Comparative retention rates and long-term tolerability of new antiepileptic drugs.

OBJECTIVE: Retention rates of five new anti-epileptic medications (AEDs) were compared in order to evaluate their long-term tolerability and efficacy. METHOD: We acquired the retention data on levetiracetam (LEV), lamotrigine (LTG), oxcarbazepine (OXC), topiramate (TPM), and zonisamide (ZNS) from the electronic database. The data included patient's age, gender, seizure type, current and previous medications, dosage, main reasons for discontinuation, and duration of therapy. The retention rates of these AEDs were evaluated at 4, 12, 24, 52, and 104 weeks. RESULTS: A total of 828 new AED exposures were obtained (LEV=196, LTG=251, OXC=97, TPM=156, ZNS=128) from patients with partial or generalized epilepsy. At 2 years, retention rate was highest with LTG (74.1%), followed by ZNS (60.2%), OXC (58.8%), LEV (53.6%), and TPM (44.2%). When these AEDs were discontinued, it was mainly due to inefficacy (29.5%) and sedating side-effects (20.5%), and commonly within 6 months into therapy. Several important AED specific side-effects leading to discontinuation were identified, including behavioral or irritability from LEV, rash from LTG and OXC, nausea from OXC and ZNS, hyponatremia from OXC, and kidney stones from TPM and ZNS. CONCLUSION: Comparing retention rates of new AEDs can provide useful insight into their tolerability and efficacy. This study showed highest retention rate with LTG, which was significantly different from ZNS (p=0.0025), LEV (p<0.0001), OXC (p=0.0024), and TPM (p<0.0001). Beside ineffectiveness, other leading causes of discontinuation were adverse behavioral effects with LEV, rash with LTG and OXC, and sedation for TPM and ZNS.     

How can antiepileptic drugs affect bone mass, structure and metabolism? Lessons from animal studies.

Patients with epilepsy, treated with antiepileptic drugs (AEDs) are at increased risk of fractures. Although several commonly used AEDs reduce bone mass in patients, the mechanisms are only scarcely known. In this review, we focus on the usefulness of animal models to explore the skeletal effects of AEDs. Moreover, we report our findings from a recent study comparing the effect of levetiracetam (LEV), phenytoin (PHT) and valproate (VPA) on various aspects of bone health in actively growing female rats. Our data indicate that these AEDs act differently on bone mass, structure and metabolism. A novel finding is that LEV reduces bone strength and bone formation without altering bone mass. Based on these results we propose that epidemiological fracture studies of patients treated with LEV are needed, and that these patients should be evaluated regularly to identify possible bone-related side effects.     

Comparison of levetiracetam and oxcarbazepine monotherapy among Korean patients with newly diagnosed focal epilepsy: A long‐term,randomized, open‐label trial

This open‐label, multicenter, randomized phase IV trial (NCT01498822) of noninferiority design compared the long‐term effectiveness, safety, and tolerability of levetiracetam (LEV) monotherapy with those of oxcarbazepine (OXC) monotherapy in adults with newly diagnosed focal epilepsy. Korean patients (16–80 years), with ≥2 unprovoked focal seizures in the year preceding the trial, who had not taken any antiepileptic drugs (AEDs) in the last 6 months, were randomized to receive LEV or OXC (1:1). Effectiveness, safety, and tolerability were assessed over a 50‐week period. Treatment failure rates (per protocol set) were 15/118 (12.7%) in the LEV‐treated group and 30/128 (23.4%) in the OXC‐treated group, an absolute difference of ?10.7% (95% confidence interval [CI] ?20.2, ?1.2). Because the upper 95% CI limit was less than the pre‐specified noninferiority margin of 15%, LEV was considered noninferior to OXC. Twenty‐four‐week and 48‐week seizure freedom rates were 53.8% and 34.7% for LEV vs. 58.5% and 40.9% for OXC. Both LEV and OXC were well tolerated, with 8.7% and 8.6% of patients reporting serious treatment‐emergent adverse events, respectively. By comparing LEV with OXC, another newer AED, LEV can be considered a useful option as initial monotherapy for patients with newly diagnosed focal epilepsy.     

