Stereoselective pharmacokinetic and pharmacodynamic analysis of a CNS-active sulphamoylphenyl carbamate derivative.

3-Methylpentyl(4-sulphamoylphenyl)carbamate (MSPC) came as the most potent compound out of a new series of carbamates composed of phenyl-ethanol or branched aliphatic alcohols, and 4-benzenesulphonamide-carbamic acid. In this study, the anticonvulsant activity and pharmacokinetics (PKs) of MSPC-two individual enantiomers were comparatively analysed in rats as well as their carbonic anhydrase (CA) inhibition. The anticonvulsant activity of MSPC enantiomers was evaluated at the rat-maximal electroshock (MES) test, and their CA inhibition evaluated. (R)-MSPC had a 29% higher clearance and consequently, a lower plasma exposure area under the curve (AUC) than (S)-MSPC and racemic-MSPC. Nevertheless, (R)-MSPC had a better brain permeability than its (S)-enantiomer with brain-to-plasma-(AUC)-ratio (BPR) of 2.07 ((R)-enantiomer), 1.85 (racemate), and 0.79 ((S)-enantiomer). As a whole body (in vivo) pharmacodynamic (PD) measure, MSPC-anticonvulsant maximal electroshock seizure (MES) activity was less enantioselective than MSPC-CA inhibition. The lack of significant differences between racemic-MSPC and its individual enantiomers suggest that their anticonvulsant activity might be due to multiple mechanisms of action.

Serum protein binding of 25 antiepileptic drugs in a routine clinical setting: A comparison of free non-protein-bound concentrations.

OBJECTIVE: Given that only the free non-protein-bound concentration of an antiepileptic drug (AED) crosses the blood-brain barrier, entering the brain and producing an antiepileptic effect, knowledge and measurement of the free drug fraction is important. Such data are sparse, particularly for newer AEDs, and have arisen from the use of disparate methodologies and settings over the past six decades. We report on the protein binding of 25 AEDs that are available for clinical use, along with two pharmacologically active metabolites (carbamazepine-epoxide and N-desmethyl clobazam), using standardized methodology and under set conditions. METHODS: The protein binding of the various AEDs was undertaken in sera of 278 patients with epilepsy. Separation of the free non-protein-bound component was achieved by using ultracentrifugation (Amicon Centrifree Micropartition System) under set conditions: 500 µl serum volume; centrifugation at 1,000 g for 15 min, and at 25°C. Free and total AED concentrations were measured by use of fully validated liquid chromatography/mass spectroscopy (LC/MS) techniques. RESULTS: Gabapentin and pregabalin are non-protein-bound, whereas highly bound AEDs (≥88%) include clobazam, clonazepam, perampanel, retigabine, stiripentol, tiagabine, and valproic acid as well as the N-desmethyl-clobazam (89%) metabolite. The minimally bound drugs (<22%) include ethosuximide (21.8%), lacosamide (14.0%), levetiracetam (3.4%), topiramate, (19.5%) and vigabatrin (17.1%). Ten of the 25 AEDs exhibit moderate protein binding (mean range 27.7-74.8%). SIGNIFICANCE: These data provide a comprehensive comparison of serum protein binding of all available AEDs including the metabolites, carbamazepine-epoxide and N-desmethyl-clobazam. Knowledge of the free fraction of these AEDs can be used to optimize epilepsy treatment.

Design and Comparative Evaluation of the Anticonvulsant Profile, Carbonic-Anhydrate Inhibition and Teratogenicity of Novel Carbamate Derivatives of Branched Aliphatic Carboxylic Acids with 4-Aminobenzensulfonamide.

