First-generation and enzyme-inducing ASMs waned from 2008 to 2018. Although brand name ASMs initially waned translating into lower costs and potentially higher value care, after 2010, brand name costs markedly increased because of increasing use of lacosamide plus a 277% increase in per-pill cost of brand name ASMs. Brand name ASMs represented a minority of prescriptions, but the majority of costs.

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.

Management of corticosteroid-dependent eosinophilic interstitial nephritis: A case report

INTRODUCTION

Drug-induced acute interstitial nephritis (DI-AIN) is an important cause of acute kidney injury. In renal biopsy specimens, tubulitis with eosinophilic infiltration is suggestive of DI-AIN. Although corticosteroid therapy and discontinuation of the offending drug can improve renal dysfunction in most cases of DI-AIN, some patients experience AIN recurrence, leading to corticosteroid dependency. Corticosteroid-dependent eosinophilic interstitial nephritis presents a difficult dilemma in diagnosis and information regarding optimum management is limited.

PATIENT CONCERNS

A 25-year-old man, who received treatment with carbamazepine, zonisamide, valproate, and lacosamide for temporal lobe epilepsy, showed an increase in serum creatinine level from 0.98 to 1.29 mg/dL over a period of 6 months. Although he exhibited no symptoms, his serum creatinine level continued to increase to 1.74 mg/dL.

DIAGNOSIS

Renal biopsy revealed tubulitis and interstitial inflammatory infiltrates with eosinophils. Immunological and ophthalmological examinations showed no abnormal findings, and thus, his renal dysfunction was presumed to be caused by DI-AIN. Although oral prednisolone (PSL) administration (40 mg/d) and discontinuation of zonisamide immediately improved his renal function, AIN recurred 10 months later. The increase in PSL dose along with discontinuation of valproate and lacosamide improved renal function. However, 10 months later, recurrent AIN with eosinophilic infiltration was confirmed by further biopsy. The patient was therefore diagnosed with corticosteroid-dependent eosinophilic interstitial nephritis.

INTERVENTIONS

To prevent life-threatening epilepsy, carbamazepine could not be discontinued; hence, he was treated with an increased dose of PSL (60 mg/d) and 1500 mg/d of mycophenolate mofetil (MMF).

OUTCOMES

MMF was well tolerated and PSL was successfully tapered to 5 mg/d; renal function stabilized over a 20-month period.

LESSONS

The presence of underdetermined autoimmune processes and difficulties in discontinuing the putative offending drug discontinuation are contributing factors to corticosteroid dependency in patients with eosinophilic interstitial nephritis. MMF may be beneficial in the management of corticosteroid-dependent eosinophilic interstitial nephritis by reducing the adverse effects related to high-dose and long-term corticosteroid use.

Long-term retention rates of antiepileptic drugs used in acute seizures

PURPOSE

A number of antiepileptic drugs (AEDs) are currently available for treating acute seizures. It is recommended to select the initial treatment option according to the type of epileptic syndrome and the patient's clinical characteristics, but little is known about the long-term retention rates of AEDs started in the emergency department.

METHODS

We recruited patients admitted with seizures over a two-year period. All patients underwent early neurological assessment, EEG testing, and neuroimaging. The treatments received at baseline and at one year of follow-up were compared.

RESULTS

In total, 225 patients were included. Overall, monotherapy with levetiracetam was the regimen most often used in patients with new-onset seizures, whereas other AEDs were mainly used in patients previously treated with other drugs. Lacosamide use was most likely associated with the presence of lesion related seizures in elderly patients, and carboxamides with focal onset seizures of unknown cause. The mean retention rate of the total of AED treatments was nearly 70%. The main cause leading to discontinuation was the development of intolerable adverse events. Levetiracetam use decreased as lacosamide use increased in the overall group of patients.

CONCLUSION

Our study shows that there is a trend to use newer AEDs, particularly levetiracetam, as the first option in new-onset seizures in the emergency room. However, levetiracetam use significantly decreased over follow-up, mainly because of the development of adverse events. The use of other, better-tolerated AEDs, such lacosamide predominated in elderly patients and patients with lesion related seizures, or carboxamides in epilepsies of unknown etiology.

Mapping protein interactions of sodium channel NaV1.7 using epitope-tagged gene-targeted mice

The voltage-gated sodium channel NaV1.7 plays a critical role in pain pathways. We generated an epitope-tagged NaV1.7 mouse that showed normal pain behaviours to identify channel-interacting proteins. Analysis of NaV1.7 complexes affinity-purified under native conditions by mass spectrometry revealed 267 proteins associated with Nav1.7 in vivo The sodium channel β3 (Scn3b), rather than the β1 subunit, complexes with Nav1.7, and we demonstrate an interaction between collapsing-response mediator protein (Crmp2) and Nav1.7, through which the analgesic drug lacosamide regulates Nav1.7 current density. Novel NaV1.7 protein interactors including membrane-trafficking protein synaptotagmin-2 (Syt2), L-type amino acid transporter 1 (Lat1) and transmembrane P24-trafficking protein 10 (Tmed10) together with Scn3b and Crmp2 were validated by co-immunoprecipitation (Co-IP) from sensory neuron extract. Nav1.7, known to regulate opioid receptor efficacy, interacts with the G protein-regulated inducer of neurite outgrowth (Gprin1), an opioid receptor-binding protein, demonstrating a physical and functional link between Nav1.7 and opioid signalling. Further information on physiological interactions provided with this normal epitope-tagged mouse should provide useful insights into the many functions now associated with the NaV1.7 channel.

Safety of intravenous lacosamide in critically ill children

PURPOSE

Acute seizures are common in critically ill children. These patients would benefit from intravenous anti-seizure medications with few adverse effects. We reviewed the usage and effects of intravenous lacosamide in critically ill children with seizures or status epilepticus.

METHODS

This retrospective series included consecutive patients who received at least one dose of intravenous lacosamide from April 2011 to February 2016 in the pediatric intensive care unit of a quaternary care children's hospital, including patients with new lacosamide initiation and continuation of outpatient oral lacosamide. Dosing and prescribing practices were reviewed. Adverse effects were defined by predefined criteria, and most were evaluated during the full admission.

RESULTS

We identified 51 intensive care unit admissions (47 unique patients) with intravenous lacosamide administration. Lacosamide was utilized as a third or fourth-line anti-seizure medication for acute seizures or status epilepticus in the lacosamide-naïve cohort. One patient experienced bradycardia and one patient experienced a rash that were considered potentially related to lacosamide. No other adverse effects were identified, including no evidence of PR interval prolongation.

