Lacosamide and epilepsy

The effect of lacosamide on calcitonin gene-related peptide serum level in episodic migraine patients: a randomized, controlled trial

BACKGROUND

Migraine affects 11-15% of people worldwide, and the calcitonin gene-related peptide (CGRP) is released during the migraine attack, producing pulsating pain of migraine. Also, lacosamide reacts with collapsin-response mediator protein 2, preventing its phosphorylation and leading to the inhibition of CGRP release in the trigeminal system.

OBJECTIVE

The primary outcome was the difference in the serum level of CGRP-LI after three months of treatment with either lacosamide and ibuprofen or ibuprofen alone in episodic migraine patients. The secondary outcomes were assessing safety and efficacy of lacosamide in episodic migraine patients.

METHODS

We conducted an open-label randomized controlled trial on episodic migraine patients aged 10-55 years diagnosed according to (ICHD-3) in Kafr El-Sheikh University Hospital, Egypt. We assessed serum levels of CGRP-LI before and three months after treatment in our two groups, the lacosamide, and the control groups. We also assessed the side effects of treatment in each group, the percentage of patients who achieved ≥ 50% reduction in the migraine monthly days (MMD) frequency and the percentage of patients who achieved pain freedom within 2 h in ≥ 4 of 5 attacks in each group.

RESULTS

200 episodic migraine patients completed the study. There was a statistically significantly higher reduction in the serum CGRP-LI level in the lacosamide group compared with the control group. In addition, lacosamide was well tolerated by patients. Also, the lacosamide group had statistically significant higher percentage of patients who achieved ≥ 50% reduction in the migraine monthly days (MMD) frequency and pain freedom within two hours in ≥ 4 of 5 attacks with P-values 0.002, 0.02 respectively.

CONCLUSION

The daily use of lacosamide 50 mg Bid for three months in episodic migraine patients was associated with a significant reduction in serum CGRP-LI, better clinical outcomes regarding frequency and duration of migraine attacks, and was well tolerated by patients. These results were derived from an open-label pilot study that needed to be thoroughly investigated by a large-scale, randomized, double-blinded, placebo-controlled study.

TRIAL REGISTRATION

 We registered our trial on ClinicalTrials.gov, named after "The Lacosamide's Effect on Calcitonin Gene-related Peptide in Migraine Patients," and with a clinical trial number (NCT05632133)-August 8, 2023.

Effectiveness and Safety of Lacosamide, A Third-generation Anti-seizure Medication, for Poststroke Seizure and Epilepsy: A Literature Review

Advances in stroke treatment have resulted in a dramatic reduction in stroke mortality. Nevertheless, poststroke seizures and epilepsy are issues of clinical importance affecting survivors. Additionally, stroke is the most common cause of epilepsy in older adults. Although numerous antiseizure medications exist, studies are needed to provide robust evidence of the efficacy and tolerability of these medicines for treating poststroke seizures and epilepsy. Crucially, the newer generations of antiseizure medications require testing. Lacosamide, a third-generation antiseizure medication approved for treating localization-related epilepsy, has a novel mechanism of selectively enhancing the slow inactivation of sodium channels. This literature review evaluated whether lacosamide is effective and safe for the treatment of poststroke seizures and epilepsy. This review critically analyzed studies published in major academic databases (Pubmed, Embase, and Cochrane Library) from inception through June 2022 regarding the interaction of lacosamide with poststroke seizures and epilepsy. We included clinical prospective, retrospective, and case studies on patients with poststroke seizure and epilepsy, lacosamide as a treatment for seizures, neuroprotection in animal models of seizures, and the safety of lacosamide when coadministering anticoagulants. Clinical studies revealed lacosamide to be an effective antiseizure medication with high efficacy and tolerability in patients with poststroke seizures and epilepsy. In animal models, lacosamide proved effective at seizure reduction and neuroprotection. Pharmacokinetic studies demonstrated the safety of lacosamide when coadministering conventional and new anticoagulants. The literature suggests that Lacosamide is a promising candidate antiseizure medication for patients with poststroke seizures and epilepsy.

