Lacosamide in patients with pharmacoresistant epilepsy

First add-on lacosamide treatment in children with focal epilepsy in China: A multi-centre real-life cohort study

AIM

To assess the effectiveness and safety of lacosamide (LCM) as the first add-on therapy for children with focal epilepsy at multiple centres in China.

METHOD

Children aged 4-16 years with focal epilepsy from 13 epilepsy centres were included in this study. All patients were treated with LCM as the first add-on treatment and followed up for 26 weeks. The seizure frequency, seizure-free rate, ≥50% response rate, retention rate, and incidence of adverse drug reactions after the addition of LCM were analysed.

RESULTS

Ninety-nine children (58 males; aged 4-16 years; mean age 8.51 ± 2.95 years) were enroled. The mean age at first seizure was 5.74 ± 3.12 years. All patients were administered LCM as the first add-on treatment for focal epilepsy. Twenty-eight patients (28/99, 28.28%) did not experience seizures during the follow-up period. The ≥50% response rates were 80.81% (80/99), 93.88% (92/98), 98.98% (97/98), and 100.0% (98/98) at 6 weeks (visit two), 10 weeks (visit three), 18 weeks (visit four), and 26 weeks (visit five), respectively, compared to that at baseline (visit one). The intelligence scores decreased in 12 participants, remained unchanged in 64, and increased in 16. Adverse events occurred in three participants during the trial, all of which were mild.

INTERPRETATION

LCM was effective as the first add-on therapy in this real-life multi-centre study of a paediatric population with focal epilepsy. Further prospective studies with long-term follow-up periods are needed to confirm the effectiveness and tolerability of LCM.

Pharmacodynamic interactions of antiepileptic drugs: From bench to clinical practice

BACKGROUND

Approximately 50% of patients do not achieve seizure control with antiepileptic drug (AED) monotherapy, and polytherapy, with more than one AED, is often required. To date, no evidence-based criteria on how to combine AEDs exist.

OBJECTIVE

This narrative review aimed to provide critical findings of the available literature about the role of pharmacodynamic AEDs' interactions in patients whose epilepsies were treated with polytherapy.

METHODS

Electronic databases, Medical Literature Analysis and Retrieval System Online (MEDLINE) and Excerpta Medica dataBASE (EMBASE), were systematically searched to identify relevant studies on pharmacodynamic AEDs' interactions in patients with epilepsy.

RESULTS AND CONCLUSION

Most data on AED combinations are coming from animal models and preclinical studies. Combining AEDs with different mechanisms of actions seems to have greater effectiveness and lower risk of adverse event development. Conversely, the combination of AEDs may cause pharmacodynamic synergistic effects that may result in not only increased efficacy but also more adverse effects. Despite some AED associations that have been proven to be effective in specific epilepsy/seizure type (e.g., phenobarbital+/phenytoin for tonic seizures and ethosiximide + valproate for absences; lamotrigine + valproate for various epilepsy/seizure types), no clear and definitive evidence exists about AED combinations in humans. Examples of pharmacodynamic interactions that possibly explain the synergistic effects on efficacy or adverse effects include the combination between vigabatrin or pregabalin and sodium channel blockers (supra-additive antiseizure effect) and lacosamide combined with other sodium channel blockers (infra-additive antiseizure effect and neurotoxicity synergistic). The pharmacodynamic lamotrigine-valproate interaction is also supported by synergistic adverse events. Therefore, well-designed double-blind prospective studies recruiting a sufficient number of patients possibly with a crossover design and carefully ascertain the role of pharmacokinetic interactions and variations of AEDs' levels in the blood are needed.

A novel action of lacosamide on GABAA currents sets the ground for a synergic interaction with levetiracetam in treatment of epilepsy

Epilepsy is one of the most common chronic neurological diseases, and its pharmacological treatment holds great importance for both physicians and national authorities, especially considering the high proportion of drug-resistant patients (about 30%). Lacosamide (LCM) is an effective and well-tolerated new-generation antiepileptic drug (AED), currently licensed as add-on therapy for partial-onset seizures. However, LCM mechanism of action is still a matter of debate, although its effect on the voltage sensitive sodium channels is by far the most recognized. This study aimed to retrospectively analyze a cohort of 157 drug-resistant patients treated with LCM to describe the most common and effective therapeutic combinations and to investigate if the LCM can affect also GABA_A-mediated neurotransmission as previously shown for levetiracetam (LEV). In our cohort, LEV resulted the compound most frequently associated with LCM in the responder subgroup. We therefore translated this clinical observation into the laboratory bench by taking advantage of the technique of "membrane micro-transplantation" in Xenopus oocytes and electrophysiological approaches to study human GABA_A-evoked currents. In cortical brain tissues from refractory epileptic patients, we found that LCM reduces the use-dependent GABA impairment (i.e., "rundown") that it is considered one of the specific hallmarks of drug-resistant epilepsies. Notably, in line with our clinical observations, we found that the co-treatment with subthreshold concentrations of LCM and LEV, which had no effect on GABA_A currents on their own, reduced GABA impairment in drug-resistant epileptic patients, and this effect was blocked by PKC inhibitors. Our findings demonstrate, for the first time, that LCM targets GABA_A receptors and that it can act synergistically with LEV, improving the GABAergic function. This novel mechanism might contribute to explain the clinical efficacy of LCM-LEV combination in several refractory epileptic patients.

The effectiveness and safety of lacosamide in children with epilepsy in a clinical practice setting

BACKGROUND

Seizures in up to 30% of children with epilepsy become refractory to treatment, decreasing their quality of life. Studies suggest that lacosamide may be effective in pediatric patients with refractory epilepsy.