CONCLUSIONS

Lacosamide was well tolerated in critically ill children. Further study is warranted to evaluate the effectiveness of earlier lacosamide use for pediatric status epilepticus and acute seizures.

Lacosamide treatment of childhood refractory focal epilepsy: the first reported side effect in paediatric patients

PURPOSE

Lacosamide (LCM) is an effective antiepileptic drug (AED) approved for the treatment of focal epilepsy in both children and adults. The aim of this observational study was to review our centre's experience with LCM and to characterise its efficacy and tolerability as an adjunct therapy in children with refractory focal epilepsy.

METHODS

We retrospectively reviewed the medical records of 12 paediatric patients who underwent treatment with LCM from January 2014 to December 2015. We recorded the treatment response at three time points: at 3 and 6 months after LCM therapy and at the final follow-up visit. Children showing seizure reduction ≥ 50% were considered responders.

RESULTS

We included 12 patients (five boys), and their mean age was 13.8 years (range: 6.2-17.6 years) at the end of LCM treatment. The average length of follow-up after starting LCM was 23 months (11-37 months). Eight patients (66%) had > 50% reduction in seizures at the 3-month follow-up visit, and seven (58%) had > 50% reduction at the 6-month follow-up visit. Six patients (50%) maintained ≥ 50% reduction in seizures at the final follow-up visit. Two patients (16.6%) were seizure free at the 6-month and final follow-up visits. Common adverse side effects included dizziness, ataxia, nausea, and vomiting. Two patients developed status epilepticus (SE), one each at 3 and 11 days after the first LCM dose; they both discontinued treatment.

CONCLUSIONS

Our study points to the efficacy of LCM in a small paediatric group. Furthermore, it was important to report status epilepticus after LCM administration in the paediatric population for the first time.

A case of refractary epilepsy and related pain due to dysmenorrhea solved with loading dose of lacosamide: clinical and neurophysiological correlates

In most cases, the etiology of epilepsy is unknown, although some individuals may develop epilepsy as a result of certain brain injuries, following a stroke, a brain tumor or because of drugs and alcohol. Even some rare genetic mutations may be related to the onset of the condition. Seizures are the result of excessive and abnormal activity of neurons in the cerebral cortex. In this case report we show a clinical case of refractory epilepsy due to pain related to uncontrolled dysmenorrhea. The patient, 43 yrs old, had a history of epilepsy of 20 years and ovarian cancer. She was treated with lamotrigine, clonazepam and levomepromazina maleato. At admission the patient shew seizures due to pain related to dysmenorrhea. In emergency we treated with verapamil hydrochloride 10 mg ev, subsequently verapamil hydrochloride 20 mg in 250 ml of saline solution as maintenance dose. Then we decided to administer a loading dose of 100 mg cpr of Lacosamide to stop the treatment with verapamil hydrochloride. With Lacosamide we solved the seizures in 24 hours.

WITHDRAWN: Anticonvulsants for fibromyalgia

BACKGROUND

Fibromyalgia (FM) is a clinically well-defined chronic condition of unknown aetiology characterised by chronic widespread pain that often co-exists with sleep problems and fatigue. People often report high disability levels and poor health-related quality of life (HRQoL). Drug therapy focuses on reducing key symptoms and disability, and improving HRQoL. Anticonvulsants (antiepileptic drugs) are drugs frequently used for the treatment of chronic pain syndromes.

OBJECTIVES

To assess the benefits and harms of anticonvulsants for treating FM symptoms.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 8, 2013), MEDLINE (1966 to August 2013), PsycINFO (1966 to August 2013), SCOPUS (1980 to August 2013) and the reference lists of reviewed articles for published studies and www.clinicaltrials.gov (to August 2013) for unpublished trials.

SELECTION CRITERIA

We selected randomised controlled trials of any formulation of anticonvulsants used for the treatment of people with FM of any age.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data of all included studies and assessed the risks of bias of the studies. We resolved discrepancies by discussion.

MAIN RESULTS

We included eight studies: five with pregabalin and one study each with gabapentin, lacosamide and levetiracetam. A total of 2480 people were included into anticonvulsants groups and 1099 people in placebo groups. The median therapy phase of the studies was 13 weeks. The amount and quality of evidence were insufficient to draw definite conclusions on the efficacy and safety of gabapentin, lacosamide and levetiracetam in FM. The amount and quality of evidence was sufficient to draw definite conclusions on the efficacy and safety of pregabalin in FM. Therefore, we focused on our interpretation of the evidence for pregabalin due to our greater certainty about its effects and its greater relevance to clinical practice. All pregabalin studies had a low risk of bias. Reporting a 50% or greater reduction in pain was more frequent with pregabalin use than with a placebo (risk ratio (RR) 1.59; 95% confidence interval (CI) 1.33 to 1.90; number needed to treat for an additional beneficial outcome (NNTB) 12; 95% CI 9 to 21). The number of people who reported being 'much' or 'very much' improved was higher with pregabalin than with placebo (RR 1.38; 95% CI 1.23 to 1.55; NNTB 9; 95% CI 7 to 15). Pregabalin did not substantially reduce fatigue (SMD -0.17; 95% CI -0.25 to -0.09; 2.7% absolute improvement on a 1 to 50 scale) compared with placebo. Pregabalin had a small benefit over placebo in reducing sleep problems by 6.2% fewer points on a scale of 0 to 100 (standardised mean difference (SMD) -0.35; 95% CI -0.43 to -0.27). The dropout rate due to adverse events was higher with pregabalin use than with placebo use (RR 1.68; 95% CI 1.36 to 2.07; number needed to treat for an additional harmful outcome (NNTH) 13; 95% CI 9 to 23). There was no significant difference in serious adverse events between pregabalin and placebo use (RR 1.03; 95% CI 0.71 to 1.49). Dizziness was reported as an adverse event more frequently with pregabalin use than with placebo use (RR 3.77; 95% CI 3.06 to 4.63; NNTH 4; 95% CI 3 to 5).

AUTHORS' CONCLUSIONS

The anticonvulsant, pregabalin, demonstrated a small benefit over placebo in reducing pain and sleep problems. Pregabalin use was shown not to substantially reduce fatigue compared with placebo. Study dropout rates due to adverse events were higher with pregabalin use compared with placebo. Dizziness was a particularly frequent adverse event seen with pregabalin use. At the time of writing this review, pregabalin is the only anticonvulsant drug approved for treating FM in the US and in 25 other non-European countries. However, pregabalin has not been approved for treating FM in Europe. The amount and quality of evidence were insufficient to draw definite conclusions on the efficacy and safety of gabapentin, lacosamide and levetiracetam in FM.