Epilepsy is one of the most common neurological diseases, with between 34 and 76 per 100,000 people developing epilepsy annually. Epilepsy therapy for the past 100+ years is based on the use of antiepileptic drugs (AEDs). Despite the availability of more than twenty old and new AEDs, approximately 30% of patients with epilepsy are not seizure-free with the existing medications. In addition, the clinical use of the existing AEDs is restricted by their side-effects, including the teratogenicity associated with valproic acid that restricts its use in women of child-bearing age. Thus, there is an unmet clinical need to develop new, effective AEDs. In the present study, a novel class of carbamates incorporating phenethyl or branched aliphatic chains with 6-9 carbons in their side-chain, and 4-benzenesulfonamide-carbamate moieties were synthesized and evaluated for their anticonvulsant activity, teratogenicity and carbonic anhydrase (CA) inhibition. Three of the ten newly synthesized carbamates showed anticonvulsant activity in the maximal-electroshock (MES) and 6 Hz tests in rodents. In mice, 3-methyl-2-propylpentyl(4-sulfamoylphenyl)carbamate(1), 3-methyl-pentan-2-yl-(4-sulfamoylphenyl)carbamate (9) and 3-methylpentyl, (4-sulfamoylphenyl)carbamate (10) had ED50 values of 136, 31 and 14 mg/kg (MES) and 74, 53, and 80 mg/kg (6 Hz), respectively. Compound (10) had rat-MES-ED50 = 13 mg/kg and ED50 of 59 mg/kg at the mouse-corneal-kindling test. These potent carbamates (1,9,10) induced neural tube defects only at doses markedly exceeding their anticonvuslnat-ED50 values. None of these compounds were potent inhibitors of CA IV, but inhibited CA isoforms I, II and VII. The anticonvulsant properties of these compounds and particularly compound 10 make them potential candidates for further evaluation and development as new AEDs.

Quality of life, mood and seizure control in patients with brain tumor related epilepsy treated with lacosamide as add-on therapy: A prospective explorative study with a historical control group.

OBJECTIVE: Brain tumor-related epilepsy (BTRE) is often drug resistant and patients can be forced to take polytherapy that can adversely affect their quality of life (QoL). Lacosamide (LCM) is a new antiepileptic drug (AED) used as adjunctive therapy in patients with partial seizures with or without secondary generalization, with a favorable pharmacokinetic profile that seems to be effective and well tolerated. Therefore it represents a possible therapeutic choice for patients with BTRE. We propose a prospective study with a historical control group to evaluate the effect of LCM as add-on therapy on seizure control and quality of life in patients with BTRE. This study has been designed to test the superiority of Lacosamide over Levetiracetam as an add-on. We compared a prospective cohort of 25 patients treated with Lacosamide with a historical control group (n=19) treated with Levetiracetam as an add-on. METHODS: We recruited 25 adult patients (M 18, F 7; mean age 41.9) affected by BTRE with uncontrolled partial-onset seizures treated with AED polytherapy. We added LCM as an add-on. Patients were evaluated at baseline, after 3months and at 6months. This population has been compared with a historical control group of 19 BTRE adult patients (M 13, F 6; median age 48.0, range: 28-70) with uncontrolled partial-onset seizures treated with LEV as add-on. The patients underwent QoL, mood and adverse events tests (Adverse Event Profile-AEP) and evaluation of seizure frequency. RESULTS: Twelve patients had high grade gliomas, and thirteen had low grade gliomas. During follow-up, thirteen patients underwent chemotherapy, three radiotherapy and five patients had disease progression. Nine patients had simple partial seizures, eight had complex partial seizures, and eight had secondary generalized seizures. Fifteen patients were in monotherapy and ten in polytherapy with AEDs. LCM was added up to reach the maximum dosage of 400mg/die (mean final dose 300mg/die). Four patients dropped out due to poor compliance and 1 for inefficacy. In the historical control group treated with LEV (mean final dose 2000mg/die) 12 patients had high-grade gliomas, and 7 had low grade gliomas. Thirteen patients were in monotherapy and 6 in polytherapy with AEDs. In the 22 patients evaluable of 25 patients treated with LCM, we observed at final follow-up 7 patients seizure free, 12 with a significant reduction of seizures≥50%, 2 stable and 1 patient with number of seizures increased. Mean seizure frequency at baseline compared with baseline period: the mean number of seizures significantly decreased from baseline (9.4) to final follow-up (1.2) (P=0.005). The Responder Rate was 86.4%. Comparing responder rate of 22 evaluable patients with LCM with responder rate of 19 patients with LEV we didn't observe significant differences (p=0.31). In our patients treated with LCM we didn't observe significant difference at 3 and 6months in QoL tests results; we observe a significant reduction in the mean score of Karnofsky Performance Status (KPS) and Barthel Index (BI) between baseline and 6months of follow-up (KPS p=0.003; BI p=0.007). No clinical side effects were observed. CONCLUSION: Comparing the LCM with the historical group treated with LEV in add-on, we observed that LCM seems to have a higher clinical efficacy than LEV. In our patients, we did not observe any significant changes in QoL tests, indicating stability in all quality of life domains explored, despite the objective worsening in their functional status. Although this is a small series with a relatively short follow-up, our data indicates that LCM in add-on in patients with BTRE appears to be as effective as LEV in add-on, without impact on mood and quality of life.