Long-term retention rates of new antiepileptic drugs in adults with chronic epilepsy and learning disability

We compared the long-term retention rates of several newly licensed antiepileptic drugs (AEDs) in a residential community of adults with chronic epilepsy and learning disability. Data relating to duration of therapy, maximum dose, and tolerability of six new AEDs-gabapentin (GBP), lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), tiagabine (TIA), and topiramate (TPM)-were collected. Drug retention at 2 years was 85% (OXC), 57% (LTG), 56% (LEV), 45% (TPM), 24% (TIA) and 15% (GBP). OXC was used mainly as a substitute for carbamazepine. LTG, LEV, and TPM were all associated with retention rates higher than those of GBP or TIA. TPM had the highest rate of adverse event development at the maximum tried dose (60%), whereas LEV had the lowest (16%). Experience from this single epilepsy community study indicated limited impact for GBP or TIA but higher retention of OXC, LEV, LTG, and TPM in patients with chronic epilepsy and learning disability.     

Effects of new antiepileptic drugs on circulatory markers for vascular risk in patients with newly diagnosed epilepsy

Although it is well documented that long‐term therapy with older antiepileptic drugs (AEDs) leads to an increase in risk for atherosclerosis, there has been only limited information regarding the vascular risk in patients who are treated with new AEDs. We therefore conducted a prospective longitudinal study to assess the potential effects of new AEDs on the circulatory markers for vascular risk in patients with newly diagnosed epilepsy. We recruited adult patients with epilepsy who began to receive monotherapy with one of the new AEDs, including levetiracetam (LEV), oxcarbazepine (OXC), and topiramate (TPM). Circulatory markers of vascular risk were measured twice before and after 6 months of AED monotherapy. A total of 109 patients completed the study (LEV, n = 40; OXC, n = 40; TPM, n = 29). Six months of monotherapy resulted in significant increases in low‐density lipoprotein cholesterol (LEV, from 90.2 to 98.5 mg/dl, 9.2% increase, p = 0.025; OXC, from 96.5 to 103.2 mg/dl, 7.0% increase, p = 0.049), homocysteine (LEV, from 7.9 to 10.4 μm , 31.6% increase, p = 0.001; OXC, from 8.7 to 11.5 μm , 32.2% increase, p < 0.001; TPM, from 8.3 to 12.3 μm , 48.2% increase, p < 0.001), apolipoprotein B (LEV, from 63.6 to 77.4 mg/dl, 21.7% increase; OXC, from 67.0 to 83.2 mg/dl, 24.2% increase; TPM, from 66.7 to 84.4 mg/dl, 26.5% increase; all p < 0.001), and apolipoprotein B/apolipoprotein A1 ratio (LEV, from 0.51 to 0.61, 19.6% increase; OXC, from 0.52 to 0.67, 28.8% increase; TPM, from 0.50 to 0.67, 34.0% increase; all p < 0.001). Serum apolipoprotein A1 and folate were significantly decreased in TPM (from 139.1 to 132.1 mg/dl, 5.0% decrease, p = 0.014) and OXC (from 8.1 to 6.4 ng/ml, 21.0% decrease, p = 0.046) groups, respectively. There were no significant changes in total cholesterol, triglyceride, high‐density lipoprotein cholesterol, lipoprotein(a), and vitamin B12 in all three groups. Our findings suggest that treatment with some new AEDs might be associated with alterations in circulatory markers of vascular risk, which could contribute to the acceleration of atherosclerosis and increased risk of vascular diseases.     

Levetiracetam, phenytoin, and valproate act differently on rat bone mass, structure, and metabolism

PURPOSE: Long-term treatment with antiepileptic drugs (AEDs) is associated with increased risk of fractures. Phenytoin (PHT) and valproate (VPA) have both been suggested to influence bone health, whereas levetiracetam (LEV) is scarcely studied. The present study compares the effect of these AEDs on bone mass, biomechanical strength, and bone turnover in rats. METHODS: Female rats received PHT (50 mg/kg), VPA (300 mg/kg), or LEV (50 and 150 mg/kg) for 90 days. Dissected femurs were analyzed using dual energy x-ray absorptiometry (DXA), three-point cantilever bending, and histomorphological evaluation. Serum levels of biochemical bone turnover markers were monitored using immunoassay quantification. RESULTS: PHT and VPA reduced bone mineral density (BMD) and content (BMC) in one or more bone compartments, whereas LEV did not. VPA induced increased bone turnover, whereas modest changes were observed for PHT. Interestingly, low-dose LEV was associated with reduced biomechanical strength of the femoral neck (mainly trabecular bone). In addition, low-dose LEV treatment resulted in significantly reduced levels of serum osteocalcin, a marker of bone formation. Histomorphological analyses indicated increased retention of cartilage remnants at the growth plate metaphysis of rats treated with low-dose LEV vs. controls. CONCLUSIONS: PHT, VPA, and LEV exert differential effects on bone mass and strength, suggesting different mechanisms of action. The weakening effect of low-dose LEV on the femoral neck, despite a constant BMD, suggests a primary effect on bone quality. These findings warrant further human studies of possible adverse effects of LEV on bone development and growth, particularly in children and adolescents.     

