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1.
Eur J Drug Metab Pharmacokinet ; 49(4): 437-447, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38709450

RESUMEN

BACKGROUND AND OBJECTIVES: A substantial inter-individual variability has been observed in the pharmacokinetics of lamotrigine. The aim of the study was to investigate the impact of genetic polymorphism of the metabolizing enzymes (UGT2B7, UGT1A4) and transporter (ABCG2) on the pharmacokinetics and therapeutic efficacy of lamotrigine in patients with epilepsy. METHODS: The genetic analysis of single-nucleotide polymorphisms was conducted using polymerase chain reaction sequence. High-performance liquid chromatography/tandem mass spectrometry was employed to measure the plasma concentrations of lamotrigine. The efficacy of lamotrigine was assessed by evaluating the reduction rate of epileptic seizure frequency. RESULTS: This study included a cohort of 331 patients who were treated with lamotrigine as monotherapy. A linear correlation was observed between the lamotrigine concentration and daily dose taken (r = 0.58, p < 2.2e-16). Statistically significant differences were found in both the median plasma concentration and dose-adjusted concentration (C/D ratio) when comparing the ineffective to the effective group (p < 0.05). Multivariate analysis showed that UGT1A4 rs2011425, ABCG2 rs2231142 polymorphisms and age had a significant relationship with the lamotrigine concentrations (p < 0.05). Age was a predictive factor for C/D ratio (p < 0.001). Lamotrigine concentration and weight were good predictive factors for effective seizure outcomes (odds ratio [OR] = 0.715, 95% CI 0.658-0.776, p < 0.001; OR = 0.926, 95% CI 0.901-0.951, p < 0.001, respectively). The cut-off values of lamotrigine trough concentrations for clinical outcomes in the age-related groups were determined as 2.49 µg/ml (area under the receiver-operating characteristic curve [AUC]: 0.828, 95% CI 0.690-0.966), 2.70 µg/ml (AUC: 0.805, 95% CI 0.745-0.866) and 3.25 µg/ml (AUC: 0.807, 95% CI 0.686-0.928) for the adult group, adolescent group, and toddler and school-age group, respectively. CONCLUSIONS: UGT1A4 rs2011425 and ABCG2 rs2231142 were correlated with lamotrigine concentrations. Lower lamotrigine trough concentration was found in the ineffective group and the troughs were associated with seizure outcomes.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Anticonvulsivantes , Epilepsia , Glucuronosiltransferasa , Lamotrigina , Proteínas de Neoplasias , Polimorfismo de Nucleótido Simple , Humanos , Lamotrigina/farmacocinética , Lamotrigina/uso terapéutico , Lamotrigina/administración & dosificación , Glucuronosiltransferasa/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Masculino , Femenino , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/uso terapéutico , Adulto , Persona de Mediana Edad , Adulto Joven , Proteínas de Neoplasias/genética , Adolescente , Anciano , Niño , Resultado del Tratamiento , Estudios de Cohortes
2.
Artículo en Inglés | MEDLINE | ID: mdl-38762161

RESUMEN

OBJECTIVE: Increasing evidence suggests that the physiological changes of pregnancy may impact pharmacokinetics of antiseizure medications (ASM), and this may affect treatment outcomes. The aim of this study was to quantify the pregnancy impact on the ASM pharmacokinetics. METHODS: A systematic literature search was conducted in PubMed/EMBASE in November 2022 and updated in August 2023 for studies comparing levels of ASM in the same individuals during pregnancy and in the preconception/postpartum period. Alteration ratios between the 3rd trimester and baseline were estimated. We also performed a random-effects meta-analysis calculating between-timepoint differences in mean differences (MDs) and 95% confidence intervals (95%CIs) for dose-adjusted plasma concentrations (C/D ratios). Study quality was assessed using the ClinPK guidelines. RESULTS: A total of 65 studies investigating 15 ASMs in 674 pregnancies were included. The largest differences were reported for lamotrigine, oxcarbazepine and levetiracetam (alteration ratio 0.42, range 0.07-2.45, 0.42, range 0.08-0.82 and 0.52, range 0.04-2.77 respectively): accordingly, C/D levels were lower in the 3rd trimester for lamotrigine, levetiracetam and the main oxcarbazepine metabolite monohydroxycarbazepine (MD = -12.33 × 10-3, 95%CI = -16.08 to -8.58 × 10-3 (µg/mL)/(mg/day), p < 0.001, MD = -7.16 (µg/mL)/(mg/day), 95%CI = -9.96 to -4.36, p < 0.001, and MD = -4.87 (µg/mL)/(mg/day), 95%CI = -9.39 to -0.35, p = 0.035, respectively), but not for oxcarbazepine (MD = 1.16 × 10-3 (µg/mL)/(mg/day), 95%CI = -2.55 to 0.24 × 10-3, p = 0.10). The quality of studies was acceptable with an average rating score of 11.5. CONCLUSIONS: Data for lamotrigine, oxcarbazepine (and monohydroxycarbazepine) and levetiracetam demonstrate major changes in pharmacokinetics during pregnancy, suggesting the importance of therapeutic drug monitoring to assist clinicians in optimizing treatment outcomes.