Pharmacokinetic-Pharmacodynamic Correlation and Brain Penetration of sec-Butylpropylacetamide, a New CNS Drug Possessing Unique Activity against Status Epilepticus.

sec-Butylpropylacetamide (SPD) is the amide derivative of valproic acid (VPA). SPD possess a wide-spectrum anticonvulsant profile better than that of VPA and blocks status epilepticus (SE) induced by pilocarpine and organophosphates. The activity of SPD on SE is better than that of benzodiazepines (BZDs) in terms of the ability to block SE when given 20-60 min after the beginning of a seizure. However, intraperitoneal (i.p.) administration to rats cannot be extrapolated to humans. Consequently, in the current study a comparative pharmacokinetic (PK)-pharmacodynamic analysis of SPD was conducted following i.p., intramuscular (i.m.), and intravenous (i.v.) administrations to rats. SPD brain and plasma levels were quantified at various times after dosing following i.p. (60 mg/kg), i.v. (60 mg/kg), and i.m. administrations (120 mg/kg) to rats, and the major PK parameters of SPD were estimated. The antiseizure (SE) efficacies of SPD and its individual stereoisomers were assessed in the pilocarpine-induced BZD-resistant SE model following i.p. and i.m. administrations to rats at 30 min after seizure onset. The absolute bioavailabilities of SPD following i.p. and i.m. administrations were 76% (i.p.) and 96% (i.p.), and its clearance and half-life were 1.8-1.5 L h(-1) kg(-1) and 0.5-1.7 h, respectively. The SPD brain-to-plasma AUC ratios were 1.86 (i.v.), 2.31 (i.p.), and 0.77 (i.m.). Nevertheless, the ED50 values of SPD and its individual stereoisomers were almost identical in the rat pilocarpine-induced SE model following i.p. and i.m. administrations. In conclusion, in rats SPD is completely or almost completely absorbed after i.m. and i.p. administration and readily penetrates into the brain. Consequently, in spite of PK differences, the activities of SPD in the BZD-resistant SE model following i.m. and i.p. administrations are similar.

Design and comparative anticonvulsant activity assessment of CNS-active alkyl-carbamoyl imidazole derivatives.

A novel series of carbamoyl derivatives of alkylimidazole has been designed and their anticonvulsant activity was comparatively evaluated in the mice- and rats-maximal-electroshock (MES), subcutaneous-metrazol (scMet) seizure tests and the mice-6Hz psychomotor (6Hz) models. The ten new designed molecules contain in their chemical structure imidazole, alkyl side-chain and carbamate as three potential active moieties. In spite of the close structural features of the carbamoyl imidazole derivatives only compounds 7, 8, 13 and 16 were active at the MES test with ED50 values ranging from 12 to 20mg/kg coupled with high protective index (PI=TD50/ED50) values of 4.1-7.3 after ip administration to rats. A similar phenomenon was observed in mice where compounds 7, 8, 9, 12 had MES-ED50 values of 14-26mg/kg. Compounds 7 and 13 also demonstrated anticonvulsant activity in the 6Hz model with ED50 values of 32 and 44mg/kg, respectively. As the most active entities, compounds 7, 8 followed by 13 and 16, thus offer an optimal efficacy-safety profile and consequently, might be promising candidates for development as new antiepileptics.

The potential of sec-butylpropylacetamide (SPD) and valnoctamide and their individual stereoisomers in status epilepticus.

