Lacosamide: new adjunctive treatment option for partial-onset seizures

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.

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.

Treatment and care of women with epilepsy before, during, and after pregnancy: a practical guide

Women with epilepsy (WWE) wishing for a child represent a highly relevant subgroup of epilepsy patients. The treating epileptologist needs to delineate the epilepsy syndrome and choose the appropriate anti-seizure medication (ASM) considering the main goal of seizure freedom, teratogenic risks, changes in drug metabolism during pregnancy and postpartum, demanding for up-titration during and down-titration after pregnancy. Folic acid or vitamin K supplements and breastfeeding are also discussed in this review. Lamotrigine and levetiracetam have the lowest teratogenic potential. Data on teratogenic risks are also favorable for oxcarbazepine, whereas topiramate tends to have an unfavorable profile. Valproate needs special emphasis. It is most effective in generalized seizures but should be avoided whenever possible due to its teratogenic effects and the negative impact on neuropsychological development of in utero-exposed children. Valproate still has its justification in patients not achieving seizure freedom with other ASMs or if a woman decides to or cannot become pregnant for any reason. When valproate is the most appropriate treatment option, the patient and caregiver must be fully informed of the risks associated with its use during pregnancies. Folate supplementation is recommended to reduce the risk of major congenital malformations. However, there is insufficient information to address the optimal dose and it is unclear whether higher doses offer greater protection. There is currently no general recommendation for a peripartum vitamin K prophylaxis. During pregnancy most ASMs (e.g. lamotrigine, oxcarbazepine, and levetiracetam) need to be increased to compensate for the decline in serum levels; exceptions are valproate and carbamazepine. Postpartum, baseline levels are reached relatively fast, and down-titration is performed empirically. Many ASMs in monotherapy are (moderately) safe for breastfeeding and women should be encouraged to do so. This review provides a practically oriented overview of the complex management of WWE before, during, and after pregnancy.

Healthcare resource utilization and costs before and after lacosamide initiation as adjunctive therapy among patients with epilepsy in the United States

OBJECTIVE

The objective of this study was to evaluate all-cause and epilepsy-specific healthcare resource utilization and costs following lacosamide (LCM) initiation as adjunctive therapy for the treatment of epilepsy.

METHODS

A noninterventional retrospective database analysis was conducted that examined patients diagnosed as having epilepsy who added LCM to existing antiepileptic drug (AED) therapy between 2009 and 2016 (the first LCM prescription was the index event). This study used a single-case design whereby patients served as their own controls. Patients were further required to have a minimum of 12 months of continuous eligibility before (preindex period) and after (postindex period) their index event. In the 12-month postindex period, the only allowed AED regimen change was the addition of LCM. Demographic and clinical characteristics were measured at index and during the preindex period, respectively. All-cause and epilepsy-specific healthcare resource utilization and costs were measured and compared in the pre- and postindex periods. Paired t- and McNemar's tests were conducted to assess the significant differences between pre- and postindex. Univariate analyses were used to analyze the impact of LCM on specific subpopulations.

RESULTS

The study sample comprised of 2171 patients: mean (standard deviation [SD]) age: 38.9 (19.3) years; 52.6% female. Just over half (56%) of these patients were on monotherapy before adding LCM. Prior to adding LCM, 28.8% of patients had an epilepsy-specific inpatient (IP) admission, and 35.7% of patients had an all-cause IP admission, compared with 18.2% and 26.1% of patients in the post-LCM period, respectively (both p < 0.0001). Likewise, 35.6% of patients had an epilepsy-specific emergency room (ER) visit, and 50.0% had an all-cause ER visit prior to adding LCM, compared with 23.8% and 42.1% in post-LCM, respectively (both p < 0.0001). After adding LCM, one-year mean [SD] epilepsy-specific IP admission costs decreased by 42.9% ($13,647 [$52,290] to $7788 [$32,321]), and all-cause IP admission costs decreased by 38.6% ($20,654 [$72,716] to $12,688 [$46,120]) (both p < 0.0001). One-year epilepsy-specific mean [SD] ER costs decreased by 35.2% ($691 [$1756] to $448 [$1909]; p < 0.0001), and all-cause ER cost decreased by 17.8% ($1217 [$3014] to $1000 [$2970]; p < 0.01).