Effects of arachidonyl-2'-chloroethylamide (ACEA) on the protective action of various antiepileptic drugs in the 6-Hz corneal stimulation model in mice

Accumulating evidence indicates that cannabinoid CB₁ receptor ligands play a pivotal role in seizures, not only in preclinical studies on animals, but also in clinical settings. This study was aimed at characterizing the influence of arachidonyl-2′-chloroethylamide (ACEA–a selective cannabinoid CB₁ receptor agonist) co-administered with phenylmethylsulfonyl fluoride (PMSF) on the anticonvulsant potency of various antiepileptic drugs (clobazam, lacosamide, levetiracetam, phenobarbital, tiagabine and valproate) in the 6-Hz corneal stimulation model. Psychomotor seizures in male albino Swiss mice were evoked by a current (32 mA, 6 Hz, 3 s stimulus duration) delivered via corneal electrodes. Potential adverse effects produced by the antiepileptic drugs in combination with ACEA+PMSF were assessed using the chimney test (motor performance), passive avoidance task (remembering and acquisition of learning), and grip-strength test (muscular strength). Brain concentrations of antiepileptic drugs were measured by HPLC to exclude any pharmacokinetic contribution to the observed effect. ACEA (5 mg/kg, i.p.) + PMSF (30 mg/kg, i.p.) significantly potentiated the anticonvulsant potency of levetiracetam (P<0.05), but not that of clobazam, lacosamide, phenobarbital, tiagabine or valproate in the 6-Hz corneal stimulation model. Moreover, ACEA+PMSF did not significantly affect total brain concentrations of levetiracetam in mice. No behavioral side effects were observed in animals receiving combinations of the studied antiepileptic drugs with ACEA+PMSF. In conclusion, the combined administration of ACEA+PMSF with levetiracetam is associated with beneficial anticonvulsant pharmacodynamic interaction in the 6-Hz corneal stimulation model. The selective activation of cannabinoid CB₁ receptor-mediated neurotransmission in the brain may enhance levetiracetam-related suppression of seizures in epilepsy patients, contributing to the efficacious treatment of epilepsy in future.

The efficacy of different kinds of intravenously applied antiepileptic drugs in the treatment of status epilepticus. How can it be determined?

We explored the influence of four different efficacy criteria on the results of observational studies concerning the treatment of status epilepticus (SE) and its subtypes. We compared and contrasted the results of four different efficacy criteria for the effectiveness of phenytoin, valproate, levetiracetam, and lacosamide. Criterion 1=the last antiepileptic drug (AED) administered before SE termination. Criterion 2=the last drug introduced into the antiepileptic therapy within 72h before the cessation of SE and without changes in dosage or number of the co-medication. Criterion 3=the last drug introduced into the antiepileptic therapy or increased in dose within 24h before termination of the SE without changes in the co-medication. Criterion 4=the last drug introduced into the antiepileptic therapy within 72h before the cessation of SE even allowing changes in the co-medication. We used two-tailed χ²-tests with the Yates adjustment for small samples to evaluate statistical differences between efficacy rates of different AEDs in the entire group and in subgroups of SE according to the second level of subdivisions in axis 1 and according to axis 2 of the new ILAE classification. A total of 145 treatment episodes in 124 patients (47 male, 77 female) were evaluated. There were 23 significant differences in efficacy according to the different criteria. Only criteria 1 and 3 led to significant results in our analysis. When incorporating theoretical considerations and the results of this study, criterion 3 seems to be the most appropriate measure for the evaluation of efficacy of an AED in the treatment of SE, because it seems to be more reasonable than criterion 1.

Intravenous lacosamide in status epilepticus: Correlation between loading dose, serum levels, and clinical response

INTRODUCTION

Intravenous lacosamide (LCM) is increasingly used in the treatment of status epilepticus (SE), but optimal loading dose and target serum levels are unclear. We analysed the correlation between LCM serum levels after intravenous loading dose and clinical response.

MATERIALS AND METHODS

Retrospective study in two centres from December 2014 to May 2016 including consecutive SE patients treated with LCM, in which trough serum levels after intravenous loading dose were available. Trough levels were correlated with the loading dose and the clinical response, defined as LCM introduction terminating SE without the need of further treatment. Correlations were adjusted for other SE characteristics.

RESULTS

Among 40 patients, 16 (40%) responded to LCM. LCM serum concentrations within the reference interval (10-20mg/l) were associated with loading doses of >9mg/kg (p=0.003; χ2). However, we observed no difference between LCM serum levels in responders (median 10.4mg/l) versus non-responders (median 9.5mg/l; p=0.36; U test), even after adjusting for other predictors of clinical outcome (SE severity, aetiology, and number of previous treatment).

DISCUSSION

High intravenous LCM loading doses (>9mg/kg) were associated with serum levels within the reference interval, there was however no correlation with the clinical response. Prospective studies are needed to evaluate the benefit of increasing the LCM loading dose in SE.

Mechanism of sodium channel block by local anesthetics, antiarrhythmics, and anticonvulsants

Local anesthetics, antiarrhythmics, and anticonvulsants include both charged and electroneutral compounds that block voltage-gated sodium channels. Prior studies have revealed a common drug-binding region within the pore, but details about the binding sites and mechanism of block remain unclear. Here, we use the x-ray structure of a prokaryotic sodium channel, NavMs, to model a eukaryotic channel and dock representative ligands. These include lidocaine, QX-314, cocaine, quinidine, lamotrigine, carbamazepine (CMZ), phenytoin, lacosamide, sipatrigine, and bisphenol A. Preliminary calculations demonstrated that a sodium ion near the selectivity filter attracts electroneutral CMZ but repels cationic lidocaine. Therefore, we further docked electroneutral and cationic drugs with and without a sodium ion, respectively. In our models, all the drugs interact with a phenylalanine in helix IVS6. Electroneutral drugs trap a sodium ion in the proximity of the selectivity filter, and this same site attracts the charged group of cationic ligands. At this position, even small drugs can block the permeation pathway by an electrostatic or steric mechanism. Our study proposes a common pharmacophore for these diverse drugs. It includes a cationic moiety and an aromatic moiety, which are usually linked by four bonds.