Basic Science

Jarogniew J. Luszczki , Marta M. Andres , Piotr Czuczwar , Anna Cioczek-Czuczwar , Neville Ratnaraj , Philip N. Patsalos , and Stanislaw J. Czuczwar
Approximately 30% of patients with epilepsy do not experience satisfactory seizure control with current front-line antiepileptic drug (AED) monotherapy and often require polytherapy. The potential usefulness of AED combinations, in terms of efficacy and adverse effects, is therefore of major importance. The present study sought to identify potentially useful AED combinations with levetiracetam (LEV), recently introduced as an effective AED for refractory partial seizures. The mouse maximal electroshock (MES)-induced seizure model was investigated with regard to the anticonvulsant effects of carbamazepine (CBZ), phenytoin, phenobarbital (PB), valproate, lamotrigine, topiramate (TPM), and oxcarbazepine (OXC), administered singly and in combination with LEV. Acute adverse effects were ascertained by use of the chimney test, evaluating motor performance, and the passive avoidance task, assessing long-term memory. Brain AED concentrations were determined to ascertain any pharmacokinetic contribution to the observed antiseizure effect. LEV in combination with TPM exerted supraadditive (synergistic) interactions in the MES test. Likewise, the combinations of LEV with CBZ and OXC were supraadditive in this test. In contrast, all other LEV/AED combinations displayed additivity. Furthermore, none of the investigated combinations altered motor performance and long-term memory. LEV brain concentrations were unaffected by concomitant AED administration, and LEV had no significant effect on brain concentrations of concomitant AEDs. These preclinical data would suggest that LEV in combination with TPM is associated with beneficial anticonvulsant pharmacodynamic interactions. Similar, but less profound effects were seen with OXC and CBZ.     

Levetiracetam or oxcarbazepine as monotherapy in newly diagnosed benign epilepsy of childhood with centrotemporal spikes (BECTS): an open-label, parallel group trial

To evaluate the efficacy and tolerability of levetiracetam or oxcarbazepine as monotherapy in children with newly diagnosed benign epilepsy with centrotemporal spikes (BECTS). Twenty-one children (11 males, 10 females), aged between 5 and 13 years (mean 10.5 years), and 18 (10 M, 8 F), aged between 3.3 and 14 years (mean 8.4 years), were randomised to receive monotherapy with levetiracetam or oxcarbazepine, respectively. LEV was titrated up to 20-30 mg/kg/once or twice a day, and OXC up to 20-35 mg/kg once or twice a day. Thirty-nine consecutive children (21 males, 18 females), aged between 3.3 and 14 years (mean 10.7 years), were recruited into the study. Twenty-one were randomised on LEV (11 male, 10 female; mean age 10.5 years), and 18 on OXC (10 male, 8 female; mean age 8.4 years). After a mean follow-up period of 18.5 months (range 12-24 months), 19 out of 21 patients (90.5%) on levetiracetam, and 13 out of 18 (72,22%) on oxcarbazepine did not have further seizures. Mean serum level of LEV was 4.1 microg/ml (range 1.3-9.0), and of OXC was 15.2 microg/ml (range 4.2-27.5). Adverse side effects on LEV were reported in 3 children (14.3%), represented by mild and transient decreased appetite (2) and cephalalgia (1). They were reported on OXC in 2/18 (11.1%), including headache (1), and sedation (1). These preliminary data from an open, parallel group study suggest that levetiracetam and oxcarbazepine may be potentially effective and well tolerated drugs for children with BECTS who require treatment.     