CONCLUSIONS

Epilepsy-related IP hospitalizations and ER visits (indicators of seizures) were significantly reduced in patients with epilepsy 12 months after adding LCM as an adjunctive therapy to existing AED treatment in a real-world setting, leading to reduced healthcare resource utilization and epilepsy costs.

Overall systematic approach to sepsis damages on urogenital tissues: protective power of lacosamide

PURPOSE

The aim of the study was to evaluate the harmful effects of sepsis on the urogynecological tissues and the ability of Lacosamide (LCM) on Lipopolysaccharide (LPS)-induced cytokine production, oxidative stress and apoptotic pathways, in the experimental rat sepsis model.

METHODS

Twenty-four female Wistar albino rats (12 months old) were divided into 3 groups as follows: control group (Group I) (0.1 ml/oral and i.p. saline, single dose), sepsis group (Group II) (5 mg/kg LPS, i.p. single dose) and sepsis + LCM group (Group III) (5 mg/kg LPS, i.p. single dose and 40 mg/kg LCM). Six hours after the last LPS administration, the animals were sacrificed. Subsequently, the analyses of urogenital tissues total oxidant/antioxidant status, histopathological and immunohistochemical analyses were performed.

RESULTS

Total oxidant capacity (TOC) and oxidative stress index (OSI) values in the urogenital tissues were increased in the urogenital tissues in Group II [Total antioxidant capacity (TAC) was decreased] compared to group I (p < 0.05). LCM improved these values (p < 0.05). The immunohistochemical markers (Tumor Necrosis Factor-alpha (TNF-α), interleukin-1 beta (IL-1β), heat shock protein 70 (HSP-70), C-reactive protein (CRP), Malondialdehyde (MDA) were significantly increased in Group II (p < 0.001). With the administration of LCM (Group III), the expressions of above-mentioned markers were markedly decreased (p < 0.001). Marked hyperemia and slight hemorrhages with neutrophil leukocyte infiltrations were seen histopathologically in Group II. LCM treatment ameliorated the pathological findings.

CONCLUSION

These findings demonstrated that sepsis caused oxidative stress, apoptosis and inflammation in the urogenital tissues. We revealed that LCM ameliorated the damage caused by sepsis in urogenital tissue.

Lacosamide Pharmacokinetics in a Critically Ill Patient During Continuous Renal Replacement Therapy

The objective of this study is to describe the pharmacokinetics of lacosamide in a critically ill adult during continuous venovenous hemofiltration (CVVH). A 78-year-old male developed sepsis and acute kidney injury following cardiac surgery. He was initially treated with intermittent hemodialysis but developed nonconvulsive status epilepticus at the end of the first session and was subsequently initiated on CVVH. In addition to lorazepam boluses, levetiracetam, and midazolam infusion, he was loaded with lacosamide 400 mg intravenously and started on 200 mg intravenously twice daily as maintenance therapy. Noncompartmental modeling of lacosamide pharmacokinetics revealed significant extracorporeal removal, a volume of distribution of 0.69 L/kg, elimination half-life of 13.6 hours, and peak and trough concentrations of 7.4 and 3.7 mg/L, respectively (goal trough, 5-10 mg/L). We found significant extracorporeal removal of serum lacosamide during CVVH, which was higher than previously reported. This led to subtherapeutic concentrations and decreased overall antiepileptic drug exposure. The relationship between serum lacosamide concentrations and clinical efficacy is not well understood; thus, therapeutic drug monitoring is not routinely recommended. Yet, we demonstrated that measuring serum lacosamide concentrations in the critically ill population during continuous renal replacement therapy may be useful to individualize dosing programs. Further pharmacokinetic studies of lacosamide may be necessary to generate widespread dosing recommendations.

Newer Antiepileptic Drugs for Status Epilepticus in Adults: What's the Evidence?