Posterior reversible encephalopathy syndrome in alcoholic hepatitis: Hepatic encephalopathy a common theme

Posterior reversible encephalopathy syndrome (PRES) is a neuro-radiologic diagnosis that has become more widely recognized and reported over the past few decades. As such, there are a number of known risk factors that contribute to the development of this syndrome, including volatile blood pressures, renal failure, cytotoxic drugs, autoimmune disorders, pre-eclampsia, and eclampsia. This report documents the first reported case of PRES in a patient with severe alcoholic hepatitis with hepatic encephalopathy and delves into a molecular pathophysiology of the syndrome.

Changes in hormone and lipid levels in male patients with focal seizures when switched from carbamazepine to lacosamide as adjunctive treatment to levetiracetam: A small phase IIIb, prospective, multicenter, open-label trial

Treatment with enzyme-inducing antiepileptic drugs (AEDs) such as carbamazepine (CBZ) can lead to changes in reproductive, endocrine, and lipid parameters, resulting in clinical symptoms for some patients. Previous studies indicate that these changes can be reversed by switching to a nonenzyme-inducing AED. Lacosamide is a newer-generation AED, not known to induce or strongly inhibit cytochrome P450 (CYP450) enzymes. In this phase IIIb, prospective, multicenter, open-label, single-arm trial (NCT01375374), the serum concentrations of CYP-related reproductive hormones, thyroid hormones, and lipids were assessed in otherwise healthy male patients with focal seizures (N=11), before and after a switch from CBZ (600-1200mg/day at baseline) to lacosamide (target dose: 400mg/day by the end of titration) as adjunctive treatment to the nonenzyme-inducing AED levetiracetam (LEV, stable dosage of >1000mg/day throughout). Cross titration took place over 4weeks, followed by an 8-week maintenance period. Serum measurements were conducted at baseline and at the end of maintenance. The median serum sex-hormone-binding globulin (SHBG) concentration was towards the higher end of the normal range at baseline and decreased following the switch (61.7 to 47.5nmol/L, N=10, p=0.027 by Wilcoxon signed-rank test). Free androgen index (100×testosterone/SHBG) and free thyroxine serum concentration increased (25.4 to 36.4 and 13.0 to 14.9pmol/L, respectively, both N=10 and p=0.002). At baseline, the median progesterone serum concentration was below the normal range (0.7nmol/L), whereas median cholesterol and low-density lipoprotein concentrations were above the normal range (5.5 and 3.6mmol/L, respectively). By the end of maintenance, all measured parameters were within the normal range. The safety and tolerability profile of lacosamide was consistent with that observed in previous studies. Furthermore, antiseizure efficacy appeared to be maintained, suggesting that deinduction of CYP enzymes following a switch from CBZ to lacosamide as adjunctive therapy to LEV is feasible within 8weeks and is associated with normalization of serum parameters.

[Lacosamide and neuropathic pain, a review]

INTRODUCTION

Most of the clinical practice guidelines consulted agree that tricyclics, dual (venlafaxine/duloxetine) antidepressants, gabapentin/pregabalin antiepileptic drugs, lidocaine 5% patches and capsaicin 8% patches are the first-line drugs in the treatment of peripheral neuropathic pain, being tramadol and some strong opioids (morphine, oxycodone and tapentadol) second-line drugs treatment. Moreover, the prevalence of neuropathic pain refractory to treatment is about 1.5% of the population, so that an estimated 50% of patients not responding to prescribed treatment. There are other antiepileptic drugs who not have neuropathic pain indication by regulatory agencies, such as lamotrigine, topiramate or oxcarbazepine, but are used in routine clinical practice off-label.

DEVELOPMENT

Following a literature search, we reviewed the use of lacosamide in neuropathic pain, both in various animal models and in different human studies.

CONCLUSIONS

Treatment with lacosamide in neuropathic pain of various etiologies could be considered as an effective alternative for patients who do not respond or not tolerate standard treatments. However, most of the available evidence, except phase II/III clinical trials in diabetic neuropathic pain, corresponds to open and observational studies without a control group, and low number of patients; but the favorable results invite to investigate further the usefulness of lacosamide in neuropathic pain.

[Clinical experience with lacosamide in Galicia: the GALACO study]

INTRODUCTION

Lacosamide is a sodium channel blocker antiepileptic drug authorized as an adjunctive therapy for focal seizures in adolescents and adults.

AIM

To analyze the efficacy and safety of lacosamide in Galicia according to its use in daily clinical practice.

PATIENTS AND METHODS

Retrospective observational study in patients who started treatment with lacosamide between January 2014 and June 2013 in 10 hospitals in Galicia, Spain. Its efficacy and safety at 3, 6 and 12 months after starting lacosamide was assessed.

RESULTS

We included 184 patients with a mean age of 44.2 ± 17.4 years old; 56.5% (n = 104) were male; 173 patients constituted the efficacy population. Mean duration of epilepsy was 18.8 ± 15.5 years. Seizure frequency was 2.5 ± 1.6 episodes/month. After 12 months, 68.2% of patients (n = 118) had >= 50% improvement (responders) and among them, 54 (45.8% of responder patients) were seizure free. Twenty-three percent (n = 43) suffered from adverse events after 12 months, being dizziness (10.3%) and instability (3.3%) the most frequently reported. After the 12 month visit, 87.5% of patients (n = 161) continued treatment with lacosamide.

CONCLUSIONS

Lacosamide provides a very good efficacy and safety profile for patients with focal refractory epilepsy. High percentage of responders may be related to a less refractory population compared to other daily clinical practice studies. It constitutes an attractive therapeutic option for the treatment of focal epilepsies.

Lacosamide modulates interictal spiking and high-frequency oscillations in a model of mesial temporal lobe epilepsy

OBJECTIVE

Nearly one third of patients presenting with mesial temporal lobe epilepsy (MTLE), the most prevalent lesion-related epileptic disorder in adulthood, do not respond to currently available antiepileptic medications. Thus, there is a need to identify and characterize new antiepileptic drugs. In this study, we used the pilocarpine model of MTLE to establish the effects of a third generation drug, lacosamide (LCM), on seizures, interictal spikes and high-frequency oscillations (HFOs, ripples: 80-200 Hz, fast ripples: 250-500 Hz).

METHODS

Sprague-Dawley rats (250-300 g) were injected with pilocarpine to induce a status epilepticus (SE) that was pharmacologically terminated after 1h. Eight pilocarpine-treated rats were then injected with LCM (30 mg/kg, i.p.) 4h after SE and daily for 14 days. Eight pilocarpine-treated rats were used as controls and treated with saline. Three days after SE, all rats were implanted with bipolar electrodes in the hippocampal CA3 region, entorhinal cortex (EC), dentate gyrus (DG) and subiculum and EEG-video monitored from day 4 to day 14 after SE.