Asunto(s)
Anticonvulsivantes , Complicaciones del Embarazo , Femenino , Humanos , Embarazo , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/sangre , Epilepsia/tratamiento farmacológico , Epilepsia/sangre , Lamotrigina/farmacocinética , Lamotrigina/sangre , Levetiracetam/farmacocinética , Oxcarbazepina/farmacocinética , Complicaciones del Embarazo/tratamiento farmacológico
3.
Ther Drug Monit ; 46(4): 548-551, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38531811

RESUMEN

ABSTRACT: This study evaluated perampanel pharmacokinetics and cytochrome P450 3A4 (CYP3A4) activity, assessed using the level of 4ß-hydroxycholesterol (4ß-OHC) as an endogenous biomarker of CYP3A4, before, during, and after pregnancy in a woman with epilepsy and compared these measurements with those from a control group of nonpregnant women with epilepsy. A 21-year-old pregnant woman was being treated with perampanel (serum concentration: 1120 ng/mL), lacosamide, and lamotrigine. After the first trimester, the lamotrigine concentration decreased markedly; however, the perampanel concentration remained almost unchanged (range, 1130-1320 ng/mL). Similarly, serum 4ß-OHC levels did not change during pregnancy (before pregnancy, 78.2 ng/mL; during pregnancy, 62.2-83.2 ng/mL). To compare these measurements with those in nonpregnant women, we enrolled 27 nonpregnant women with epilepsy (age range, 16-40 years). In the control patients, we found a strong negative correlation between the concentration-to-dose ratio of perampanel and the 4ß-OHC level ( r = -0.78, P < 0.001). As there was no significant change in CYP3A4 activity, we concluded that the serum perampanel concentration did not change significantly before, during, or after pregnancy. More patients need to be studied to confirm these early results.


Asunto(s)
Anticonvulsivantes , Citocromo P-450 CYP3A , Epilepsia , Nitrilos , Piridonas , Humanos , Femenino , Piridonas/farmacocinética , Piridonas/sangre , Piridonas/uso terapéutico , Embarazo , Citocromo P-450 CYP3A/metabolismo , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapéutico , Anticonvulsivantes/sangre , Nitrilos/farmacocinética , Adulto , Adulto Joven , Epilepsia/tratamiento farmacológico , Adolescente , Lamotrigina/farmacocinética , Lamotrigina/uso terapéutico , Lamotrigina/sangre , Complicaciones del Embarazo/tratamiento farmacológico , Lacosamida/farmacocinética , Lacosamida/uso terapéutico , Hidroxicolesteroles
4.
Eur J Clin Pharmacol ; 80(6): 839-845, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38396309

RESUMEN

PURPOSE: Lamotrigine was previously reported to reduce serum concentration of quetiapine. The aim of this study was to investigate whether lamotrigine dose or quetiapine formulation was of importance for the drug interaction. METHODS: Patients combining lamotrigine with quetiapine (cases) were included retrospectively from a routine therapeutic drug monitoring (TDM) service, as were a control group of patients using quetiapine without any interacting drugs. The case and control groups were divided into groups using immediate release (IR) and extended release (XR) quetiapine. The case group was further split into high-dose (> 200 mg/day) and low-dose (≤ 200 mg/day) lamotrigine users. Quetiapine concentration-to-dose (C/D) ratio and metabolite-to-parent ratio (MPR) were compared between the control group and dose-separated case groups using ANOVA test and t-tests. RESULTS: In total, 406 patients were included. The mean C/D ratio of IR quetiapine was 46% lower in the high-dose lamotrigine group compared with the control group (P < 0.001), while no interaction effect was present in the low dose lamotrigine group (P = 0.7). Regardless of lamotrigine dose, there was no difference in quetiapine C/D ratio for patients using the XR formulation (P = 0.4). The quetiapine MPR was unaffected regardless of formulation and lamotrigine dose (P ≥ 0.06). CONCLUSION: The effect of lamotrigine in reducing quetiapine concentration is only significant for patients using quetiapine IR tablets who are treated with lamotrigine doses > 200 mg/day. Because of high variability in the interaction effect, TDM of quetiapine should be recommended during co-prescription of high-dose lamotrigine.