Status epilepticus (SE) is one of the most frequent neurological emergencies. Despite this, understanding of its pathophysiology and evidence regarding its management is limited. Rapid, effective, and well-tolerated treatment to achieve seizure cessation is advocated to prevent brain damage or potentially lethal outcomes. The last two decades have witnessed an exponential increase in the number of available antiepileptic drugs (AEDs). These compounds, especially lacosamide and levetiracetam, in view of their intravenous formulation, have been increasingly prescribed in SE. These and other newer AEDs present a promising profile in terms of tolerability, with few centrally depressive effects, favorable pharmacokinetic properties, and fewer drug interactions than classical AEDs; conversely, they are more expensive. There is still no clear evidence to suggest a specific beneficial impact of newer AEDs on SE outcome, preventing any strong recommendation regarding their prescription in SE. Further comparative studies are urgently required to clarify their place and optimal use in the armamentarium of SE treatment.

An Updated Overview on Therapeutic Drug Monitoring of Recent Antiepileptic Drugs

Given the distinctive characteristics of both epilepsy and antiepileptic drugs (AEDs), therapeutic drug monitoring (TDM) can make a significant contribution to the field of epilepsy. The measurement and interpretation of serum drug concentrations can be of benefit in the treatment of uncontrollable seizures and in cases of clinical toxicity; it can aid in the individualization of therapy and in adjusting for variable or nonlinear pharmacokinetics; and can be useful in special populations such as pregnancy. This review examines the potential for TDM of newer AEDs such as eslicarbazepine acetate, felbamate, gabapentin, lacosamide, lamotrigine, levetiracetam, perampanel, pregabalin, rufinamide, retigabine, stiripentol, tiagabine, topiramate, vigabatrin, and zonisamide. We describe the relationships between serum drug concentration, clinical effect, and adverse drug reactions for each AED as well as the different analytical methods used for serum drug quantification. We discuss retrospective studies and prospective data on the serum drug concentration-efficacy of these drugs and present the pharmacokinetic parameters, oral bioavailability, reference concentration range, and active metabolites of newer AEDs. Limited data are available for recent AEDs, and we discuss the connection between drug concentrations in terms of clinical efficacy and nonresponse. Although we do not propose routine TDM, serum drug measurement can play a beneficial role in patient management and treatment individualization. Standardized studies designed to assess, in particular, concentration-efficacy-toxicity relationships for recent AEDs are urgently required.

Pharmacodynamics and common drug-drug interactions of the third-generation antiepileptic drugs

INTRODUCTION

Anticonvulsants that belong to the third generation are considered as 'newer' antiepileptic drugs, including: eslicarbazepine acetate, lacosamide, perampanel, brivaracetam, rufinamide and stiripentol. Areas covered: This article reviews pharmacodynamics (i.e. mechanisms of action) and clinically relevant drug-drug interactions of the third-generation antiepileptic drugs. Expert opinion: Newer antiepileptic drugs have mechanisms of action which are not shared with the first and the second generation anticonvulsants, like inhibition of neurotransmitters release, blocking receptors for excitatory amino acids and new ways of sodium channel inactivation. New mechanisms of action increase chances of controlling forms of epilepsy resistant to older anticonvulsants. Important advantage of the third-generation anticonvulsants could be their little propensity for interactions with both antiepileptic and other drugs observed until now, making prescribing much easier and safer. However, this may change with new studies specifically designed to discover drug-drug interactions. Although the third-generation antiepileptic drugs enlarged therapeutic palette against epilepsy, 20-30% of patients with epilepsy is still treatment-resistant and need new pharmacological approach. There is great need to explore all molecular targets that may directly or indirectly be involved in generation of seizures, so a number of candidate compounds for even newer anticonvulsants could be generated.