RESULTS

LCM-treated animals showed lower rates of seizures (0.21 (± 0.11) seizures/day) than controls (2.6 (±0.57), p<0.05), and a longer latent period (LCM: 11 (± 1) days, controls: 6.25 (± 1), p<0.05). Rates of interictal spikes in LCM-treated rats were significantly lower than in controls in CA3 and subiculum (p<0.05). Rates of ripples and fast ripples associated with interictal spikes in CA3 and subiculum as well as rates of fast ripples occurring outside of interictal spikes in CA3 were also significantly lower in LCM-treated animals. In controls, interictal spikes and associated HFOs correlated to seizure clustering, while this was not the case for isolated HFOs.

SIGNIFICANCE

Our findings show that early treatment with LCM has powerful anti-ictogenic properties in the pilocarpine model of MTLE. These effects are accompanied by decreased rates of interictal spikes and associated HFOs. Isolated HFOs were also modulated by LCM, in a manner that appeared to be unrelated to its antiictogenic effects. These results thus suggest that distinct mechanisms may underlie interictal-associated and isolated HFOs in the pilocarpine model of MTLE.

Lacosamide add-on therapy for partial epilepsy

BACKGROUND

Around half of people with epilepsy will not achieve seizure freedom on their first antiepileptic drug; many will require add-on treatment with another drug. Sometimes multiple treatment combinations are tried to achieve maximum seizure control, although around a third of people do not achieve complete seizure control. Lacosamide is an antiepileptic drug that has been licensed as an add-on treatment for partial epilepsy.

OBJECTIVES

To evaluate the efficacy and tolerability of lacosamide when used as an add-on treatment for patients with drug-resistant partial epilepsy.

SEARCH METHODS

We searched the Cochrane Epilepsy Group's Specialized Register (21 May 2015), the Cochrane Central Register of Controlled Trials (CENTRAL , The Cochrane Library Issue 4, April 2015), MEDLINE (Ovid, 1946 to 21 May 2015), Scopus (1823 to 13 November 2014), ClinicalTrials.gov (21 May 2015) and the WHO International Clinical Trials Registry Platform (ICTRP, 21 May 2015). We imposed no language restrictions. We contacted UCB (sponsors of lacosamide) and experts in the field.

SELECTION CRITERIA

Randomised controlled trials of add-on lacosamide in people with drug-resistant partial epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and extracted the relevant data. We assessed the following outcomes: (1) 50% or greater reduction in seizure frequency; (2) seizure freedom; (3) treatment withdrawal for any reason; and (4) adverse events. Primary analyses were intention-to-treat. Summary risk ratios were estimated for each outcome.

MAIN RESULTS

We included three trials in our review (1311 participants), which were classified as having low risk of bias. All trials were placebo-controlled and assessed doses ranging from 200 mg to 600 mg per day. Trial duration ranged from 24 to 26 weeks. All trials used adequate methods of randomisation and were double-blind. Overall the quality of the evidence was rated as moderate to high. The overall risk ratio for a 50% or greater reduction in seizure frequency for all doses of lacosamide compared with placebo was 1.70 (95% confidence interval (CI) 1.38 to 2.10); for seizure freedom for all doses of lacosamide compared with placebo was 2.50 (95% CI 0.85 to 7.34); and for treatment withdrawal for all doses of lacosamide compared with placebo was 1.88 (95% CI 1.40 to 2.52). Adverse effects significantly associated with lacosamide were abnormal co-ordination (risk ratio (RR) 6.12, 99% CI 1.35 to 27.77), diplopia (RR 5.29, 99% CI 1.97 to 14.23), dizziness (RR 3.53, 99% CI 2.20 to 5.68), nausea (RR 2.37, 99% CI 1.23 to 4.58) and vomiting (RR 3.49, 99% CI 1.43 to 8.54). Adverse effects that were not statistically significant were headache (RR 1.34, 99% CI 0.83 to 2.18), fatigue (RR 2.11, 99% CI 0.92 to 4.85), nystagmus (RR 1.47, 99% CI 0.61 to 3.52) and somnolence (RR 1.44, 99% CI 0.67 to 3.09).

AUTHORS' CONCLUSIONS

This review has shown lacosamide to be effective and fairly well tolerated in the short term when used as add-on treatment for drug-resistant partial epilepsy in adults. Higher doses of lacosamide may be more associated with adverse effects and withdrawal of the drug than lower doses. Additional evidence on children is needed, and longer-term efficacy is unknown.

Demonstration of ameliorative effect of lacosamide: in a rat model of sepsis-induced critical illness polyneuropathy

OBJECTIVES

Critical illness neuropathy (CIN) is a condition that may occur in diseases with severe systemic response, particularly in sepsis. The aim of this study is to investigate the potential anti-inflammatory and lipid-peroxidation inhibiting activities of lacosamide by measuring tumour necrotizing factor-alpha (TNF-alpha), C-reactive protein (CRP), malondialdehyde (MDA) and white blood cells (WBC) using electroneuromyography (ENMG) in rats with sepsis-induced critical illness neuropathy (SICIN).

METHODS

Cecal ligation and puncture (CLP) procedure was performed on 39 rats to induce a sepsis model. The study groups were designed as follows: Group 1: normal (nonoperative); Group 2: (sham-operated); Group 3: CLP (untreated group); Group 4: CLP and lacosamide 20 mg/kg; Group 5: CLP and lacosamide 40 mg/kg. TNF-alpha, C reactive protein, MDA and WBC levels was measured and compound muscle action potential (CMAP) distal latans, amplitudes were measured by using ENMG in rats with SICIN.

RESULTS

When untreated sepsis group was compared with both control and sham groups, CMAP amplitudes and latans were significantly lower (P < 000.1). When CLP, CLP+lacosamide 20 mg/kg and CLP+lacosamide 40 mg/kg groups were compared, plasma levels of TNF-alpha and MDA were significantly higher in the untreated CLP group (F = 12.74, P < 0.0001), (F = 19.43, P < 0.05). In the CLP+lacosamide 40 mg/kg group, CRP levels were significantly lower only compared to the CLP group (P < 0.001).

DISCUSSION

We have showed that lacosamide may have beneficial effects on early SICIN by its potential anti-inflammatory and lipid peroxidation inhibiting activities; however, further comprehensive studies are required to clarify these effects.

Clinical experiences in adult partial epilepsy]

OBJECTIVE

A retrospective study in adult partial epilepsy on the efficacy of lacosamide in relation to previous antiepileptic drug experiences.