Asunto(s)
Antipsicóticos , Preparaciones de Acción Retardada , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Lamotrigina , Fumarato de Quetiapina , Comprimidos , Humanos , Lamotrigina/farmacocinética , Lamotrigina/administración & dosificación , Lamotrigina/sangre , Lamotrigina/uso terapéutico , Fumarato de Quetiapina/farmacocinética , Fumarato de Quetiapina/administración & dosificación , Fumarato de Quetiapina/sangre , Masculino , Femenino , Antipsicóticos/administración & dosificación , Antipsicóticos/farmacocinética , Antipsicóticos/sangre , Persona de Mediana Edad , Adulto , Estudios Retrospectivos , Monitoreo de Drogas/métodos , Triazinas/farmacocinética , Triazinas/sangre , Triazinas/administración & dosificación , Anciano
5.
Breastfeed Med ; 17(4): 341-348, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35049332

RESUMEN

Importance: Lamotrigine use during breastfeeding has significantly increased in the recent years, whereas breast milk lamotrigine pharmacokinetics data are still sparse. Objectives: To assess lamotrigine exposure in breastfed infants by monitoring maternal serum and breast milk concentrations. Methods: Breastfeeding women treated with lamotrigine were recruited to this study. Maternal trough breast milk and serum samples were collected, and additional breast milk samples were collected 1, 3, 6, 9, 12 hours after lamotrigine consumption. Trough breast milk/serum ratios (M/S ratio) and breast milk area under the curve (AUC) values were calculated. Results: Twenty-one breastfeeding women were recruited to this study, and the final dataset was based on the samples collected from 17 women. Lamotrigine trough serum and mother's milk concentrations were 5.1 ± 3.3 mg/L and 3.1 ± 1.9 mg/L, respectively (mean ± standard deviation). The trough M/S ratio of lamotrigine was 0.66 ± 0.22. The lamotrigine breast milk average AUC was 41.7 ± 24.6 mg·h/L. The estimated infant dose of lamotrigine was 0.52 ± 0.31 mg/kg/day and 0.26 ± 0.15 mg/kg/day for fully and partially breastfed infants, respectively. Significant correlation was found between the maternal lamotrigine serum trough concentrations and the breast milk parameters: trough breast milk concentrations (Spearman's rho = 0.986, p < 0.0001) and breast milk AUC values (Spearman's rho = 0.941, p < 0.0001). No significant correlation was found between the maternal lamotrigine daily dose and serum trough concentrations, breast milk trough concentrations, and breast milk AUC values (Spearman's rho = 0.294, 0.285, and 0.438, p = 0.252, 0.396, and 0.078, respectively). Conclusion and Relevance: High correlation between the maternal lamotrigine trough serum concentrations and the breast milk AUC values was found, implying that monitoring the maternal lamotrigine serum concentrations can be useful for prediction of exposure of infants to lamotrigine through the breast milk. The trial was registered in the Israeli trials registry MOH_2021-09-05_010243 at September 5, 2021 Retrospectively registered https://my.health.gov.il/CliniTrials.


Asunto(s)
Lactancia Materna , Leche Humana , Anticonvulsivantes/farmacocinética , Femenino , Humanos , Lactante , Lamotrigina/farmacocinética
6.
Pak J Pharm Sci ; 34(3): 875-882, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34602409

RESUMEN

For many patients with refractory epilepsy, antiepileptic drugs (AEDs) cannot reach effective therapeutic concentration in brain due to drugtolerance. In order to increase the selectivity of lamotrigine in brain, lamotrigine loaded nano-liposomes (LTG-NL) were designed, prepared, and the physio-chemical characterizations were observed. The distribution of LTG-NL in mice was studied by detecting the concentration of LTG extracted from animal organs, then targeting efficiency (TE) and targeting index (TI) were calculated to evaluate the brain targeting effect of LTG-NL. The mechanism of LTG-NL entry into cell was determined by A549 cell internalization experiments. The results showed that LTG-NL were small and uniform spherical particles with high entrapment efficiency and release. In vivo distribution study showed brain selectivity of LTG-NL, and TE and TI values further demonstrated the targeting capacity of LTG-NL. The cell internalization of LTG-NL was mainly by the pathway of clathrin-mediated endocytosis and macropinocytosis. These findings suggested this lipid formulation would be a drug delivery system for insoluble drugs to promote drug release and enhance brain selectivity.