Dose effects of lacosamide as add-on therapy for partial-onset seizure in adult

The objective of the study was to evaluate the dose effects of lacosamide on the efficacy and safety as adjunctive therapy for partial-onset seizure in adults. We searched online databases such as Pubmed, Embase, Cochrane Online Library, and Clinicaltrial.gov for randomized control trials. A meta-analysis was performed on RevMan 5.3 software. Four randomized control trials with 1855 patients out of 310 citations and 30 registered trials were identified. 400 mg/d was more effective than 200 mg/d [RR 1.23 (95 % CI 1.05-1.45), P = 0.01], but the 600 mg/d didn't show more benefit than 400 mg/d [RR 1.01 (95 % CI 0.81-1.27), P = 0.90]. Increasing the dosage led to higher incidence of quitting the medication because of adverse events [400 vs. 200 mg/d RR 2.17 (95 % CI 1.15-4.11), P = 0.02; 600 vs. 400 mg/d RR 1.55 (95 % CI 1.12-2.15), P = 0.009]. Incidence of serious adverse events did not occur with the increase of dose [400 vs. 200 mg/d RR 1.26 (95 % CI 0.50-3.20), P = 0.62], [600 vs. 400 mg/d RR 0.52 (95 % CI 0.21-1.30), P = 0.16]. A dose of 400 mg/d resulted in a higher chance of dizziness [RR 1.50 (95 % CI 1.02-2.20), P = 0.04], vomiting [RR 1.73 (95 % CI 1.03-2.90), P = 0.04], and diplopia [RR 1.98 (95 % CI 1.19-3.30), P = 0.008] than that of 200 mg/d. 400 mg/d is the optimal dose for efficacy. The dose of 200 mg/d has the best safety for less occurrence of adverse events and less quitting. Current evidence suggests that a dose of 600 mg/d is unnecessary, except for particular reasons.

Lacosamide serum concentrations in adult patients with epilepsy: the influence of gender, age, dose, and concomitant antiepileptic drugs

OBJECTIVE

Lacosamide (LCM), a new antiepileptic drug (AED) approved as adjunctive therapy for the treatment of patients with partial-onset seizures, has limited pharmacokinetic and drug interaction data. The main objectives of the present study were to investigate the effects of dose, age, gender, and hepatic enzyme-inducing AEDs on the pharmacokinetics of LCM as assessed by steady state serum LCM values.

METHODS

An LCM AED therapeutic drug monitoring database was analyzed with regard to LCM serum concentrations and other relevant patient and AED drug information. One hundred twenty eight sera were identified. These were collected from 68 women and 61 men aged 19-66 years, who were prescribed a median LCM dose of 300 mg (range 50-600 mg).

RESULTS

Serum LCM concentrations were observed in the following main groupings: LCM monotherapy (n = 5), LCM with nonenzyme-inducing AEDs (n = 50), LCM with enzyme-inducing AEDs (n = 49), LCM with valproic acid (n = 20), and LCM with enzyme-inducing AEDs plus valproic acid (n = 4). Analysis of variance showed a correlation of dose with LCM concentrations (r = 0.53, P < 0.001), and women had statistically higher mean LCM concentration than did men, 37.2 ± 23.6 versus 26.8 ± 12.9 μmol/L (P = 0.001). Serum LCM concentrations were significantly lower (P = 0.002) in the enzyme-inducing AED group (carbamazepine and phenytoin) compared with the LCM monotherapy group and the nonenzyme-inducing group, 23.5 ± 11.0, 34.5 ± 7.7, and 32.7 ± 17.9 μmol/L, respectively.

CONCLUSIONS

Serum LCM concentrations increased dose dependently, were age independent, and were higher in women compared with men. Carbamazepine and phenytoin can significantly decrease serum LCM concentrations, probably via induction of LCM metabolism.

Lacosamide as adjunctive therapy in refractory epilepsy in adults: a systematic review

PURPOSE

To review the evidence for efficacy and safety of lacosamide in adult patients with refractory epilepsy and refractory status epilepticus (RSE).

METHODS

A systematic literature search of MEDLINE, PubMed, EMBASE, IPA, Google and Google Scholar (through October 2014) was performed.

RESULTS

Fourteen studies assessing lacosamide in 3509 refractory epilepsy patients were included. In 3 RCTs, more patients had at least 50% reduction in seizure frequency with lacosamide compared to placebo with 38.3-41.1%, 38.1-41.2%, and 18.3-25.8%, in the 400 mg/day, 600 mg/day, and placebo groups, respectively. In non-comparative trials, 18-69% of patients achieved at least 50% reduction in seizure frequency, and 1.7-26.2% achieved seizure freedom. Non-responders were documented in two trials, with 26.2-34% having no response. Thirteen studies assessing lacosamide in 390 RSE patients were included. When assessing lacosamide's ability to terminate RSE, one comparative cohort study found no improvement in SE duration or seizure control with addition of lacosamide. Another study documented no difference compared to use of phenytoin. Eleven descriptive studies using lacosamide as add-on RSE therapy revealed seizure termination rates of 0-100% (median 64.7%). In all patients receiving lacosamide, dizziness (21.8%), vision disturbances (10.4%), drowsiness (7.4%), headache (7.0%), nausea (6.5%), and coordination problems (5.8%) were the most common adverse effects.