sec-Butylpropylacetamide (SPD) is a one-carbon homologue of valnoctamide (VCD), a chiral constitutional isomer of valproic acid's (VPA) corresponding amide--valpromide. Racemic-SPD and racemic-VCD possess a unique and broad-spectrum antiseizure profile superior to that of VPA. In addition, SPD blocks behavioral and electrographic status epilepticus (SE) induced by pilocarpine and the organophosphates soman and paraoxon. Valnoctamide has similar activity as SPD in the soman-induced SE model. The activity of SPD and VCD against SE is superior to that of diazepam and midazolam in terms of rapid onset, potency, and ability to block SE when given 20 to 60 min after seizure onset. sec-Butylpropylacetamide and VCD possess two stereogenic carbons in their chemical structure and, thus, exist as a racemic mixture of four individual stereoisomers. The anticonvulsant activity of the individual stereoisomers of SPD and VCD was comparatively evaluated in several anticonvulsant rodent models including the benzodiazepine-resistant SE model. sec-Butylpropylacetamide has stereoselective pharmacokinetics (PK) and pharmacodynamics (PD). The higher clearance of (2R,3S)-SPD and (2S,3R)-SPD led to a 50% lower plasma exposure and, consequently, to a lower anticonvulsant activity compared to racemic-SPD and its two other stereoisomers. Racemic-SPD, (2S,3S)-SPD, and (2R,3R)-SPD have similar anticonvulsant activities and PK profiles that are better than those of (2R,3S)-SPD and (2S,3R)-SPD. Valnoctamide has a stereoselective PK with (2S,3S)-VCD exhibiting the lowest clearance and, consequently, a twice-higher plasma exposure than all other stereoisomers. Nevertheless, there was less stereoselectivity in VCD anticonvulsant activity, and each stereoisomer had similar ED50 values in most models. sec-Butylpropylacetamide and VCD stereoisomers did not cause teratogenicity (i.e., neural tube defect) in mice at doses 3-12 times higher than their anticonvulsant-ED50 values. This article is part of a Special Issue entitled "Status Epilepticus".

Pharmacodynamic and pharmacokinetic analysis of CNS-active constitutional isomers of valnoctamide and sec-butylpropylacetamide--Amide derivatives of valproic acid.

Valnoctamide (VCD) and sec-butylpropylacetamide (SPD) are CNS-active closely related amide derivatives of valproic acid with unique anticonvulsant activity. This study evaluated how small chemical changes affect the pharmacodynamics (PD; anticonvulsant activity and teratogenicity) and pharmacokinetics (PK) of three constitutional isomers of SPD [sec-butylisopropylacetamide (SID) and tert-butylisopropylacetamide (TID)] and of VCD [tert-butylethylacetamide (TED)]. The anticonvulsant activity of SID, TID, and TED was comparatively evaluated in several rodent anticonvulsant models. The PK-PD relationship of SID, TID, and TED was evaluated in rats, and their teratogenicity was evaluated in a mouse strain highly susceptible to teratogen-induced neural tube defects (NTDs). sec-Butylisopropylacetamide and TID have a similar PK profile to SPD which may contribute to their similar anticonvulsant activity. tert-Butylethylacetamide had a better PK profile than VCD (and SPD); however, this did not lead to a superior anticonvulsant activity. sec-Butylisopropylacetamide and TED did not cause NTDs at doses 4-7 times higher than their anticonvulsant ED50 values. In rats, SID, TID (ip), and TED exhibited a broad spectrum of anticonvulsant activity. However, combined anticonvulsant analysis in mice and rats shows SID as the most potent compound with similar activity to that of SPD, demonstrating that substitution of the isobutyl moiety in the SPD or VCD molecule by tert-butyl as well as a propyl-to-isopropyl replacement in the SPD molecule did not majorly affect the anticonvulsant activity.

Stereoselective anticonvulsant and pharmacokinetic analysis of valnoctamide, a CNS-active derivative of valproic acid with low teratogenic potential.

OBJECTIVE: Valnoctamide (VCD), a central nervous system (CNS)-active chiral constitutional isomer of valpromide, the corresponding amide of valproic acid (VPA), is currently undergoing phase IIb clinical trials in acute mania. VCD exhibits stereoselective pharmacokinetics (PK) in animals and humans. The current study comparatively evaluated the pharmacodynamics (PD; anticonvulsant activity and teratogenicity) and PK of the four individual stereoisomers of VCD. METHODS: The anticonvulsant activity of VCD individual stereoisomers was evaluated in several rodent anticonvulsant models including maximal electroshock, 6 Hz psychomotor, subcutaneous metrazol, and the pilocarpine-induced and soman-induced status epilepticus (SE). The PK-PD (anticonvulsant activity) relationship of VCD stereoisomers was evaluated following intraperitoneal administration (70 mg/kg) to rats. Induction of neural tube defects (NTDs) by VCD stereoisomers was evaluated in a mouse strain that was highly susceptible to teratogen-induced NTDs. RESULTS: VCD had a stereoselective PK, with (2S,3S)-VCD exhibiting the lowest clearance, and consequently a twice-higher plasma exposure than all other stereoisomers. Nervertheless, there was less stereoselectivity in VCD anticonvulsant activity and each stereoisomer had similar median effective dose (ED)50 values in most models. VCD stereoisomers (258 or 389 mg/kg) did not cause NTDs. These doses are 3-12 times higher than VCD anticonvulsant ED50 values. SIGNIFICANCE: VCD displayed stereoselective PK that did not lead to significant stereoselective activity in various anticonvulsant rodent models. If VCD exerted its broad-spectrum anticonvulsant activity using a single mechanism of action (MOA), it is likely that it would exhibit a stereoselective PD. The fact that there was no significant difference between racemic VCD and its individual stereoisomers suggests that VCD's anticonvulsant activity is due to multiple MOAs.