AIMS

To assess the effectiveness and safety of lacosamide in a population of children with mostly focal refractory epilepsy.

METHODS

Retrospective analysis of children aged <18years presenting to a single hospital in Spain. Data from baseline, and 3, 6, and 12months after lacosamide initiation were collected and analyzed. Response to lacosamide was categorized by seizure frequency (seizure freedom or ≥75%, ≥50%, and <50% reduction in seizures).

RESULTS

One hundred ninety-one pediatric patients (~55% male) with focal epilepsy treated with lacosamide were included. The mean age at lacosamide initiation was 9.4years, and the mean duration of epilepsy was 5.4years. Seizure-free rates at 3, 6, and 12months were 9.7%, 11.8%, and 16.0%. At 12months, 44.4% of the population had a ≥50% reduction in seizure frequency. When analyzing response according to the number of previous/concomitant AEDs, those patients who received ≤2 previous AEDs/fewer concomitant AEDs had significantly greater response rates than those who received greater numbers of previous/concomitant AEDs; however, no predictive factors for response were identified. The most common adverse events were seizure number increased (14.7%), diplopia (5.2%), dizziness (3.7%), ataxia (2.1%), and drowsiness (2.1%).

CONCLUSIONS

Lacosamide use in children with refractory focal epilepsy can result in a reduction in seizure rate that improves progressively over time with few adverse effects, making lacosamide a promising option in these patients.

Lacosamide as adjunctive therapy in treatment-resistant epilepsy in childhood

AIMS

Lacosamide (LCM) is a novel anti-epileptic drug (AED) that enhances the slow inactivation of voltage-gated sodium channels. Its efficacy as adjunctive therapy for focal seizures is confirmed in adult placebo controlled trials with >50% reduction in seizure frequency in up to 50% patients. There is paucity of data on its efficacy and tolerance in treatment-resistant epilepsy in childhood (TREC). This study aims to assess efficacy and tolerance of LCM as adjunct therapy in TREC.

METHODS

Audit of medical records and seizure diaries in children with TREC on LCM. A response (RR) was defined as ≥50% reduction in seizure frequency.

RESULTS

Forty children (age range: 2-19 years) with TREC received LCM as add-on therapy. All had abnormal electroencephalograms, and 36 had abnormal neuroimaging. All children failed >2 AED trials, nine had trialled the ketogenic diet, five had failed the vagal nerve stimulator and 11 had failed resective epilepsy surgery. Median dose and duration of LCM therapy were 5.7 mg/kg/day and 10.5 months, respectively. RR was seen in 20% with persistence of RR in 8/36, 8/30 and 8/26 children on LCM at 3-, 6- and 9-month follow-up. Two children became seizure free. Retention on LCM was 65% at 9 months. LCM was well tolerated with minor side effects in seven children; no child discontinued LCM because of side effects.

CONCLUSION

LCM is a well-tolerated AED with RR in 20%: in 5%, it resulted in seizure freedom. LCM may be useful even in TREC when seizures have not responded to intervention with multiple modalities.

Safety of lacosamide in children with refractory partial epilepsy

OBJECTIVES

The study was carried out to investigate the safety of lacosamide on children with refractory partial epilepsy.

MATERIALS & METHODS

The study was carried out at a tertiary care hospital after obtaining approval from the institutional ethics committee. Patients aged between 5 and 15 years taking oral lacosamide (LCM) tablets that were given orally as an adjunctive anti-epileptic drug were enrolled for assessing safety, tolerability and its effect on the behavioural life at every visit of titration, during the treatment period (3 months) and at 2 follow up visits that were done at monthly intervals. Adverse events reported by caregiver or by investigator were recorded. Patients/caregivers also completed a 25 items on Connor's behavioural rating clinical scale at every visit.

RESULTS

Out of 531 screened patients, 79 patients with refractory partial epilepsy were enrolled after they fulfilled the inclusion and exclusion criteria. Mean age of the children was 8.84 ± 3.09 years (5-15 years), of which 53 were males and 26 females. The mean age at onset of seizures in males was 6.46 ± 3.57 and in females, 6.38 ± 3.39 years. Seventy-six children of 79, completed 3 months of treatment period showed significant (p < 0.001) decrease in the frequency of seizures, significant improvement in behaviour and showed good tolerability. Three (3.79%) patients dropped out of the study due to hyperactive behaviour, vomiting and lack of seizure control respectively.

CONCLUSIONS

Lacosamide is a well-tolerated newer antiepileptic drug that is effective in refractory partial epilepsy paediatric patients and concurrently improved patient's behaviour.

Update on the use of lacosamide in the treatment of partial-onset seizures

ABSTRAT: 

Lacosamide has a novel mechanism of action, namely selective enhancement of slow inactivation of voltage-gated sodium channels. Trial data and clinical experience indicate that it is effective in the treatment of partial-onset seizures, and that it is well tolerated. Pivotal early clinical trials demonstrated median percent reductions in seizure frequency ranging from 26 to 35.3% in the 200 mg/day, from 36.4 to 39% in the 400 mg/day, and from 37.8 to 40% in the 600 mg/day treatment groups. Dose-related adverse events were similar in the early clinical trials, and were mainly CNS complaints including dizziness, nausea, vomiting, fatigue, ataxia, abnormal vision, diplopia and nystagmus. Because of the dose-dependent adverse events and lack of additional efficacy at the 600 mg/day daily dose, lacosamide has been approved as an adjunctive treatment at recommended daily doses of 200–400 mg/day.