Efficacy and safety of lamotrigine in pediatric patients

Safety of lamotrigine in paediatrics: a systematic review

OBJECTIVES

To identify adverse drug reactions associated with lamotrigine in children and compare the safety profile with other antiepileptic drugs.

SETTING

Databases EMBASE (1974-April 2015), MEDLINE (1946-April 2015), PubMed and the Cochrane library for randomised controlled trials were searched for studies on safety of lamotrigine.

PARTICIPANTS

All studies involving paediatric patients aged ≤ 18 years who have received at least a single dose of lamotrigine with safety as an outcome measure were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was safety of lamotrigine. Drug interaction of lamotrigine was the secondary outcome.

RESULTS

A total of 78 articles involving 3783 paediatric patients were identified. There were 2222 adverse events (AEs) reported. Rash was the most commonly reported AE, occurring in 7.3% of the patients. Stevens-Johnson syndrome was rarely reported, with a risk of 0.09 per 100 patients. Discontinuation due to an adverse drug reaction (ADR) was recorded in 72 children (1.9% of all treated patients). Fifty-eight per cent of treatment discontinuation was attributed to different forms of rash and 21% due to increased seizures. Children on lamotrigine monotherapy had lower incidences of AEs. Headache (p=0.02), somnolence (<0.001), nausea (p=0.01), vomiting (p<0.001), dizziness (p<0.001) and abdominal pain (p=0.01) were significantly lower among children on monotherapy.

CONCLUSIONS

Rash was the most common ADR of lamotrigine and the most common reason for treatment discontinuation. Children receiving polytherapy have a higher risk of AEs than monotherapy users.

TRIAL REGISTRATION NUMBER

CRD42013006910.

Clinical management of seizures in newborns : diagnosis and treatment

Neonatal seizures can be classified as tonic, clonic, myoclonic, and subtle. A clinical diagnosis is not easy as seizures are usually subtle in neonates. In the majority of newborn infants seizures are subclinical. On the other hand, not all abnormal movements identified by clinicians as clinical seizures are accompanied by electroencephalographic seizure discharges in the EEG. Precise incidence is difficult to delineate and depends on study population and criteria used for diagnosis of seizures. Controversy exists as to whether neonatal seizures themselves cause damage to the developing brain, or if the damage is primarily due to the underlying cause of the seizures. As a result of this controversy there is ongoing discussion whether all seizures (both clinical and subclinical) should be treated. In addition, when (sub)clinical seizures are treated, there is no consensus about the most appropriate treatment for neonatal seizures and how to assess the efficacy of treatment. Current therapeutic options to treat neonatal seizures (i.e. primarily first-generation antiepileptic drugs [AEDs]) are relatively ineffective. In practice, phenobarbital still remains the drug of first choice for EEG confirmed or suspected seizures. Benzodiazepines are also used in (phenobarbital) refractory cases. Several (small) studies indicate that lidocaine is an effective drug for refractory seizures as second- or third-line treatment. Although data are scarce, some AEDs with a wide acceptance in adult and pediatric neurology practice are being used to treat neonatal seizures (i.e. second-generation AEDs). These drugs are chemically different from all first-generation AEDs and they have an effect on other pathways so they provide new pharmacological targets for controlling seizures in newborns. Levetiracetam, topiramate, felbamate, bumetanide, lamotrigine and vigabatrin are examples of these second-generation AEDs. There is an urgent need for prospective, randomized, controlled trials to assess the efficacy and safety of these second-generation AEDs in neonates. The aim of this review is to provide an overview of the current knowledge of diagnosis, the effect on brain injury, and the treatment of neonatal seizures.

Long-term efficacy of valproate versus lamotrigine in treatment of idiopathic generalized epilepsies in children and adolescents

PURPOSE

In order to estimate and compare the long-term effectiveness of lamotrigine (LTG) versus valproate (VPA) monotherapy in treatment of newly diagnosed idiopathic generalized epilepsies (IGE) the following study was performed.

METHODS

Medical records of 214 children and adolescents suffering from IGE were analyzed. 132 of them were on VPA monotherapy, 82 on LTG. The majority of patients had juvenile myoclonic epilepsy - 98, the rest: juvenile absence epilepsy - 32, childhood absence epilepsy - 53 and epilepsy with a tonic-clonic seizures on awakening - 12, others - 19. Mean age of the patients was 8.9 years (range 4-16 years). The mean time of treatment was 28 months, time of observation 40 months. In order to estimate retention rates and factors predicting successful treatment with LTG and VPA we used Kapplan-Meyer analysis and Gehan tests.