CONCLUSION

Based on evidence to date, adjunctive lacosamide is a treatment option to reduce seizure frequency in patients with refractory epilepsy and terminate seizures in patients with RSE. The safety information summary can be used to advise patients of potential adverse effects.

Efficacy and tolerability of lacosamide in the concomitant treatment of 130 patients under 16 years of age with refractory epilepsy: a prospective, open-label, observational, multicenter study in Spain

Background

The safety and effectiveness of lacosamide, an antiepileptic drug (AED) that selectively enhances the slow inactivation of voltage-gated sodium channels without affecting rapid inactivation, has been demonstrated in randomized, double-blind, placebo-controlled trials in adults with focal epileptic seizures. Although lacosamide is approved for use in patients over 16 years of age, limited clinical experience exists for younger patients.

Objective

To assess the efficacy and tolerability of lacosamide in children with refractory epilepsy.

Design/Methods

The trial was a prospective, open-label, observational, multicenter study. A total of 130 patients aged less than 16 years (range 6 months to 16 years) with refractory epilepsy who had initiated treatment with lacosamide were enrolled at 18 neuropediatric units in hospitals across Spain. Patients with a variety of etiologies were enrolled, including those with partial epilepsies and symptomatic, generalized epilepsy syndromes. Lacosamide (VIMPAT®; UCB Pharma SA, Brussels, Belgium) was primarily administered once every 12 hours as an oral solution or as an oral tablet, with an initial dose of 1–2 mg/kg/day in the majority of cases. The majority of patients were also receiving stable concomitant therapy with ≥1 other AED. Treatment response to lacosamide was determined by assessing the change in seizure frequency after 3 months of lacosamide therapy. Responders were defined as patients who achieved a seizure frequency reduction of >50%. Tolerability was assessed by the reporting of adverse effects, laboratory testing, and electroencephalography recordings.

Results

Lacosamide was dosed at a mean of 6.80 ± 2.39 mg/kg/day. After 3 months of lacosamide therapy, 62.3% of patients achieved a >50% reduction in seizure frequency, with complete seizure suppression being reported in 13.8% of patients. Adverse effects occurred in 39 patients (30%), but no dose-response relationship was observed in terms of these events. In ten patients, instability, difficulty walking, an inability to relate to subjective elements, and blurred vision or dizziness were reported. A total of 13 patients discontinued treatment — in five of these patients, symptom intensity remained unchanged despite dose reduction, which led to treatment discontinuation. The symptoms were markedly different in each patient, preventing determination of a causal factor(s).

Conclusions

The results of this study provide preliminary evidence for the efficacy of lacosamide in children with refractory epilepsy. Further evaluation in a randomized, controlled trial is needed to validate the efficacy in this population and to fully investigate the adverse effects described here. We recommend an initial dose of 1–2 mg/kg/day, uptitrated to 6–9 mg/kg/day over 4–6 weeks.

The efficacy and tolerability of perampanel and other recently approved anti-epileptic drugs for the treatment of refractory partial onset seizure: a systematic review and Bayesian network meta-analysis

OBJECTIVES

This paper compares the efficacy and tolerability of perampanel (PER) relative to other recently approved anti-epileptic drug (AEDs) - lacosamide (LCS), retigabine (RTG), and eslicarbazepine (ESL) for the adjunctive treatment of partial onset seizures with or without secondary generalization and specifically in the secondary generalization subgroup.

MATERIALS AND METHODS

A systematic literature review of all RCTs of PER and selected AEDs in EMBASE, Medline, and the Cochrane Central from 1998 to January 2011 with an update in PubMed in March 2013 was performed. A network meta-analysis was conducted for 50% responder rate for overall seizures; withdrawal due to adverse events; seizure freedom; and 50% responder rate for secondary generalized seizures.