Pharmacodynamic and pharmacokinetic characterization of interactions between levetiracetam and numerous antiepileptic drugs in the mouse maximal electroshock seizure model: an isobolographic analysis

PURPOSE: Approximately 30% of patients with epilepsy do not experience satisfactory seizure control with antiepileptic drug (AED) monotherapy and often require polytherapy. The potential usefulness of AED combinations, in terms of efficacy and adverse effects, is therefore of major importance. The present study sought to identify potentially useful AED combinations with levetiracetam (LEV) METHODS: With isobolographic analysis, the mouse maximal electroshock (MES)-induced seizure model was investigated with regard to the anticonvulsant effects of carbamazepine (CBZ), phenytoin, phenobarbital (PB), valproate, lamotrigine, topiramate (TPM), and oxcarbazepine (OXC), administered singly and in combination with LEV. Acute adverse effects were ascertained by use of the chimney test evaluating motor performance and the step-through passive-avoidance task assessing long-term memory. Brain AED concentrations were determined to ascertain any pharmacokinetic contribution to the observed antiseizure effect. RESULTS: LEV in combination with TPM, at the fixed ratios of 1:2, 1:1, 2:1, and 4:1, was supraadditive (synergistic) in the MES test. Likewise, the combination of LEV with CBZ (at the fixed ratio of 16:1) and LEV with OXC (8:1 and 16:1) were supraadditive. In contrast, all other LEV/AED combinations displayed additivity. Furthermore, none of the investigated LEV/AED combinations altered motor performance and long-term memory. LEV brain concentrations were unaffected by concomitant AED administration, and LEV had no significant effect on brain concentrations of concomitant AEDs. CONCLUSIONS: These preclinical data would suggest that LEV in combination with TPM is associated with beneficial anticonvulsant pharmacodynamic interactions. Similar, but less profound effects were seen with OXC and CBZ.     

Impact of mood stabilizers and antiepileptic drugs on cytokine production in-vitro

Changes within the immune system have been reported to contribute to the pathophysiology of bipolar disorder and epilepsy. Interestingly, overlapping results regarding the cytokine system have been found for both diseases, namely alterations of interleukins IL-1β, IL-2, IL-4, IL-6, and tumor necrosis factor-α (TNF-α). However, the effect of mood stabilizers and antiepileptic drugs (AEDs) on these cytokines has not been systematically evaluated, and their effect on IL-17 and IL-22, other immunologically important cytokines, has not been reported. Therefore, we systematically measured levels of IL-1β, IL-2, IL-4, IL-6, IL-17, IL-22 and TNF-α in stimulated blood of 14 healthy female subjects in a whole blood assay using the toxic shock syndrome toxin TSST-1 as stimulant. Blood was supplemented with the mood stabilizers or antiepileptic drugs primidone (PRM), carbamazepine (CBZ), levetiracetam (LEV), lamotrigine (LTG), valproic acid (VPA), oxcarbazepine (OXC), topiramate (TPM), phenobarbital (PB), lithium, or no drug. IL-1β production was significantly decreased by PRM, CBZ, LEV, LTG, OXC, PB and lithium. IL-2 significantly decreased by PRM, CBZ, LEV, LTG, VPA, OXC, TPM and PB. IL-22 significantly increased by PRM, CBZ, LEV, OXC, TPM and lithium and decreased by VPA. TNF-α production significantly decreased under all applied drugs. The mechanism of action and side effects of mood stabilizers and AEDs may involve modulation of IL-1β, IL-2, IL-22 and TNF-α signaling pathways. IL-22 may be a research target for specific therapeutic effects of mood stabilizers and AEDs. These drugs might influence cytokine production by modulating ion channels and γ-aminobutyric acid (GABA) receptors of immune cells.     

An In Vitro Study of New Antiepileptic Drugs and Astrocytes

Summary:  Purpose: The aim of our research was to study some biochemical modifications elicited in primary rat astrocyte cultures by treatment with gabapentin (GBP), carbamazepine (CBZ), lamotrigine (LTG), topiramate (TPM), oxcarbazepine (OXC), tiagabine (TGB), and levetiracetam (LEV), commonly used in the treatment of epilepsy. We investigated the biologic effects of these anticonvulsants (AEDs) at concentrations of 1, 10, 50, and 100 μg/ml.
Methods: The study was performed by examining cell viability (MTT assay), cell toxicity [lactate dehydrogenase (LDH) release in the medium], glutamine synthetase (GS) activity, reactive oxygen species (ROS) production, lipoperoxidation level (malondialdehyde; MDA), and DNA fragmentation (COMET assay). The level of the expression of 70-kDa heat-shock protein (HSP70) and inducible nitric oxide synthase (iNOS) as oxidative stress–modulated genes also was determined.
Results: Our experiments indicate that CBZ, TPM, and OXC induce stress on astrocytes at all concentrations. GBP, LTG, TGB, and LEV, at low concentrations, do not significantly change the metabolic activities examined and do not demonstrate toxic actions on astrocytes. They do so at higher concentrations.
Conclusions: Most AEDs have effects on glial cells and, when used at an appropriate cell-specific concentrations, may be well tolerated by cortical astrocytes. However, at higher concentrations, GBP, LTG, TGB, and LEV seem to be better tolerated than are CBZ, TPM, and OXC. These findings may reveal novel ways of producing large numbers of new AEDs capable of reducing the extent of inflammation, neuronal damage, and death under pathological conditions such as epilepsy and/or traumatic brain injury.     