Asunto(s)
Anticonvulsivantes/farmacocinética , Encéfalo/metabolismo , Lamotrigina/farmacocinética , Liposomas , Nanoestructuras , Células A549 , Animales , Anticonvulsivantes/administración & dosificación , Sistemas de Liberación de Medicamentos , Epilepsia/tratamiento farmacológico , Humanos , Lamotrigina/administración & dosificación , Ratones
7.
AAPS J ; 23(4): 70, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-34002327

RESUMEN

Current methods to assess risk in infants exposed to maternal medication through breast milk do not specifically account for infants most vulnerable to high drug exposure. A workflow applied to lamotrigine incorporated variability in infant anatomy and physiology, milk intake volume, and milk concentration to predict infant exposure. An adult physiologically based pharmacokinetic model of lamotrigine was developed and evaluated. The model was scaled to account for growth and maturation of a virtual infant population (n=100). Daily infant doses were simulated using milk intake volume and concentration models described by a nonlinear equation of weight-normalized intake across infant age and a linear function on the relationship of observed milk concentrations and maternal doses, respectively. Average infant plasma concentration at steady state was obtained through simulation. Models were evaluated by comparing observed to simulated infant plasma concentrations from breastfeeding infants based on a 90% prediction interval (PI). Upper AUC ratio (UAR) was defined as a novel risk metric. Twenty-five paired (milk concentrations measured) and 18 unpaired (milk concentrations unknown) infant plasma samples were retrieved from the literature. Forty-four percent and 11% of the paired and unpaired infant plasma concentrations were outside of the 90% PI, respectively. Over all ages (0-7 months), unpaired predictions captured more observed infant plasma concentrations within 90% PI than paired. UAR was 0.18-0.44 when mothers received 200 mg lamotrigine, suggesting that infants can receive 18-44% of the exposure per dose as compared to adults. UARs determined for further medications could reveal trends to better classify at-risk mother-infant pairs.


Asunto(s)
Anticonvulsivantes/farmacocinética , Lactancia Materna/efectos adversos , Lamotrigina/farmacocinética , Leche Humana/química , Administración Oral , Adulto , Factores de Edad , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/efectos adversos , Área Bajo la Curva , Femenino , Humanos , Lactante , Recién Nacido , Lamotrigina/administración & dosificación , Lamotrigina/efectos adversos , Modelos Biológicos , Distribución Tisular
8.
Ther Drug Monit ; 43(3): 394-400, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33851939

RESUMEN

BACKGROUND: Drug concentrations of antiepileptic drugs (AEDs) are routinely determined from blood serum or plasma at trough levels (before intake of morning dose). In capillary blood collection, blood is taken from the fingertip with the aid of a disposable tool and dried on absorbent material. The volumetric absorptive microsampling technique offers several advantages over the use of filter paper cards. The aim of this study was to determine conversion factors for the estimation of AED serum concentrations from capillary blood concentrations. METHODS: Venous and capillary blood samples were collected from adult inpatients with epilepsy who were treated with lacosamide (LCM, n = 30), lamotrigine (LTG, n = 40), and/or levetiracetam (LEV, n = 36). A validated liquid chromatography-mass spectrometry (LC-MS) method for dried blood samples for these AEDs was compared with routine serum laboratory methods. Method agreement was evaluated using different regression techniques, and the conversion factors were calculated. RESULTS: Regression analyses revealed a linear relationship between serum and capillary blood concentrations for all 3 AEDs (r ≥ 0.95). For LTG, the regression intercept was significantly different from 0, indicating that the relationship was linear, but not necessarily proportional. Although LEV and LCM concentrations tended to be lower in capillary blood than in serum (mean ratio of serum concentration to capillary blood concentration: 1.14 and 1.22, respectively), LTG concentrations were higher in capillary blood (mean ratio = 0.85). CONCLUSIONS: The estimation of serum concentrations from measured capillary blood concentrations is feasible for LCM, LTG, and LEV. A simple ratio approach using the mean ratio and Passing-Bablok regression showed the best results for all 3 AEDs. The volumetric absorptive microsampling technique facilitates the quantitative sample collection of capillary blood and overcomes the drawbacks associated with the classical dried blood spot technique.