RESULTS

Twelve RCTs (three PER, three LCS, three RTG and three ESL) were included. PER performed significantly better than placebo for 'responder rate' (OR 2.151, 95% CrI 1.348-3.472) and 'seizure freedom' (OR 2.507, 95% CrI 1.067-7.429). When compared to other agents, PER was found to be equally effective. For 'withdrawal due to adverse events', PER had the lowest odds ratio vs. placebo compared with other AEDs. In the analysis for the subgroup of patients with secondary generalization, only four RCTs (three PER and one LCS) met the inclusion criteria for one outcome (responder rate) for LCS. In this subgroup, PER was statistically significantly better than placebo (OR 2.448, 95% CrI 1.088-5.828).

CONCLUSION

PER was statistically significantly superior to placebo in responder rate, seizure freedom, and responder rate in the secondary generalization population. Though PER had statistically significant greater withdrawal compared to placebo, it had the lowest ORs vs. placebo, suggesting a superior safety profile among the comparators included in this analysis. In patients with partial onset seizure with secondary generalization, PER had a statistically significant effect on responder rate compared to placebo.

Retrospective analysis of the tolerability and activity of lacosamide in patients with brain tumors

Object

The object of this study was to determine the tolerability and activity of lacosamide in patients with brain tumors.

Methods

The authors reviewed the medical records at 5 US academic medical centers with tertiary brain tumor programs, seeking all patients in whom a primary brain tumor had been diagnosed and who were taking lacosamide.

Results

The authors identified 70 patients with primary brain tumors and reviewed seizure frequency and toxicities. The majority of the patients had gliomas (96%). Fifty-five (78%) had partial seizures only, and 12 (17%) had generalized seizures. Most of the patients (74%) were started on lacosamide because of recurrent seizures. Forty-six patients (66%) reported a decrease in seizure frequency, and 21 patients (30%) reported stable seizures. Most of the patients (54 [77%]) placed on lacosamide did not report any toxicities.

Conclusions

This retrospective analysis demonstrated that lacosamide was both well tolerated and active as an add-on antiepileptic drug (AED) in patients with brain tumors. Lacosamide's novel mechanism of action will allow for concurrent use with other AEDs, as documented by its activity across many different types of AEDs used in this patient population. Larger prospective studies are warranted.

[Therapeutic drug monitoring of lacosamide]

Lacosamide is a third generation antiepileptic drug, available in France since 2008. It is indicated in combination therapy for the treatment of inadequately controlled focal seizures, from the age of 16. The bioavailability of lacosamide is 100% and is unaffected by food intake; protein binding is low; it is metabolized by CYP2C19 into inactive O-desmethyl lacosamide. It does not inhibit or induce cytochromes; the elimination is renal with a half-life of approximately 13 h. The relationship between dose and plasma concentration is established, but there does not appear to be any clear relationship between concentration and efficacy. However, the main side effects are concentration dependent. The potential for drug-drug interaction of lacosamide is low and variability between individuals is minimal. Accordingly, the level of evidence for the therapeutic drug monitoring has been estimated at "probably of no use".

Minimizing pharmacodynamic interactions of high doses of lacosamide

OBJECTIVES

To determine whether pharmacodynamic interactions between high doses of lacosamide (400-800 mg/day) and concomitant sodium channel antiepilepsy drugs (AEDs) can be minimized in patients with drug-resistant partial-onset seizures.

MATERIALS AND METHODS

Patients were rapidly initiated with high-dose lacosamide (100 mg/week; increases to 400 to 800 mg/day), while simultaneously tapering concomitant sodium channel AEDs. Seizure frequency and side effects were evaluated at six time points: baseline, titration, 3, 6, 9 and 12 months.

RESULTS

Twenty-three patients had a baseline median of 4 seizures/month with persisting partial-onset seizures, despite previous treatment with an average of 6.8 AEDs. Mean decreases in monthly seizure frequency were as follows: 3 months 49.9% (P = 0.011), 6 months 55.4% (P = 0.010), 9 months 60.8% (P = 0.002) and 12 months 58.2% (P = 0.011). Most adverse events were mild CNS-related symptoms and occurred transiently only during titration - there was no significant relationship (χ(2) < 1.5, P > 0.1) between lacosamide dose and the presence of side effects at 3, 6, 9 or 12 months.