METHOD

We analysed 3-65 months' data on epilepsy-care of 43 pharmacoresistant partial epilepsy patients treated with lacosamide. Further analysis of antiepileptic drug history was carried out in strictly selected subgroups of patients with good and poor therapeutic response to lacosamide (10 and 9 patients, respectively) for 2-10 years long retrospective follow up.

PATIENTS

Adult patients with partial-onset seizures had been treated previously with three or more lifetime antiepileptic drugs without permanent success.

RESULTS

Six patients (14%) were seizure free, eleven patients (25%) have experienced important improvement (their seizure-frequency decreased by at least 50%) for more than 12 months. Fourteen patients (32%) improved for less than 6 months and then have relapsed; and add-on lacosamide proved ineffective in 12 patients (28%). Those selected 10 patients successfully treated with lacosamide (seizure free for at least six months) favourably responded to carbamazepine or oxcarbazepine earlier and levetiracetam was ineffective or even caused worsening. The selected lacosamide-unresponsive nine patients responded unfavourably to carbamazepine or oxcarbazepine earlier. Fifteen patients (35%) suffered side effects as dizziness or sleepiness, in 11 of them lacosamide was combined with a "traditional" sodium-channal blocker antiepileptic drug.

CONCLUSION

Lacosamide is an effective add-on antiepileptic drug in difficult-to treat adult partial epilepsy patients. Our data suggest that good lacosamide response may be expected in those patients who reacted favourably to "traditional" sodium-channel blocker carbamazepine or oxcarbazepine earlier.

[Reversible neuropsychological deterioration associated to zonisamide in a paediatric patient with tuberous sclerosis]

AIM

To document reversible cognitive deterioration associated to high doses of zonisamide, using the Reliable Change Index to control practice effects derived from repetitive neuropsychological assessments.

CASE REPORT

A 11 year-old boy with tuberous sclerosis complex and left frontal refractory epilepsy, evaluated within a paediatric epilepsy surgery program. The epileptogenic zone was found to be related with a tuber situated on the left inferior frontal gyrus. The effects of high doses of zonisamide simulate a disturbance of eloquent cortex within the epileptogenic zone and the impact of uncontrolled seizures on cognitive functioning over the language-dominant hemisphere. Drug withdrawal significantly improved total intelligence index, verbal comprehension intellectual index and specific language-sustained cognitive abilities, beyond practice effects.

CONCLUSIONS

The differentiation between cognitive effects of drugs and functional deficits resulting from eloquent cortex involvement within the epileptogenic zone can be of crucial importance in the decision-making process for epilepsy surgery.

The role of slow and persistent TTX-resistant sodium currents in acute tumor necrosis factor-α-mediated increase in nociceptors excitability

Tetrodotoxin-resistant (TTX-r) sodium channels are key players in determining the input-output properties of peripheral nociceptive neurons. Changes in gating kinetics or in expression levels of these channels by proinflammatory mediators are likely to cause the hyperexcitability of nociceptive neurons and pain hypersensitivity observed during inflammation. Proinflammatory mediator, tumor necrosis factor-α (TNF-α), is secreted during inflammation and is associated with the early onset, as well as long-lasting, inflammation-mediated increase in excitability of peripheral nociceptive neurons. Here we studied the underlying mechanisms of the rapid component of TNF-α-mediated nociceptive hyperexcitability and acute pain hypersensitivity. We showed that TNF-α leads to rapid onset, cyclooxygenase-independent pain hypersensitivity in adult rats. Furthermore, TNF-α rapidly and substantially increases nociceptive excitability in vitro, by decreasing action potential threshold, increasing neuronal gain and decreasing accommodation. We extended on previous studies entailing p38 MAPK-dependent increase in TTX-r sodium currents by showing that TNF-α via p38 MAPK leads to increased availability of TTX-r sodium channels by partial relief of voltage dependence of their slow inactivation, thereby contributing to increase in neuronal gain. Moreover, we showed that TNF-α also in a p38 MAPK-dependent manner increases persistent TTX-r current by shifting the voltage dependence of activation to a hyperpolarized direction, thus producing an increase in inward current at functionally critical subthreshold voltages. Our results suggest that rapid modulation of the gating of TTX-r sodium channels plays a major role in the mediated nociceptive hyperexcitability of TNF-α during acute inflammation and may lead to development of effective treatments for inflammatory pain, without modulating the inflammation-induced healing processes.

[Effectiveness of lacosamide in the treatment of refractory neuropathic pain: an open observational trial]

INTRODUCTION

Although different treatments are available for neuropathic pain, these patients are often refractory, which makes it necessary to test treatments that, as they have proven useful in other pathologies, could be effective in neuropathic pain.

PATIENTS AND METHODS

The study made use of the medical records of patients who had been treated with lacosamide for neuropathic pain in different hospitals in the central area of the peninsula and who fulfilled similar characteristics in terms of refractoriness to other standard treatments, in a follow-up that lasted at least six months, or who had had to stop treatment with that drug for some reason or another. A sample of 114 patients (61 males and 53 females) with a mean age of 60.5 years was obtained from the data.

RESULTS

The most common causes of neuropathic pain were: diabetic polyneuropathy (31.6%), post-herpes neuralgia (22.8%), trigeminal neuralgia (17.5%), suboccipital and lumbar-radicular neuralgia (both 12.3%). Effectiveness was good/very good in most patients, with the mean score on the visual analogue scale after six months dropping from 7.7 to 4.8. No serious side effects were reported in any of the patients, but in 12 and 10 patients no recordings were made beyond six months, due to ineffectiveness and intolerance to the treatment, respectively.

CONCLUSIONS

Treatment with lacosamide in neuropathic pain due to different causes could be considered an effective and well-tolerated alternative for patients who fail to respond to standard treatments.

[Effect of lacosamide on the quality of life of patients with epilepsy]

INTRODUCTION

Epilepsy causes psychiatric disorders in 20-40% of patients impacting negatively on their quality of life. Lacosamide is a new antiepileptic as adjunctive therapy in partial seizures with or without generalization.

AIM

We conducted a study to assess the impact of lacosamide as to the quality of life of epileptic patients. We used the HAD scale for anxiety and depression and QOLIE-10 scale for quality of life. We evaluated the efficacy and tolerability.

PATIENTS AND METHODS

We collected prospectively poorly controlled epileptic patients are and added lacosamide treatment. Baseline visit, at 3 and 6 months were performed. The questionnaires are completed and the epilepsy information has been collected.