Enantioselective pharmacodynamic and pharmacokinetic analysis of two chiral CNS-active carbamate derivatives of valproic acid.

OBJECTIVE: 2-Ethyl-3-methylbutyl-carbamate (EMC) and 2-isopropylpentyl-carbamate (IPC) are among the most potent anticonvulsant carbamate derivatives of valproic acid. EMC and IPC are chiral compounds. Consequently, the aim of the current study was to comparatively evaluate the pharmacokinetic (PK) and pharmacodynamic (PD anticonvulsant activity) profile of EMC and IPC individual enantiomers. METHODS: The anticonvulsant activity of EMC and IPC individual enantiomers was evaluated in several anticonvulsant rodent models including maximal electroshock (MES), 6 Hz psychomotor, subcutaneous (pentylenetetrazole) (scMet), and the pilocarpine-induced and soman-induced status epilepticus (SE). The PK-PD relationship of EMC and IPC individual enantiomers was evaluated following intraperitoneal administration (50 mg/kg) to rats. Induction of neural tube defects (NTDs) was evaluated in a mouse strain that was highly susceptible to teratogen-induced NTDs. RESULTS: In mice and rats, (2S)-EMC exhibited anticonvulsant activity similar to that of racemic EMC in the MES and scMet tests, whereas in the 6 Hz test, racemic EMC was more potent than its two individual enantiomers. Racemic EMC exhibited a potent activity in the soman-induced SE model when administered 5 and 20 min after seizure onset with median effective dose (ED50 ) values of 33 and 48 mg/kg, respectively. (2R)-IPC and (2S)-IPC exhibited ED50 values similar to those of racemic IPC in the mouse and rat MES and scMet models. (2R)-IPC had similar ED50 values on the 6 Hz tests. Racemic IPC had an ED50 value of 107 mg/kg in the pilocarpine-induced SE model when given 30 min after seizure onset. Racemic EMC and IPC and their enantiomers had similar clearance (3.8-5.5 L/h/kg) and short half-life (<1 h). EMC and its enantiomers did not cause NTDs at doses 3-10 times higher than their anticonvulsant ED50 values. SIGNIFICANCE: EMC and IPC did not exhibit enantioselective PK, a fact that may contribute to their nonenantioselective activity in any of the anticonvulsant models. The nonsignificant difference between racemic EMC and racemic IPC and their enantiomers, suggests that their wide spectrum of anticonvulsant activity is likely to be caused by multiple mechanisms of action.

sec-Butyl-propylacetamide (SPD) and two of its stereoisomers rapidly terminate paraoxon-induced status epilepticus in rats.

OBJECTIVE: Organophosphates (OPs) are commonly used insecticides for agriculture and domestic purposes, but may also serve as nerve agents. Exposure to OPs result in overstimulation of the cholinergic system and lead to status epilepticus (SE), a life-threatening condition that is often resistant to treatment. SE is associated with significant neuronal damage, neurocognitive dysfunction, and the development of lifelong epilepsy. Therefore, rapid termination of SE and prevention of brain damage is of high interest. Here we tested the efficacy of sec-butyl-propylacetamide (SPD) and two of its individual stereoisomers, (2S,3S)-SPD and (2R,3R)-SPD, in discontinuing OP-induced seizures. SPD is a one carbon homolog of valnoctamide, a central nervous system (CNS)-active constitutional isomer of valproic acid (VPA) corresponding amide valpromide. METHODS: Rats were implanted with epidural telemetric electrodes to allow electrocorticography (ECoG) recording 24 h prior, during and 24 h after poisoning with the OP paraoxon (at a dose equivalent to 1.4 LD50 Median lethal dose). All rats were provided with antidotal treatment of atropine and toxogonin. Epileptic activity was measured using a novel automated system to evaluate the different effects of midazolam, SPD, and its individual stereoisomers in comparison to nontreated controls. RESULTS: Treatment with SPD or its individual stereoisomer (2S,3S)-SPD significantly shorten paraoxon-induced SE and reduced the duration of recorded pathologic activity after SE was terminated. (2S,3S)-SPD was superior to racemic-SPD in diminishing delayed pathologic epileptiform activity within the first 8 h after SE. SIGNIFICANCE: These results suggest SPD as an efficient drug for the rapid termination of SE and pathological epileptiform activity following OP poisoning, a strategy to reduce neuronal dysfunction and the risk for lifelong epilepsy.