RESULTS

Data analysis showed significantly longer retention rates with VPA versus LTG treatment in overall rates as well in all syndromes subgroups. After 12 months of therapy 69% stayed on LTG therapy versus 89% on VPA, after 24 months 57% versus 83% respectively. VPA showed comparable efficacy in all IGE syndromes where LTG showed better efficacy in childhood and juvenile absence epilepsy than in juvenile myoclonic epilepsy. The shorter duration of treatment with LTG was due to lack of efficacy.

CONCLUSIONS

Our results show the superiority of VPA versus LTG treatment in idiopathic generalized epilepsy syndromes.

Long-term tolerability and efficacy of lamotrigine in infants 1 to 24 months old

This open-label study was designed to evaluate the long-term tolerability and efficacy of lamotrigine in 1- to 24-month-old infants with partial seizures. The study enrolled both lamotrigine-naïve patients and patients who had been previously exposed to lamotrigine in a randomized, double-blind, placebo-controlled study. Patients (n = 204) received lamotrigine according to a dosing schedule that depended on prior experience with lamotrigine and concurrent antiepileptic drug therapy for up to 48 weeks or their second birthday, whichever occurred last. Total duration of lamotrigine exposure (which included exposure during the placebo-controlled study in lamotrigine-experienced patients) was >/=24 weeks in 92% of patients, >/=48 weeks in 70% of patients, and >/=72 weeks in 20% of patients. A total of 20 (10%) patients (8 lamotrigine-naïve patients and 12 lamotrigine-experienced patients) transitioned to lamotrigine monotherapy. The most common adverse events were pyrexia (45% of patients), upper-respiratory tract infection (28%), and ear infection (22%). The only adverse event considered reasonably attributable to study medication in >2% of patients was irritability (n = 10; 5% of patients). No cases of serious rash were reported. The median percent reduction from baseline in partial seizure frequency in the sample as a whole was 74%. Seizure frequency was reduced by >/=50% from pre-lamotrigine baseline in 62% of patients in the sample as a whole, 60% of the lamotrigine-naïve subgroup, and 63% of the lamotrigine-experienced subgroup. In the sample as a whole, 13% of patients were seizure free during the Treatment Phase. Investigators considered clinical status at the last clinic visit to be improved (mildly, moderately, or markedly) relative to prelamotrigine clinical status in 76% of patients (150/197) and to be unchanged in 19% (37/197). In this study-the first large prospective investigation of the long-term tolerability and efficacy of an antiepileptic drug in a patient population 2 years and younger-lamotrigine administered for up to approximately 72 weeks was well tolerated and associated with good seizure control.

Pharmacotherapeutic strategies for pediatric bipolar disorder

There has been a recent increase in recognition and diagnosis of pediatric bipolar disorder (PBD), along with an increase in prescriptions for psychotropic medications for treating children suffering from this chronic, potentially disabling disorder. Lithium remains the only FDA-approved mood stabilizer for use in children > 12 years of age and along with valproic acid and carbamazepine, forms the triad of traditional mood stabilizers used for initiation of treatment for PBD. There has been a recent surge in the use of atypical antipsychotics in PBD, which may be due to their relative ease of administration and lack of requirement for serum level monitoring. A combination of traditional mood stabilizers along with atypical antipsychotics is commonly used in clinical practice, despite a lack of compelling empirical data. Although there is an urgent need for controlled studies on the available treatment options and strategies in PBD, recent expert consensus guidelines and emerging controlled pharmacotherapy data on PBD will lay the platform for future scientific research in the area.

Adjunctive lamotrigine for refractory epilepsy in adolescents with mental retardation

Epilepsy is a major comorbid condition in adolescents with mental retardation and is often characterized by multiple seizure types that are refractory to treatment. This study (n = 22) describes a subanalysis of data from a larger multicenter study of adjunctive lamotrigine therapy in patients with mental retardation and refractory epilepsy and focuses on the outcome measures of seizure reduction, safety and tolerability, and impact on behaviors in adolescents with mental retardation and refractory epilepsy. The study kept baseline antiepileptic drugs constant and titrated lamotrigine over 8 weeks to the target dose, followed by an 8-week maintenance phase and then a 12-week optimization phase during which all antiepileptic drugs and lamotrigine could be altered as clinically indicated. Sixty percent of subjects had a 50% decrease in seizures by the end of the maintenance phase and a mean 39% reduction in seizure frequency by the end of the maintenance phase (25% by end of study) compared with baseline. Global improvements were observed in most patients, with statistically significant improvements in the Aberrant Behavior Checklist and the Habilitative Improvement Scale, which is predictive of less need for supportive care in activities of daily living and thus enhanced potential for greater independence. Lamotrigine-associated improvements in behavior can be attributed to improved control of seizures, a reduction in concomitant antiepileptic drugs, and/or direct mood-stabilizing and behavior-enhancing properties independent of the antiseizure effects of the drug. The results of this study suggest that lamotrigine is an important treatment option in adolescents with mental retardation and comorbid epilepsy.