CONCLUSIONS

Drug-resistant patients rapidly titrated to high doses of lacosamide with simultaneous tapering of traditional sodium channel AEDs had marked reduction in CNS-related adverse events compared with patients treated in three previous pivotal trials that used fixed doses of concomitant AEDs.

Intravenous Lacosamide in refractory nonconvulsive status epilepticus

BACKGROUND

Many patients present with refractory Status epilepticus (SE) despite multiple anti-epileptic drugs (AEDs). Lacosamide (LCM) was recently approved as an adjunct AED for partial-onset seizures. It has unique mechanism of modulating voltage-gated sodium channels by enhancing their slow inactivation. LCM has demonstrated efficacy in animal models of pharmacoresistant seizures. To date, there are isolated anecdotal reports of LCM use in SE.

OBJECTIVE

To report a single center experience with IV Lacosamide in patients with NCSE.

METHODS

Pharmacy records were reviewed to identify patients with SE who received IV LCM in our institution. Data on demographics, response to therapy and adverse effects/outcomes were analyzed. All patients had continuous EEG monitoring.

RESULTS

10 patients (4 men, 6 women), age 16-90 years with refractory SE were given LCM. Eight patients were in focal non-convulsive SE (NCSE), 2 were in generalized non-convulsive SE. The etiologies included anoxic brain injury, idiopathic, encephalitis, tumor, posterior reversible encephalopathy syndrome (PRES), stroke, and AVM. IV LCM was added after traditional AEDs, including drug-induced coma in some, failed to control the SE. NCSE resolved in 7/10 patients whereas 1/10 patient showed partial response with cessation of NCSE but still frequent electrographic seizures and 2/10 patients were resistant to therapy.

CONCLUSIONS

LCM is a useful adjunct in refractory NCSE. The IV formulation allows prompt administration in the intensive care unit setting. Response was seen especially in focal SE. Similar to other AEDs, response was poor in patients with postanoxic injury. Our data is limited by the small number of patients. Larger controlled studies are necessary to assess accurately the efficacy of IV LCM as an early treatment of SE.

Experience with lacosamide in a series of children with drug-resistant focal epilepsy

We report our pediatric experience with lacosamide, a new antiepileptic drug, approved by the US Food and Drug Administration as adjunctive therapy in focal epilepsy in patients more than 17 years old. We retrospectively reviewed charts for lacosamide use and seizure frequency outcome in patients with focal epilepsy (Wilcoxon signed rank test). Sixteen patients (7 boys) were identified (median dose 275 mg daily, 4.7 mg/kg daily; mean age 14.9 years, range 8-21 years). Patients were receiving a median of 2 antiepileptic drugs (interquartile range [IQR] 1.7-3) in addition to having undergone previous epilepsy surgery (n=3), vagus nerve stimulation (n=9), and ketogenic diet (n=3). Causes included structural (encephalomalacia and diffuse encephalitis, 1 each; stroke in 2) and genetic abnormalities (Aarskog and Rett syndromes, 1 each) or cause not known (n=10). Median seizure frequency at baseline was 57 per month (IQR 7-75), and after a median follow-up of 4 months (range 1-13 months) of receiving lacosamide, it was 12.5 per month (IQR 3-75), (P<0.01). Six patients (37.5%; 3 seizure free) were classified as having disease that responded to therapy (≥50% reduction seizure frequency) and 10 as having disease that did not respond to therapy (<50% in 3; increase in 1; unchanged in 6). Adverse events (tics, behavioral disturbance, seizure worsening, and depression with suicidal ideation in 1 patient each) prompted lacosamide discontinuation in 4/16 (25%). This retrospective study of 16 children with drug-resistant focal epilepsy demonstrated good response to adjunctive lacosamide therapy (median seizure reduction of 39.6%; 37.5% with ≥50% seizure reduction) without severe adverse events.