Asunto(s)
Anticonvulsivantes/farmacocinética , Monitoreo de Drogas , Lacosamida/farmacocinética , Lamotrigina/farmacocinética , Levetiracetam/farmacocinética , Adulto , Anticonvulsivantes/sangre , Pruebas con Sangre Seca , Humanos , Lacosamida/sangre , Lamotrigina/sangre , Levetiracetam/sangre , Valores de Referencia , Suero
9.
Pharmacol Res ; 169: 105610, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33857625

RESUMEN

During pregnancy, various physiological changes occur that can alter the pharmacokinetics of antiepileptic drugs, such as lamotrigine (LTG). Anticipating the change in LTG dose required to achieve a pre-pregnancy target concentration is challenging. This study aimed to develop a refined population pharmacokinetic (PopPK) model of LTG in pregnant women with epilepsy (WWE) to identify factors explaining the variability in pharmacokinetics and to establish a model-informed individualized dosing regimen. On that basis, a coarsened model containing only clinical variables was also developed to examine its predictive performance compared to the refined model. In total, 322 concentration-time points from 51 pregnant WWE treated with LTG were employed to establish a refined PopPK model that included endogenous estrogen profiles, variants of candidate genes encoding LTG-metabolizing enzymes and -transporter proteins, and other clinical variables and a coarsened model that included only clinical variables, respectively. Data from an additional 11 patients were used for external validation of these two models. A nonlinear mixed-effect modeling approach was used for PopPK analysis of LTG. The standard goodness-of-fit method, bootstrap, normalized prediction distribution errors and external evaluation were adopted to estimate the stability and predictive performance of the candidate models. Akaike information criterion (AIC) was used to compare the goodness of fit between these two models. A lower AIC indicates a better fit of the data and the preferred model. Recommended dosing regimens for pregnant WWE were selected using Monte Carlo simulation based on the established optimal model. In the refined PopPK model, the population mean of apparent LTG clearance (CL/F) in pregnant WWE was estimated to be 2.82 L/h, with an inter-individual variability of 23.6%. PopPK analysis indicated that changes in estrogen profile during pregnancy were the predominant reason for the significant variations in LTG-CL/F. Up to the 3rd trimester, the concentration accumulation effect of E2 increased LTG-CL/F by 5.109 L/h from baseline levels. Contrary to effect of E2, E3 as the main circulating estrogen in pregnancy with a peak value of 34.41 ng/mL is 1000-fold higher than that in non-pregnancy reduced LTG-CL/F by 1.413 L/h. In addition, the UGT2B7 rs4356975 C > T and ABCB1 rs1128503 A > G variants may contribute to a better understanding of the inter-individual variability in LTG-CL/F. LTG-CL/F was 1.66-fold higher in UGT2B7 rs4356975 CT or TT genotype carriers than in CC genotype carriers. In contrast, ABCB1 rs1128503 GG genotype carriers had only 71.9% of the LTG-CL/F of AA or AG genotype carriers. In the coarsened PopPK model, the gestational age was a promising predictor of changes in LTG-CL/F. When comparing these two models, the refined PopPK model was favored over the coarsened PopPK model (AIC = -30.899 vs. -20.017). Monte Carlo simulation based on optimal PopPK model revealed that the LTG dosage administered to carriers of the UGT2B7 rs4356975 CT or TT genotype required a 33-50% increase to reach the pre-pregnancy target concentration, and carriers of the ABCB1 rs1128503 GG genotype required a 33-66% lower dose of LTG than carriers of the ABCB1 rs1128503 AA or AG genotype. Changes in estrogen profile during pregnancy was a better predictor of variations in LTG-CL/F than gestational age. The developed model based on estrogen profile and pharmacogenetics can serve as a foundation for further optimization of dosing regimens of LTG in pregnant WWE.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Epilepsia/complicaciones , Estrógenos/sangre , Lamotrigina/administración & dosificación , Complicaciones del Embarazo/tratamiento farmacológico , Adulto , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapéutico , Cálculo de Dosificación de Drogas , Vías de Eliminación de Fármacos/genética , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Lamotrigina/farmacocinética , Lamotrigina/uso terapéutico , Polimorfismo de Nucleótido Simple/genética , Embarazo , Complicaciones del Embarazo/sangre
10.
Sci Rep ; 11(1): 5568, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692435