An open-label study of lamotrigine adjunct or monotherapy for the treatment of adolescents with bipolar depression

OBJECTIVE

The treatment of pediatric bipolar depression has not been well studied. The authors wished to prospectively study the efficacy of lamotrigine as adjunctive or monotherapy in adolescents with bipolar disorder who were experiencing a depressive episode.

METHOD

This was an 8-week open-label trial of lamotrigine with 20 adolescents ages 12-17 years (mean age 15.8; 7 boys, 13 girls) with diagnoses of bipolar disorder I, II, or not otherwise specified, who were experiencing a depressive episode. Lamotrigine was begun at 12.5 to 25 mg/day. Primary response criteria was a 1 or a 2 on the Clinical Global Impression-Improvement at week 8. A secondary criterion was at least a 50% decrease in Children's Depression Rating Scale-Revised scores.

RESULTS

Nineteen subjects completed the trial. The mean final dose was 131.6 mg/day. Seven subjects were taking other psychotropic medications. Sixteen subjects (84%) responded by primary criteria, and 12 (63%) responded to our secondary criteria. Eleven subjects (58%) were considered in remission at week 8. Young Mania Rating Scale and Overt Aggression Scale-Modified scores also decreased significantly during the trial. There was no significant weight change, rash, or other adverse effects during the trial.

CONCLUSIONS

Adolescents with bipolar depression appeared to respond to lamotrigine treatment, whether as adjunctive therapy or monotherapy, with decreases in depression, mania, and aggression. Larger, placebo-controlled studies of lamotrigine are needed in this population.

Pediatric bipolar disorder: emerging diagnostic and treatment approaches

Children and adolescents who have bipolar disorder often are encountered in clinical settings and frequently require treatment with mood stabilizers and atypical antipsychotics. New screening and diagnostic tools are available to aid in the diagnosis of bipolar disorder in children and adolescents. Additional data supporting the use of mood stabilizers and atypical antipsychotics in this population also are emerging. Combinations of existing psychotropics remain the most effective treatment of pediatric bipolar disorder at this point. This article reviews the phenomenology and clinical characteristics of pediatric bipolar disorder and current approaches to pharmacotherapy. It is becoming apparent that bipolar disorder is often a chronic disorder in children and adolescents, much like diabetes, and is best managed with a combination of medications and psychosocial therapy.

Pharmacotherapy of children and adolescents with bipolar disorder

The identification and treatment of children and adolescents with a bipolar disorder is often challenging and difficult. Many of the psychotropic agents used to treat adults with bipolar disorder may also be-used to treat children and adolescents with these disorders. Further controlled trials using combination pharmacotherapy in children and adolescents with bipolar disorders are needed to advance the field of pediatric bipolarity and provide optimal care for these patients. There are multiple ongoing trials of mood stabilizers and atypical antipsychotics that will provide important controlled data that are currently lacking in the field.

Treatment Strategies for Myoclonic Seizures and Epilepsy Syndromes with Myoclonic Seizures

Despite the availability of numerous treatment options, the diagnosis and treatment of myoclonic seizures continue to be challenging. Based on clinical experience, valproate and benzodiazepines have historically been used to treat myoclonic seizures. However, many more treatment options exist today, and the clinician must match the appropriate treatment with the patient's epilepsy syndrome and its underlying etiology. Comorbidities and other medications must also be considered when making decisions regarding treatment. Rarely, some antiepileptic drugs may exacerbate myoclonic seizures. Most epileptic myoclonus can be treated pharmacologically, but some cases respond better to surgery, the ketogenic diet, or vagus nerve stimulation. Because myoclonic seizures can be difficult to treat, clinicians should be flexible in their approach and tailor therapy to each patient.

The use of mood stabilizers and atypical antipsychotics in children and adolescents with bipolar disorders

The clinical use of mood stabilizers and antipsychotics in children and adolescents with bipolar disorders has increased significantly over the past few years. These agents have multiple effects and interactions. This articles reviews the studies that support the use of mood stabilizers and atypical antipsychotics in children and adolescents with bipolar disorders and presents information on these agent's pharmacokinetics, dosing, and drug interactions.