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.

Investigation of the Roles of New Antiepileptic Drugs and Serum BDNF Levels in Efficacy and Safety Monitoring and Quality of Life: A Clinical Research.

OBJECTIVE: We aimed to determine the therapeutic drug monitoring (TDM) features and the relation to Brain-Derived Neurotrophic Factor (BDNF) of frequently used new antiepileptic drugs (NADs) including lamotrigine (LTG), oxcarbazepine (OXC), zonisamide (ZNS) and lacosamide (LCM). Moreover, we investigated their effect on the quality of life (QoL). METHODS: Eighty epileptic patients who had been using the NADs, and thirteen healthy participants were included in this cross-sectional study. The participants were randomized into groups. The QOLIE-31 test was used for the assessment of QoL. We also prepared and applied "Safety Test". HPLC method for TDM, and ELISA method for BDNF measurements were used consecutively. RESULTS: In comparison to healthy participants, epileptic participants had lower marriage rate (p=0.049), education level (p˂0.001), alcohol use (p=0.002). BDNF levels were higher in patients with focal epilepsy (p=0.013) and in those with higher education level (p=0.016). There were negative correlations between serum BDNF levels and serum ZNS levels (p=0.042) with LTGpolytherapy, serum MHD levels (a 10-monohydroxy derivative of OXC, p=0.041) with OXCmonotherapy. There was no difference in BDNF according to monotherapy-polytherapy, drugresistant groups, regarding seizure frequency. There was a positive correlation between total health status and QoL (p˂0.001). QOLIE-31 overall score (OS) was higher in those with OXCmonotherapy (76.5±14.5). OS (p˂0.001), seizure worry (SW, p=0.004), cognition (C, p˂0.001), social function (SF, p˂0.001) were different in the main groups. Forgetfulness was the most common unwanted effect. CONCLUSION: While TDM helps the clinician to use more effective and safe NADs, BDNF may assist in TDM for reaching the therapeutic target in epilepsy.

Antiepileptic Drug Therapy in Patients with Drug-Resistant Epilepsy.

Antiepileptic drug (AED) therapy starts with an accurate diagnosis of epilepsy and is followed by sequential drug trials. Seizure freedom is largely achieved by the first two drug trials; thus, epilepsy that cannot be controlled after appropriately conducted trials of the first two drugs is defined as drug-resistant epilepsy (DRE). It is still unclear which mode of pharmacotherapy, among monotherapy and polytherapy, shows better outcomes in cases of DRE. However, in a recent large hospital cohort study over past two decades, combination therapy was associated with a progressive increase in seizure-free rate than monotherapy in DRE. The benefits of polytherapy in the management of DRE might be related to the recent introduction of many new AEDs with different and novel mechanisms of action and better pharmacokinetic and tolerability profiles. These new AEDs were introduced to the market after they have proven their superiority over placebos in randomized controlled trials (RCTs) on add-on therapy in patients with DRE. Therefore, polytherapy including these new AEDs in the regimen is the approved mode of treatment for cases of DRE; this has prompted physicians to try various combinations of polytherapy to optimize the clinical outcomes. In addition, the significant discrepancies in AED responder rates between RCTs and real-world practice may support the importance of judicious use of new drugs in polytherapy by experienced epileptologists. Most experts now agree to the concept of "rational polytherapy" consisting of mechanistic combinations of AEDs exerting synergistic interactions and to the importance of continuing trials of different rational polytherapy regimens to improve the outcome of the core population of epilepsy patients in the long term.