Evidence for Inhibitory Perturbations on the Amplitude, Gating, and Hysteresis of A-Type Potassium Current, Produced by Lacosamide, a Functionalized Amino Acid with Anticonvulsant Properties

Lacosamide (Vimpat^®, LCS) is widely known as a functionalized amino acid with promising anti-convulsant properties; however, adverse events during its use have gradually appeared. Despite its inhibitory effect on voltage-gated Na⁺ current (I_Na), the modifications on varying types of ionic currents caused by this drug remain largely unexplored. In pituitary tumor (GH₃) cells, we found that the presence of LCS concentration-dependently decreased the amplitude of A-type K⁺ current (I_K(A)) elicited in response to membrane depolarization. The I_K(A) amplitude in these cells was sensitive to attenuation by the application of 4-aminopyridine, 4-aminopyridine-3-methanol, or capsaicin but not by that of tetraethylammonium chloride. The effective IC₅₀ value required for its reduction in peak or sustained I_K(A) was calculated to be 102 or 42 µM, respectively, while the value of the dissociation constant (K_D) estimated from the slow component in I_K(A) inactivation at varying LCS concentrations was 52 µM. By use of two-step voltage protocol, the presence of this drug resulted in a rightward shift in the steady-state inactivation curve of I_K(A) as well as in a slowing in the recovery time course of the current block; however, no change in the gating charge of the inactivation curve was detected in its presence. Moreover, the LCS addition led to an attenuation in the degree of voltage-dependent hysteresis for I_K(A) elicitation by long-duration triangular ramp voltage commands. Likewise, the I_K(A) identified in mouse mHippoE-14 neurons was also sensitive to block by LCS, coincident with an elevation in the current inactivation rate. Collectively, apart from its canonical action on I_Na inhibition, LCS was effective at altering the amplitude, gating, and hysteresis of I_K(A) in excitable cells. The modulatory actions on I_K(A), caused by LCS, could interfere with the functional activities of electrically excitable cells (e.g., pituitary tumor cells or hippocampal neurons).

Drug treatment of epilepsy: From serendipitous discovery to evolutionary mechanisms

Epilepsy is a chronic brain disorder caused by abnormal firing of neurons. Up to now, using antiepileptic drugs is the main method of epilepsy treatment. The development of antiepileptic drugs lasted for centuries. In general, most agents entering clinical practice act on the balance mechanisms of brain "excitability-inhibition". More specifically, they target voltage-gated ion channels, GABAergic transmission and glutamatergic transmission. In recent years, some novel drugs representing new mechanisms of action have been discovered. Although there are about 30 available drugs in the market, it is still in urgent need of discovering more effective and safer drugs. The development of new antiepileptic drugs is into a new era: from serendipitous discovery to evolutionary mechanism-based design. This article presents an overview of drug treatment of epilepsy, including a series of traditional and novel drugs.

New Methods Used in Pharmacokinetics and Therapeutic Monitoring of the First and Newer Generations of Antiepileptic Drugs (AEDs)

The review presents data from the last few years on bioanalytical methods used in therapeutic drug monitoring (TDM) of the 1st-3rd generation and the newest antiepileptic drug (AEDs) cenobamate in patients with various forms of seizures. Chemical classification, structure, mechanism of action, pharmacokinetic data and therapeutic ranges for total and free fractions and interactions were collected. The primary data on bioanalytical methods for AEDs determination included biological matrices, sample preparation, dried blood spot (DBS) analysis, column resolution, detection method, validation parameters, and clinical utility. In conclusion, the most frequently described method used in AED analysis is the LC-based technique (HPLC, UHPLC, USLC) combined with highly sensitive mass detection or fluorescence detection. However, less sensitive UV is also used. Capillary electrophoresis and gas chromatography have been rarely applied. Besides the precipitation of proteins or LLE, an automatic SPE is often a sample preparation method. Derivatization was also indicated to improve sensitivity and automate the analysis. The usefulness of the methods for TDM was also highlighted.

Cortical excitability in epilepsy and the impact of antiepileptic drugs: transcranial magnetic stimulation applications

INTRODUCTION

Epileptic conditions are characterized by impaired cortical excitation/inhibition balance and interneuronal disinhibition. Transcranial magnetic stimulation (TMS) is a neurophysiological method that assesses brain excitation/inhibition.

AREA COVERED

This review was written after a detailed search in PubMed, EMBASE, ISI web of science, SciELO, Scopus, and Cochrane Controlled Trials databases from 1990 to 2020. It summarizes TMS applications for diagnostic and therapeutic purposes in epilepsy. TMS studies help to distinguish different epilepsy conditions and explore the antiepileptic drugs' (AEDs') effects on neuronal microcircuits and plasticity mechanisms. Repetitive TMS studies showed that low-frequency rTMS (0.33-1 Hz) can reduce seizures' frequency in refractory epilepsy or pause ongoing seizures; however, there is no current approval for its use in such patients as adjunctive treatment to AEDs.