Examining the clinical utility of lacosamide: pooled analyses of three phase II/III clinical trials

BACKGROUND

Lacosamide is an antiepileptic drug (AED) approved for the adjunctive treatment of partial-onset seizures in adults. Completed phase II/III clinical trials of lacosamide provide a valuable opportunity to evaluate clinically relevant aspects of the resulting large patient pool.

OBJECTIVE

To provide insight into the clinical utility of lacosamide by performing a priori-defined and post hoc analyses on a large, pooled patient population.

STUDY DESIGN

Pooled data from three randomized, double-blind, multicentre, placebo-controlled phase II/III trials.

PATIENTS

Adult patients with partial-onset seizures with or without secondary generalization (N = 1294).

INTERVENTION

Four- to six-week titration followed by 12-week maintenance treatment with lacosamide (Vimpat®) 200, 400 or 600 mg/day or placebo.

MAIN OUTCOME MEASURE

A priori-defined primary efficacy variables for the pooled analysis were change in seizure frequency per 28 days and the proportion of patients experiencing a ≥50% reduction in seizure frequency (50% responder rate) from Baseline to the Maintenance Phase; a priori-defined secondary efficacy variables were the proportion of patients achieving a ≥75% reduction in seizure frequency from Baseline to the Maintenance Phase (75% responder rate), the proportion of Maintenance Phase completers remaining seizure free throughout the entire Maintenance Phase and the percentage of seizure-free days during the Maintenance Phase for patients entering the Maintenance Phase. The pooled analyses of the change in seizure frequency, and 50% and 75% responder rates were performed with an intent-to-treat (ITT) approach, including all patients receiving at least one dose of trial medication and having at least one post-baseline efficacy assessment. Similar analyses of the two primary efficacy variables and 75% responder rates were also performed using a modified ITT population (ITTm) that included ITT patients who entered the Maintenance Phase. Additional post hoc efficacy analyses were an evaluation of onset of efficacy and assessment of efficacy in patients grouped by prior surgical history and individual concomitant AED use. In addition, pharmacokinetic-pharmacodynamic modelling was performed, and safety data were assessed.

RESULTS

In this pooled analysis of 1294 difficult-to-treat patients, all three dosages of lacosamide (200, 400 and 600 mg/day) showed a significant improvement compared with placebo for median percent seizure reduction (ITT and ITTm; p < 0.05 for 200 mg/day, p < 0.001 for 400 and 600 mg/day), as well as for 50% responder rate (ITT and ITTm; p < 0.05 for 200 mg/day, p < 0.001 for 400 and 600 mg/day). Evaluation of 75% responder rate in the phase II/III pooled population showed that a significantly higher proportion of patients randomized to lacosamide 400 or 600 mg/day achieved a ≥75% reduction in seizure frequency compared with placebo (ITT and ITTm; p < 0.001); statistical significance was not observed for lacosamide 200 mg/day (ITT and ITTm). A total of 2.7%, 3.3% and 4.8% of patients completing the Maintenance Phase in the lacosamide 200, 400 and 600 mg/day groups, respectively, experienced no seizures throughout the entire Maintenance Phase (placebo group = 0.9%). The mean change from baseline in the percentage of seizure-free days in patients entering the Maintenance Phase for the phase II/III pool was 8.0%, 11.6% and 14.7% with lacosamide 200 (p = 0.077), 400 (p < 0.001) and 600 (p < 0.001) mg/day groups, respectively, compared with 6.1% in the placebo group. The onset of efficacy relative to placebo was evident by the first week of treatment with lacosamide. Efficacy was similar in lacosamide-treated patients reporting prior surgical intervention for epilepsy compared to lacosamide-treated patients with no prior surgical intervention. Lacosamide showed a reduction in seizures, regardless of the concomitant AEDs used. The preferred pharmacokinetic-pharmacodynamic model (E(max)) supported the therapeutic dose range of lacosamide, and no additional safety concerns were identified in the phase II/III pooled analysis.

CONCLUSIONS

Results of these a priori-defined and post hoc pooled data analyses from phase II/III trials demonstrate that lacosamide effectively reduces seizures in patients at all three dosages evaluated with an early onset of efficacy, regardless of patient surgical history and concomitant AED regimen.