Influence of propafenone on the anticonvulsant activity of various novel antiepileptic drugs in the mouse maximal electroshock model.

BACKGROUND: The main mechanism of action of propafenone (antiarrhythmic drug) involves the inhibition of the fast inward sodium current during phase 0 of the action potential. Sodium channel-blocking activity is also characteristic for some antiepileptic drugs. Therefore, it could be assumed that propafenone may also affect seizures. In the present study, we evaluated the effect of propafenone on the protective effect of oxcarbazepine, lamotrigine, topiramate and pregabalin against the maximal electroshock-induced seizures in mice. METHODS: Anticonvulsant activity of propafenone was assessed with the maximal electroshock seizure threshold (MEST) test. Influence of propafenone on the anticonvulsant activity of antiepileptic drugs was estimated in the mouse maximal electroshock model (MES). Drug-related adverse effects were determined in the chimney test (motor coordination) and passive-avoidance task (long-term memory). Brain concentrations of antiepileptics were assessed by fluorescence polarization immunoassay. RESULTS: Propafenone at doses 60-90mg/kg significantly increased the threshold of seizures, in turn at doses 5-50mg/kg did not affect this parameter. Administration of propafenone at the subthreshold dose of 50mg/kg increased antielectroshock activity of oxcarbazepine, topiramate and pregabalin, but not that of lamotrigine. As regards adverse effects, propafenone alone and in combination with antiepileptic drugs did not significantly impair motor coordination or long-term memory in mice. Propafenone (50mg/kg) significantly increased the brain level of pregabalin. Brain concentrations of topiramate and oxcarbazepine were not affected. CONCLUSION: Our findings show that propafenone has own anticonvulsant action and enhances efficacy of oxcarbazepine, topiramate and pregabalin, but not that of lamotrigine, at least in experimental condition.

Safety and tolerability profile of new antiepileptic drug treatment in children with epilepsy.

INTRODUCTION: Treatment of pediatric epilepsy requires a careful evaluation of the safety and tolerability profile of antiepileptic drugs (AEDs) to avoid or minimize as much as possible adverse events (AEs) on various organs, hematological parameters, and growth, pubertal, motor, cognitive and behavioral development. AREAS COVERED: Treatment-emergent AEs (TEAEs) reported in the literature 2000-2018 regarding second- and third-generation AEDs used in the pediatric age, with exclusion of the neonatal period that exhibits specific peculiarities, have been described on the basis of their frequency, severity/tolerability, and particular association with a given AED. EXPERT OPINION: Somnolence/sedation and behavioral changes, like irritability and nervousness, are among the most commonly observed TEAEs associated with almost all AEDs. Lamotrigine, Gabapentin, Oxcarbazepine, and Levetiracetam appear to be the best-tolerated AEDs with a ≤2% withdrawal rate, while Tiagabine and Everolimus are discontinued in up to >20% of the patients because of intolerable TEAEs. For some AEDs, literature data are scanty to draw a high-level evidence on their safety and tolerability profile. The reasons are: insufficient population size, short duration of treatments, or lack of controlled trials. A future goal is that of identifying clearer, easier, and more homogeneous methodological strategies to facilitate AED testing in pediatric populations.

Outcome of treatment changes in patients with drug-resistant chronic epilepsy: A tertiary center experience.

BACKGROUND: Previous studies suggest that changing patients' anti-epileptic drug regimen can reduce the frequency of seizures. The approval of new anti-epileptic drugs with different modes of action during the last decades has provided multiple options for the treatment of epilepsy, although the efficacy of these new drugs is controversial. We aimed to determine the effects of adding or changing to a previously untried anti-epileptic drug, including recently approved drugs, on the frequency of seizures in patients with drug-resistant epilepsy. METHODS: We analyzed treatment changes in drug-resistant patients at our outpatient clinic between 2010 and 2015. We classified patients' frequency of seizures after changes as freedom from seizures, ≥50% reduction, <50% reduction, no change, increase in seizures <50% or increase in seizures ≥50%. RESULTS: We analyzed 189 drug changes in 144 consecutive drug-resistant patients followed up for at least 6 months after the change; 138 changes involved administering newly marketed drugs: lacosamide (n=65), perampanel (n=30), eslicarbazepine (n=29), and retigabine (n=14). Changes resulted in freedom from seizures in 20 (13.9%) patients and in ≥50% decrease in frequency in 55 (38.2%). The drugs most commonly associated with significant improvement (freedom from seizures or ≥50% reduction) were lacosamide (39.3%), clobazam (11.2%), and levetiracetam (11.2%). CONCLUSIONS: In patients with drug-resistant epilepsy, sequential changes increase the possibility of seizure control, and newer anti-epileptic drugs offer additional options for effective changes. Best combinations must be chosen taking into account drug, epilepsy and patient features.