RESULTS

31 patients, age 45.5 ± 17.2 years, 64.5% males are included. Number of previous monthly crisis 1.6 ± 1.8. HAD anxiety scale shows a significant improvement at 3 and 6 months. HAD scale for depression reflects a significant improvement in quality parameters. QOLIE-10 shows significant improvement for the group with low quality of life after 3 and 6 months. After 6 months 61.3% of patients have a seizure reduction equal or more than 50% and 54.8% are seizure free. Dizziness is the most common side effect (22.8%). 74.2% continued treatment.

CONCLUSIONS

Lacosamide may improve anxiety, depression and quality of life of epileptic patients regardless of seizure control. Response to treatment, adherence and side effects are similar to previous studies.

Conversion to lacosamide monotherapy in the treatment of focal epilepsy: results from a historical-controlled, multicenter, double-blind study

OBJECTIVE

To evaluate the efficacy and safety of conversion to lacosamide 400 mg/day monotherapy in adults with focal epilepsy.

METHODS

This historical-controlled, double-blind study (NCT00520741) enrolled patients aged 16-70 years on stable doses of 1-2 antiepileptic drugs (AEDs) and experiencing 2-40 partial-onset seizures per 28 days during the 8-week prospective Baseline. Patients were randomized to lacosamide 400 or 300 mg/day (3:1 ratio), starting at 200 mg/day and titrated over 3 weeks to randomized dose. Patients then withdrew background AEDs over 6 weeks and entered a 10-week Monotherapy Phase. The primary assessment was the Kaplan-Meier-predicted percentage of patients on 400 mg/day in the full analysis set (FAS) meeting ≥ 1 predefined seizure-related exit criterion by day 112, compared with the historical-control threshold (65.3%).

RESULTS

Four hundred twenty-five patients were enrolled and were eligible for safety analyses (400 mg/day, n = 319; 300 mg/day, n = 106). A total of 271 (63.8%) of 425 patients completed the Lacosamide Maintenance Phase (combined AED Withdrawal and Monotherapy Phases). Among 284 patients in the 400 mg/day group in the FAS, 82 (28.9%) met ≥ 1 exit criterion; the Kaplan-Meier-predicted exit percentage at day 112 for 400 mg/day (30.0%; 95% confidence interval [CI] 24.6-35.5%) was lower than the historical control. When exit events, withdrawal due to treatment-emergent adverse events (TEAEs), and withdrawal due to lack of efficacy were summed (n = 90), the predicted exit percentage (32.3%; 95% CI 26.8-37.8%) was also lower than the historical control. Most patients receiving 400 mg/day reported some improvement on the Clinical Global Impression of Change (75.4%) and Patient Global Impression of Change (74.3%). Overall, the most common (>10%) TEAEs were dizziness (24.0%), headache (14.4%), nausea (13.4%), convulsion (11.5%), somnolence (10.4%), and fatigue (10.1%); most (74.1%) were mild-to-moderate in intensity. Seventy-two patients (16.9%) discontinued due to TEAEs. Seventeen patients (4%, all receiving 400 mg/day) experienced serious AEs.

SIGNIFICANCE

Lacosamide 400 mg/day monotherapy was effective, with a favorable safety profile in patients with focal epilepsy.

Effect of morphine and lacosamide on levels of dopamine and 5-HIAA in brain regions of rats with induced hypoglycemia

The study aimed to determine the effect of morphine and lacosamide on levels of dopamine and 5-HIAA in a hypoglycemic model. Female Wistar rats (n = 30), mean weight of 180 g were treated as follow: Group 1 (control) received 0.9% NaCl, Group II; morphine (10 mg kg(-1)), Group III; lacosamide (10 mg kg(-1)), Group IV; insulin (10 U.I. per rat), Group V; morphine (10 mg kg(-1))+insulin, Group VI; lacosamide (10 mg kg(-1))+ insulin. All administrations were made intraperitoneally every 24 h, for 5 days. Animals were sacrificed after the last dose to measure the levels of glucose in blood; dopamine and 5-HIAA in cortex, hemispheres and cerebellum/medulla oblongata regions. Levels of glucose decreased significantly in animals treated with morphine, lacosamide and all groups that received insulin alone or combined with respect to control group. Levels of Dopamine diminished significantly in cortex and increased significantly in hemispheres of animals that received morphine. In cortex, 5-HIAA increase significantly in the groups treated with morphine, morphine+insulin and lacosamide+insulin, however a significant decrease of the same substance was witnessed in cerebellum and medulla oblongata of animals that received morphine or lacosamide plus insulin. GSH increased significantly in cortex and cerebellum/medulla oblongata of animals treated with morphine and lacosamide alone or combined with insulin. Lipid peroxidation decreased significantly in cortex and cerebellum/medulla oblongata of groups that received lacosamide alone or combined with insulin. These results indicate that hypoglycemia induced changes in cellular regulation while morphine and lacosamide are accompanied by biochemical responses.

Anticonvulsants for fibromyalgia

BACKGROUND

Fibromyalgia (FM) is a clinically well-defined chronic condition of unknown aetiology characterised by chronic widespread pain that often co-exists with sleep problems and fatigue. People often report high disability levels and poor health-related quality of life (HRQoL). Drug therapy focuses on reducing key symptoms and disability, and improving HRQoL. Anticonvulsants (antiepileptic drugs) are drugs frequently used for the treatment of chronic pain syndromes.

OBJECTIVES

To assess the benefits and harms of anticonvulsants for treating FM symptoms.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 8, 2013), MEDLINE (1966 to August 2013), PsycINFO (1966 to August 2013), SCOPUS (1980 to August 2013) and the reference lists of reviewed articles for published studies and www.clinicaltrials.gov (to August 2013) for unpublished trials.

SELECTION CRITERIA

We selected randomised controlled trials of any formulation of anticonvulsants used for the treatment of people with FM of any age.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data of all included studies and assessed the risks of bias of the studies. We resolved discrepancies by discussion.