RESUMEN

The pharmacokinetic variability of lamotrigine (LTG) plays a significant role in its dosing requirements. Our goal here was to use noninvasive clinical parameters to predict the dose-adjusted concentrations (C/D ratio) of LTG based on machine learning (ML) algorithms. A total of 1141 therapeutic drug-monitoring measurements were used, 80% of which were randomly selected as the "derivation cohort" to develop the prediction algorithm, and the remaining 20% constituted the "validation cohort" to test the finally selected model. Fifteen ML models were optimized and evaluated by tenfold cross-validation on the "derivation cohort," and were filtered by the mean absolute error (MAE). On the whole, the nonlinear models outperformed the linear models. The extra-trees' regression algorithm delivered good performance, and was chosen to establish the predictive model. The important features were then analyzed and parameters of the model adjusted to develop the best prediction model, which accurately described the C/D ratio of LTG, especially in the intermediate-to-high range (≥ 22.1 µg mL-1 g-1 day), as illustrated by a minimal bias (mean relative error (%) = + 3%), good precision (MAE = 8.7 µg mL-1 g-1 day), and a high percentage of predictions within ± 20% of the empirical values (60.47%). This is the first study, to the best of our knowledge, to use ML algorithms to predict the C/D ratio of LTG. The results here can help clinicians adjust doses of LTG administered to patients to minimize adverse reactions.


Asunto(s)
Monitoreo de Drogas , Lamotrigina , Aprendizaje Automático , Modelos Biológicos , Femenino , Humanos , Lamotrigina/administración & dosificación , Lamotrigina/farmacocinética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
11.
Epilepsia ; 62(2): 285-302, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33426641

RESUMEN

The safety of switching between generic products of antiseizure medications (ASMs) continues to be a hot topic in epilepsy management. The main reason for concern relates to the uncertainty on whether, and when, two generics found to be bioequivalent to the same brand (reference) product are bioequivalent to each other, and the risk of a switch between generics resulting in clinically significant changes in plasma ASM concentrations. This article addresses these concerns by discussing the distinction between bioequivalence and statistical testing for significant difference, the importance of intra-subject variability in interpreting bioequivalence studies, the stricter regulatory bioequivalence requirements applicable to narrow-therapeutic-index (NTI) drugs, and the extent by which currently available generic products of ASMs comply with such criteria. Data for 117 oral generic products of second-generation ASMs approved in Europe by the centralized, mutual recognition or decentralized procedure were analyzed based on a review of publicly accessible regulatory assessment reports. The analysis showed that for 99% of generic products assessed (after exclusion of gabapentin products), the 90% confidence intervals (90% CIs) of geometric mean ratios (test/reference) for AUC (area under the drug concentration vs time curve) were narrow and wholly contained within the acceptance interval (90%-111%) applied to NTI drugs. Intra-subject variability for AUC was <10% for 53 (88%) of the 60 products for which this measure was reported. Many gabapentin generics showed broader, 90% CIs for bioequivalence estimates, and greater intra-subject variability, compared with generics of other ASMs. When interpreted within the context of other available data, these results suggest that any risk of non-bioequivalence between these individual generic products is small, and that switches across these products are not likely to result in clinically relevant changes in plasma drug exposure. The potential for variability in exposure when switching across generics is likely to be greatest for gabapentin.


Asunto(s)
Anticonvulsivantes/farmacocinética , Equivalencia Terapéutica , Área Bajo la Curva , Variación Biológica Individual , Dibenzazepinas/farmacocinética , Sustitución de Medicamentos , Medicamentos Genéricos , Europa (Continente) , Gabapentina/farmacocinética , Humanos , Lacosamida/farmacocinética , Lamotrigina/farmacocinética , Levetiracetam/farmacocinética , Oxcarbazepina/farmacocinética , Pregabalina/farmacocinética , Topiramato/farmacocinética , Vigabatrin/farmacocinética , Zonisamida/farmacocinética
12.
J Clin Pharmacol ; 61(5): 677-687, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33244764