Seizure-free outcome in randomized add-on trials of the new antiepileptic drugs

PURPOSE: The goal of this study is to (1) provide clinically useful, previously unpublished comparative analyses of seizure-freedom rates for newer antiepileptic drugs (AEDs), and (2) recommend a standard for data presentation and analysis. METHODS: Data were reviewed from placebo-controlled adjunctive trials in refractory patients of gabapentin (GPN), lamotrigine (LTG), topiramate (TOP), tiagabine (TGB), oxcarbazepine (OXC), levetiracetam (LEV), zonisamide (ZNS), and pregabalin (PGB). Seizure-freedom analyses in these publications, if included at all, consistently included both patients who completed the trial, and those who dropped out prior to completion (last observation carried forward, LOCF). This has the potential to increase reported seizure-free outcomes. Pharmaceutical companies were contacted for the provision of unpublished seizure-free data in the patients who completed the entire study. RESULTS: In most cases, LOCF analysis produced a higher rate of seizure freedom compared to complete analysis. A total of 0%-1.1% of the LOCF population was seizure-free in the GPN trials (complete data not available). For the remaining AEDs, seizure-freedom results in the LOCF versus complete populations were: 0.7% versus 0.8% (LTG trial); 12% versus 2.6% (OXC trial); 3.6%-6.4% versus 3.9%-7.1% (LEV trial); 3.7%-7.9% versus 1.3%-1.4% (PGB trial); and 6.0% versus 3.0% (ZNS trial, minus titration period). CONCLUSIONS: By employing LOCF, a clinically unrealistic picture of seizure-free rates may be reported. Access to complete data is informative, as it includes only those patients who were able to tolerate the drug at doses that produced seizure freedom. Ideally, data from both ITT and complete analyses should be made available.     

Preliminary evidence for gender effects of levetiracetam monotherapy duration on bone health of patients with epilepsy

Enzyme-inducing antiepileptic drugs AEDs have adverse effects on bone mineral density (BMD), whereas studies on levetiracetam (LEV), a nonenzyme-inducing agent, have showed conflicting results. The aim of this study was to further elucidate the role of LEV in bone health. A sample of forty-six patients with epilepsy (mean age: 35.7 years, range: 20.2–64.2 years, 39.1% males) on LEV monotherapy for at least one year (range: 1.5–14.5 years, median 5.5 years) underwent femoral neck (FN) and lumbar spine (LS) BMD measurements. The T- and Z-scores were calculated. Results showed that 15.2% of the patients were identified with osteopenia and none with osteoporosis. Pearson's correlations revealed a negative but not significant association of LEV duration with bone-related measurements (range of rhos: from − 0.004 to − 0.23), except for LS T-scores. In terms of FN BMD measurements, Z-scores, and T-scores, longer LEV therapy duration had adverse but not significant effects on bone health after adjusting for age and gender. With regard to LS BMD measurements, Z-scores, and T-scores, men taking LEV for at least 5.5 years had better, although not significant, bone health compared with men with shorter LEV exposure, after adjusting for age. The opposite was found in women, although differences did not reach significance. These preliminary results are indicative of a differential effect of LEV therapy duration in men and women, which could presumably account for the incongruity of the already published studies. Also, LS assessments were more sensitive to these gender differences. Future larger studies should validate these results.     

Comparison of the efficacy and tolerability of new antiepileptic drugs: what can we learn from long‐term studies?