Clinical study of new and conventional antiepileptic drugs with newly diagnosed partial epilepsy / 中国临床药理学与治疗学

AIM: To compare the early response to the new and traditional antiepileptic drugs (AEDs) in the treatment of partial epilepsy. METHODS: Patients from neurology Department of Huzhou Central Hospital between January 2013 and June 2018 were included; outcomes included time to first seizure, time to treatment failure and 6-month, 1- and 2-year seizure-free rates were compared. RESULTS: A total of 250 patients with partial epilepsy were divided into carbamazepine (CBZ) group (n =62), levetiracetam (LEV) group (n = 67), oxcarbazepine (OXC) group (n = 63), and lamotrigine (LTG) group (n = 58). In terms of time to first seizure after monotherapy, CBZ and OXC were equivalent (P = 0.635), while CBZ was superi- or to LTG (P LTG > OXC > LEV, and CBZ was superior to OXC and LEV (all P 0.05). A total of 25 patients had adverse reactions; with CBZ (19.3%) more often than LTG (8.6%), OXC (7.9%), or LEV (4.5%). CONCLUSION: Treatment response to CBZ is superior compared to that of OXC and LEV, especially in the early stages of treatment, and equivalent to that of LTG, but the incidence of side effects is higher as well.

New antiepileptic drugs and women.

Since 1990, sixteen new antiepileptic drugs (AEDs) have been introduced. Most of these new AEDs have only been insufficiently studied with respect to women-specific aspects such as endogenous sex hormones, hormonal contraception, pregnancy, breastfeeding, or menopause. This is of concern because it has been shown for some of the new AEDs that these factors may have a clinically significant impact on their pharmacokinetics and seizure control. Also, new AEDs may affect hormone homeostasis and pass over into breast milk. The best studied of the new AEDs are lamotrigine, levetiracetam and oxcarbazepine. Although gabapentin and pregabalin are even more frequently used (due to their therapeutic effects in nonepileptic conditions), our understanding of these two drugs in relation to women's issues is surprisingly poor. Little to nothing is known about zonisamide, retigabine/ezogabine, lacosamide, perampanel and the other new AEDs. Nevertheless, many small studies and case series have been published on new AEDs and women-specific aspects. This review gives an overview on what is known today.

Effect of new antiepileptic drugs on bone metabolism in children:a Meta-analysis / 中国医师进修杂志

Objective To systematically evaluate the effects of new antiepileptic drugs on bone metabolism in children. Methods Chinese and English databases such as Pubmed, Cochrance Library, China Knowledge Network, Wanfang Knowledge Service Platform, and Weipu Chinese Journal Full-text Database were searched. The search time was limited for each database from the first issue to August 2018, and new anti-epileptic clinical trial of the effects of drugs on bone metabolism in children was selected. The literature was independently read by two reviewers. The effect size was extracted according to the inclusion and exclusion criteria, and the quality of the study was evaluated. The system evaluation (Meta analysis) was performed using Revman 5.3 software. Results A total of 526 cases in the experimental group (children taking antiepileptic drugs) and 478 cases in the control group (healthy children or children without taking antiepileptic drugs) were included in 16 pieces of literatures. Meta-analysis showed that there was no significant difference in bone mineral density between experimental group and control group ( SMD＝-0.03, 95% CI :-0.17-0.10, P＝0.62). As for bone turnover markers, there was significant differences in serum total alkaline phosphatase (ALP) between the two groups ( SMD＝0.19, 95% CI : 0.03- 0.36, P＝0.02), while there were no significant differences in serum calcium, serum phosphorus, serum bone specific alkaline phosphatase, serum vitamin D and the ratio of deoxypyridinoline andcreatinine (DPD/Cr). Conclusions The new antiepileptic drugs have no effect on bone mineral density. In the aspect of bone turnover markers, the serum total alkaline phosphatase of the children taking the new antiepileptic drugs is higher, but has no effect on other bone turnover markers.