RESUMEN

Lamotrigine is a broad-spectrum antiepileptic drug with high interindividual variability in serum concentrations in children. The aims of this study were to evaluate the predictive performance of pediatric population pharmacokinetic (PPK) models published on lamotrigine, to build a new model with our monitoring data and to evaluate the current recommended doses. A validation cohort included patients treated with lamotrigine who had a serum level assayed during therapeutic drug monitoring (TDM). PPK models published in the literature were first applied to the validation cohort. We assessed their predictive performance using mean prediction errors, root mean squared errors, and visual predictive checks. A new model was then built using the data. Dose simulations were performed to evaluate the doses recommended. We included 270 lamotrigine concentrations ranging from 0.5 to 17.9 mg/L from 175 patients. The median (range) age and weight were 11.8 years (0.8-18 years) and 32.7 kg (8-110 kg). We tested 6 PPK models; most had acceptable bias and precision but underestimated the variability of the cohort. We built a 1-compartment model with first-order absorption and elimination, allometric scaling, and effects of inhibitor and inducer comedications. In our cohort, 22.6% of trough concentrations were below 2.5 mg/L. In conclusion, we proposed a PPK model that can be used for TDM of lamotrigine in children. In our population, a high percentage of children had low trough concentrations of lamotrigine. As the intervals of recommended doses are large, we suggest aiming at the higher range of doses to reach the target concentration.


Asunto(s)
Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Lamotrigina/farmacocinética , Lamotrigina/uso terapéutico , Adolescente , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/efectos adversos , Peso Corporal , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Monitoreo de Drogas , Femenino , Humanos , Lactante , Lamotrigina/administración & dosificación , Lamotrigina/efectos adversos , Masculino , Tasa de Depuración Metabólica , Modelos Biológicos
13.
Seizure ; 82: 133-147, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33060011

RESUMEN

BACKGROUND: Lamotrigine (LTG) is a new generation antiepileptic drug. However, relatively high interindividual pharmacokinetic variability of this drug has been documented. Therefore, several population pharmacokinetic studies of lamotrigine were conducted to identify factors influencing its pharmacokinetics. OBJECTIVE: This systematic review aimed to summarize significant factors influencing LTG pharmacokinetics and their relationships with pharmacokinetic parameters as well as the magnitude of pharmacokinetic variability. METHODS: Four databases i.e. PubMed, Scopus, CINAHL Complete, and Science Direct were systematically searched from their inception to March 2020. Population pharmacokinetic studies of LTG conducted in humans using a nonlinear-mixed effect approach were eligible for a systematic review. RESULTS: Nineteen studies were included in this systematic review. Most studies characterized LTG pharmacokinetics as a one-compartment model structure. The three most frequently identified significant covariates influencing LTG clearance included concomitant antiepileptic drugs, body weight, and genetic polymorphisms. Approximately 58% of the studies did not externally validate the models. CONCLUSIONS: For clinical application, LTG maintenance dose could be optimized using population pharmacokinetic models employing covariates such as concomitant antiepileptic drugs, body weight, and genetic polymorphisms. However, these models should be assessed for their predictability in the target population before utilizing such models in clinical settings.


Asunto(s)
Anticonvulsivantes , Lamotrigina , Triazinas , Anticonvulsivantes/farmacocinética , Peso Corporal , Humanos , Lamotrigina/farmacocinética
14.
Drug Des Devel Ther ; 14: 4343-4362, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33116420

RESUMEN

PURPOSE: This study aimed to prepare solid self-nanoemulsified drug delivery system (S-SNEDDS) of lamotrigine (LMG) for enhancing its dissolution and oral bioavailability (BA). METHODS: Nineteen liquid SNEDDS were prepared (R1-R19) using D-optimal design with different ratios of oil, surfactant (S), and cosurfactant (Cos). The formulations were characterized regarding robustness to dilution, droplet size, thermodynamic stability testing, self-emulsification time, in-vitro release in 0.1 N HCl and phosphate buffer (PB; pH 6.8). Design Expert® 11 software was used to select the optimum formulations. Eight S-SNEDDS were prepared (S1-S8) using 23 factorial design, and characterized by differential scanning calorimetry (DSC), powder x-ray diffraction (PXRD), and scanning electron microscopy (SEM). The optimum formulation was chosen regarding in-vitro drug released in 0.1 N HCl and PB, compared to pure LMG and commercial tablet (Lamictal®). The BA of LMG from the optimized S-SNEDDS formulation was evaluated in rabbits compared to pure LMG and Lamictal®. RESULTS: The optimized S-SNEDDS was S2, consisting of R9 adsorbed on Aeroperl® 300 in a ratio of 1:1, with the best results regarding in-vitro drug released in 0.1 N HCl at 15 min (100%) compared to pure LMG (73.40%) and Lamictal® (79.43%), and in-vitro drug released in PB at 45 min (100%) compared to pure LMG (30.46%) and Lamictal® (92.08%). DSC, PXRD, and SEM indicated that LMG was molecularly dispersed within the solid nano-system. The BA of S2 was increased 2.03 and 1.605 folds compared to pure LMG, and Lamictal®, respectively. CONCLUSION: S2 is a promising S-SNEDDS formulation. It can be a potential carrier for improving dissolution, and BA of LMG.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/farmacocinética , Lamotrigina/administración & dosificación , Lamotrigina/farmacocinética , Animales , Disponibilidad Biológica , Rastreo Diferencial de Calorimetría , Cristalografía por Rayos X , Portadores de Fármacos , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Diseño de Fármacos , Estabilidad de Medicamentos , Emulsiones , Conejos , Programas Informáticos , Solubilidad , Comprimidos , Termodinámica
16.
Semin Perinatol ; 44(3): 151224, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32199600