OBJECTIVE: A review of long-term open-label studies was performed with the aim of detecting differences in efficacy and/or tolerability of new antiepileptic drugs (AEDs). METHODS: From more than 500 open studies conducted to evaluate the efficacy and tolerability of gabapentin (GBP), lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), pregabalin (PGB), tiagabine (TGB), topiramate (TPM) or zonisamide (ZNS), we selected all studies that reported or allowed us to calculate the number of patients who achieved seizure freedom for 6 months and/or the number of patients withdrawing for adverse effects and/or the number or percentage of patients continuing treatment after 1 year. RESULTS: No studies were found in which this information was available for OXC, PGB, TGB or ZNS. The number of patients who achieved seizure freedom for 6 months was reported in four studies each for GBP and TPM, five studies for LTG, and eight studies for LEV. The best efficacy profile using this end point was found for LEV, followed by TPM, LTG, and GBP. Twenty-two studies reported the number of patients withdrawing due to adverse effects. LEV was the best-tolerated AED, a little ahead of LTG, and significantly better than GBP or TPM . TPM was by far the least well-tolerated drug. Information concerning patients continuing treatment after 1 year was reported in two GBP studies, two TPM studies, six LEV studies and five LTG studies. GBP had a very low retention rate (between 20% and 25% of patients continued the drug), while TPM and LTG had a retention rate of 40-60% and LEV had a retention rate of 60-75%. CONCLUSION: One limitation of these rankings is that their statistical value is limited because of the indirect nature of the comparisons. Anyhow, this review covers the main studies published thus far on this subject and provides full updated information on the current literature about these drugs.     

DIZZYNET 2018: visions and perspectives of future vestibular research

The optimal combination of antiepileptic drugs (AEDs) for the treatment of refractory partial-onset epilepsy is a perpetual point of debate. While several network meta-analyses (NMAs) have been published, conclusions remain controversial, especially since newer AEDs have been introduced. In our review, we included the newer AEDs to evaluate the comparative efficacy and safety of AEDs for the treatment of refractory partial-onset epilepsy. We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials (Cochrane Library 2017, Issue 1) from their inception to February 18, 2017. The risk of bias in the included randomized controlled trials (RCTs) was evaluated according to the Cochrane Collaboration’s risk of bias tool. An NMA was performed with a Bayesian random-effects model, and we used the surface under the cumulative ranking curve to detect the optimal AEDs. Seventy-six RCTs with 17 AEDs and 20,711 patients were included in the NMAs, which showed that Brivaracetam (BRV), Levetiracetam (LEV), Oxcarbazepine (OXC), Topiramate, Vigabatrin (VGB), and Valproate (VPA) had a greater likelihood of allowing patients to achieve seizure freedom. We also found that LEV was associated with a lower withdrawal rate due to adverse effects than Lacosamide, Eslicarbazepine acetate, OXC, Pregabalin, and Retigabine. LEV, VGB, VPA, and BRV emerged as the agents with the best combination of properties when considering the efficacy and safety outcomes based on the full double-blind treatment period. However, it is critical to perform RCTs and to obtain prospective data from representative cohort studies.     

Gewichtsveränderungen unter Antiepileptikagabe

Antiepileptic drugs (AED) are usually taken for a number of years. Therefore, long-term tolerability is of great importance for the choice of an AED. Weight change is a highly relevant side effect and can be associated with increased morbidity and mortality. Unfortunately, several AEDs and especially some of the newer AEDs induce weight changes. Weight gain has been observed with valproate (VPA) and pregabalin (PGB) but also with gabapentin (GBP) and questionably with carbamazepine (CBZ). Weight loss, on the other hand, has been associated with long-term treatment with topiramate (TPM), zonisamide (ZNS), felbamate (FBM) and was also reported for rufinamide (RFM) and stiripentole (STP). Lamotrigine (LTG), phenytoine (PHT), the barbiturates, levetiracetam (LEV), lacosamide (LCM), and oxcarbazepine (OXC) are considered to have no systematic effect on body weight. The weight change observed was frequently associated with a change in appetite and food consumption in the same direction. Genetic factors are likely relevant for the AED-related weight change.     

New antiepileptic drugs in practice – how do they perform in the real world?

Most large-scale clinical trials of antiepileptic drugs (AEDs) are undertaken for regulatory purposes and generate basic data supporting the efficacy and safety of a new treatment. They do not, however, provide all the information required for physicians to know how well the drug will work in clinical practice. One valuable approach to generating more clinically meaningful information is to assess AED treatment retention rates, which reflect the combination of efficacy and tolerability in the real world, and have historically been low. Long-term retention rate data are available for levetiracetam (LEV), topiramate, gabapentin, and lamotrigine, and these data suggest that LEV is more likely to retain patients than other new AEDs. In a recent tertiary care study involving mainly refractory patients, 11% of participants became seizure-free on LEV and nearly two-thirds were retained on long-term treatment. High seizure freedom rates and good tolerability reported with LEV in clinical trials thus appear to translate into improved treatment retention rates in clinical practice.