EXPERT OPINION

There are variable and conflicting TMS results which reflect the distinct pathogenic mechanisms of each epilepsy condition, the dynamic epileptogenic process over the long disease course resulting in the development of recurrent spontaneous seizures and/or progression of epilepsy after it is established, and the differential effect of AEDs on cortical excitability. Future epilepsy research should focus on combined TMS/functional connectivity studies that explore the complex cortical excitability circuits and networks using different TMS parameters and techniques.

Cognitive and Behavioral Comorbidities: An Unwanted Effect of Antiepileptic Drugs in Children

Epilepsy is one of the most common neurological disorders and, despite optimally chosen and dosed antiepileptic drugs (AEDs), approximately 20%-30% of patients will continue to have seizures. Behavior and cognition are negatively impacted by seizures, but AEDs are also a major contributor to behavioral and cognitive deficits. However, the cognitive and behavioral effect of AEDs in children is insufficiently emphasized in the literature. This review summarizes the cognitive and behavioral effects of AEDs in the pediatric population with the objective of helping pediatricians and pediatric neurologists to select the AEDs with the best profile for their individual patient's needs.

Lacosamide as add-on treatment of focal symptomatic epilepsy in a patient with alcoholic liver cirrhosis

The occurrence of epileptic seizures in the presence of hepatic disease is not uncommon in clinical practice. Selecting an appropriate AED for patients affected by liver failure who have new-onset epileptic seizures can be challenging. We describe a 64-year-old man affected by liver cirrhosis. The patient developed partial epilepsy with secondary generalization because of an intracerebral hemorrhage in the left parieto-occipital regions. After the neurosurgery procedure, seizures reappeared and were initially managed with levetiracetam. After one month, the patient experienced clusters of seizures while on stable treatment with levetiracetam. Pregabalin as add-on was not tolerated; therefore, he received a low dose of phenobarbital as add-on treatment. The patient developed hepatic encephalopathy. Phenobarbital was immediately stopped, and oral lacosamide was added. A rapid recovery of encephalopathy with a 6-month seizure freedom was obtained. The patient died 6 months later because of progressive impairment of liver function. Lacosamide may represent an alternative to other AEDs in patients with liver failure; however, further prospective evaluation of its efficacy and safety in this clinical setting is needed.

Single-dose oral lacosamide in refractory simple partial status epilepticus: case report and review

OBJECTIVES

This study aimed to present 2 patients with simple partial refractory status epilepticus (RSE) treated with a single oral lacosamide (LCM) dose and to review the literature on this topic.

METHOD

A retrospective description of 2 patients with simple partial RSE treated with 300 mg of LCM per os (p.o.) and a literature review were done.

RESULTS

Both patients responded to single-dose oral LCM treatment with seizure cessation after 30 minutes.

CONCLUSIONS

This is the first report on successful treatment of simple partial RSE with a single-dose of LCM p.o.. Oral LCM might represent an option for treatment of patients presenting with simple partial RSE.

Comparative study of lacosamide and classical sodium channel blocking antiepileptic drugs on sodium channel slow inactivation

Many antiepileptic drugs (AEDs) exert their therapeutic activity by modifying the inactivation properties of voltage-gated sodium (Na(v) ) channels. Lacosamide is unique among AEDs in that it selectively enhances the slow inactivation component. Although numerous studies have investigated the effects of AEDs on Na(v) channel inactivation, a direct comparison of results cannot be made because of varying experimental conditions. In this study, the effects of different AEDs on Na(v) channel steady-state slow inactivation were investigated under identical experimental conditions using whole-cell patch-clamp in N1E-115 mouse neuroblastoma cells. All drugs were tested at 100 μM, and results were compared with those from time-matched control groups. Lacosamide significantly shifted the voltage dependence of Na(v) current (I(Na) ) slow inactivation toward more hyperpolarized potentials (by -33 ± 7 mV), whereas the maximal fraction of slow inactivated channels and the curve slope did not differ significantly. Neither SPM6953 (lacosamide inactive enantiomer), nor carbamazepine, nor zonisamide affected the voltage dependence of I(Na) slow inactivation, the maximal fraction of slow inactivated channels, or the curve slope. Phenytoin significantly increased the maximal fraction of slow inactivated channels (by 28% ± 9%) in a voltage-independent manner but did not affect the curve slope. Lamotrigine slightly increased the fraction of inactivated currents (by 15% ± 4%) and widened the range of the slow inactivation voltage dependence. Lamotrigine and rufinamide induced weak, but significant, shifts of I(Na) slow inactivation toward more depolarized potentials. The effects of lacosamide on Na(v) channel slow inactivation corroborate previous observations that lacosamide has a unique mode of action among AEDs that act on Na(v) channels.