MAIN RESULTS

We included eight studies: five with pregabalin and one study each with gabapentin, lacosamide and levetiracetam. A total of 2480 people were included into anticonvulsants groups and 1099 people in placebo groups. The median therapy phase of the studies was 13 weeks. The amount and quality of evidence were insufficient to draw definite conclusions on the efficacy and safety of gabapentin, lacosamide and levetiracetam in FM. The amount and quality of evidence was sufficient to draw definite conclusions on the efficacy and safety of pregabalin in FM. Therefore, we focused on our interpretation of the evidence for pregabalin due to our greater certainty about its effects and its greater relevance to clinical practice. All pregabalin studies had a low risk of bias. Reporting a 50% or greater reduction in pain was more frequent with pregabalin use than with a placebo (risk ratio (RR) 1.59; 95% confidence interval (CI) 1.33 to 1.90; number needed to treat for an additional beneficial outcome (NNTB) 12; 95% CI 9 to 21). The number of people who reported being 'much' or 'very much' improved was higher with pregabalin than with placebo (RR 1.38; 95% CI 1.23 to 1.55; NNTB 9; 95% CI 7 to 15). Pregabalin did not substantially reduce fatigue (SMD -0.17; 95% CI -0.25 to -0.09; 2.7% absolute improvement on a 1 to 50 scale) compared with placebo. Pregabalin had a small benefit over placebo in reducing sleep problems by 6.2% fewer points on a scale of 0 to 100 (standardised mean difference (SMD) -0.35; 95% CI -0.43 to -0.27). The dropout rate due to adverse events was higher with pregabalin use than with placebo use (RR 1.68; 95% CI 1.36 to 2.07; number needed to treat for an additional harmful outcome (NNTH) 13; 95% CI 9 to 23). There was no significant difference in serious adverse events between pregabalin and placebo use (RR 1.03; 95% CI 0.71 to 1.49). Dizziness was reported as an adverse event more frequently with pregabalin use than with placebo use (RR 3.77; 95% CI 3.06 to 4.63; NNTH 4; 95% CI 3 to 5).

AUTHORS' CONCLUSIONS

The anticonvulsant, pregabalin, demonstrated a small benefit over placebo in reducing pain and sleep problems. Pregabalin use was shown not to substantially reduce fatigue compared with placebo. Study dropout rates due to adverse events were higher with pregabalin use compared with placebo. Dizziness was a particularly frequent adverse event seen with pregabalin use. At the time of writing this review, pregabalin is the only anticonvulsant drug approved for treating FM in the US and in 25 other non-European countries. However, pregabalin has not been approved for treating FM in Europe. The amount and quality of evidence were insufficient to draw definite conclusions on the efficacy and safety of gabapentin, lacosamide and levetiracetam in FM.

[Lacosamide as an alternative in the treatment of post-surgery neuropathic pain in an allergic patient]

INTRODUCTION

Neuropathic pain is a condition that is still not well understood, although it affects a significantly high percentage of the population. The main problem lies in the fact that it can become a fairly disabling pathology. The most frequent treatment is based essentially on two drugs: gabapentin and pregabalin. Other pharmaceuticals, such as antidepressants, opioids or N-methyl-D-aspartate receptor antagonists can also be employed in combination with the primary drugs. All the same, treatment remains unsatisfactory. Furthermore, it must be borne in mind that there may be patients who are allergic to the two main drugs.

CASE REPORT

We report the case of a 36-year-old female with neuropathic pain secondary to surgery to correct a neurinoma in the brachial plexus, who could not be treated with gabapentin or pregabalin because of a personal history of allergy to these substances. Treatment with another drug (lacosamide), however, was very effective and displayed a very good response.

CONCLUSIONS

Lacosamide is a third-generation antiepileptic drug that has been proven to be effective, safe and with few side effects. It has been considered a good therapeutic option for the treatment of neuropathic pain in patients who are allergic to pregabalin.

Development of lacosamide for the treatment of partial-onset seizures

Lacosamide is an antiepileptic drug (AED) available in multiple formulations that was first approved in 2008 as adjunctive therapy for partial-onset seizures (POS) in adults. Unlike traditional sodium channel blockers affecting fast inactivation, lacosamide selectively enhances sodium channel slow inactivation. This mechanism of action results in stabilization of hyperexcitable neuronal membranes, inhibition of neuronal firing, and reduction in long-term channel availability without affecting physiological function. Lacosamide has a well-characterized and favorable pharmacokinetic profile, including a fast absorption rate, minimal or no interaction with cytochrome P-450 izoenzymes, and a low potential for drug-drug interactions. Lacosamide clinical development included three placebo-controlled, double-blind, randomized trials conducted in more than 1300 patients, each demonstrating safety and efficacy of lacosamide compared to placebo as adjunctive therapy for adults with POS. The clinical use of lacosamide may broaden, pending results of trials evaluating its use as monotherapy for POS in adults, as treatment for epilepsy in pediatric subjects, and as adjunctive treatment for uncontrolled primary generalized tonic-clonic seizures in those with idiopathic generalized epilepsy.

Meta-analysis of randomized, double-blinded studies with eslicarbazepine acetate, lacosamide and oxcarbazepine

PURPOSE

Analysis of overall tolerability and neurological adverse effects (AEs) of eslicarbazepine acetate (ESL), lacosamide (LCM) and oxcarbazepine (OXC) from double-blind, placebo-controlled trials. Indirect comparisons of patients withdrawing because of AEs, and the incidence of some vestibulocerebellar AEs between these three antiepileptic dugs (AEDs).

METHODS

We searched MEDLINE for all randomized, double-blind, placebo-controlled trials investigating therapeutic effects of fixed oral doses of ESL, LCM and OXC in patients with drug resistant epilepsy. Withdrawal rate due to AEs, percentages of patients with serious AEs, and the proportion of patients experiencing any neurological AE, nausea and vomiting were assessed for their association with the experimental drug. Analyses were performed between recommended daily doses of each AED according to the approved summary of product characteristics (SPC). Risk differences were used to evaluate the association of any AE [99% confidence intervals (CIs)] or study withdrawals because of AEs (95% CIs) with the experimental drug. Indirect comparisons between withdrawal rate and AEs dizziness, coordination abnormal/ataxia and diplopia were estimated according to network meta-analysis (Net-MA).

RESULTS

Eight randomized, placebo-controlled, double-blind trials (4 with ESL, 3 with LCM, and 1 with OXC) were included in our analysis. At high doses (OXC 1200mg, ESL 1200mg and LCM 400mg) there was an increased risk of AE-related study withdrawals compared to placebo for all drugs. Several AEs were associated with the experimental drug. Both number and frequency of AEs were dose-related. At high recommended doses, patients treated with OXC withdrew from the experimental treatment significantly more frequently than patients treated with ESL and LCM. Furthermore, the AEs coordination abnormal/ataxia and diplopia were significantly more frequently observed in patients treated with OXC compared to patients treated with LCM and ESL.

CONCLUSIONS

The overall tolerability of AEDs and the incidence of several neurological AEs were clearly dose-dependent. Indirect comparisons between these AEDs, taking into account dose-effect, showed that OXC may be associated with more frequent neurological AEs than LCM and ESL.