RESUMEN

OBJECTIVE: Breastmilk is recommended as the exclusive source of nutrition for infants younger than 6 months due to the numerous health benefits for both infants and mothers. Although many women are prescribed medications during pregnancy and postpartum, limited data are available to assist women in weighing the benefits compared to the risks of peripartum medication use. The goals of this paper are to discuss the importance of breastmilk for the health of both the mother and infant, evaluate the impact of medication use on women's infant feeding choice, describe the transfer of drugs to breastmilk and infants, and provide a framework for clinicians to support evidence-based counseling for women treated for mood disorders. RECOMMENDATIONS: We recommend early pregnancy counseling to discuss the benefits and risks of medications during breastfeeding. The Surgeon General's Call to Action (2011) highlights the short and long-term negative health effects of not providing breastmilk. Integrating recommendations from the pediatric and obstetric teams allows patients to make decisions based on evidence and reach their infant feeding goals. Databases containing summaries of research findings and pharmacologic properties of the drug of interest are an essential resource for clinicians.


Asunto(s)
Antidepresivos/farmacocinética , Antimaníacos/farmacocinética , Trastorno Bipolar/tratamiento farmacológico , Toma de Decisiones , Trastorno Depresivo/tratamiento farmacológico , Lactancia/metabolismo , Leche Humana/química , Antidepresivos/efectos adversos , Antidepresivos/metabolismo , Antimaníacos/efectos adversos , Antimaníacos/metabolismo , Antipsicóticos/efectos adversos , Antipsicóticos/metabolismo , Antipsicóticos/farmacocinética , Femenino , Humanos , Lamotrigina/efectos adversos , Lamotrigina/metabolismo , Lamotrigina/farmacocinética , Compuestos de Litio/efectos adversos , Compuestos de Litio/metabolismo , Compuestos de Litio/farmacocinética , Participación del Paciente
17.
Molecules ; 25(5)2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32120992

RESUMEN

Nasal drug delivery has become a popular research field in the last years. This is not surprising since the nose possesses unique anatomical and physical properties. Via the nasal mucosa local, systemic, and directly central nerve systemic (CNS) effect is achievable. Powders have favorable physicochemical properties over liquid formulations. Lamotrigine (LAM) is an antiepileptic agent with a relatively mild side effect spectrum, but only available in tablet form on market. Reducing the particle size to the nano range can affect the bioavailability of pharmaceutical products. The aim of this article was to continue the work started, compare the in vitro properties of a nanonized lamotrigine containing nasal powder (nanoLAMpowder) and its physical mixture (PM) that were prepared by dry milling. Moreover, to study their trans-epithelial absorption to reach the blood and target the brain by axonal transport. Due to the dry milling technique, the particle size of LAM, their surface and also their structure changed that led to higher in vitro dissolution and permeability rate. The results of the in vivo tests showed that the axonal transport of the drug was assumable by both intranasal formulations because the drug was present in the brain within a really short time, but the LAM from the nanoLAMpowder liberated even faster.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Química Farmacéutica/métodos , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/métodos , Lamotrigina/administración & dosificación , Nanopartículas/administración & dosificación , Polvos/administración & dosificación , Administración Intranasal , Animales , Anticonvulsivantes/sangre , Anticonvulsivantes/farmacocinética , Transporte Axonal , Disponibilidad Biológica , Rastreo Diferencial de Calorimetría , Cromatografía Liquida , Lamotrigina/sangre , Lamotrigina/farmacocinética , Masculino , Espectrometría de Masas , Microscopía Electrónica de Rastreo , Nanopartículas/química , Nanopartículas/ultraestructura , Cavidad Nasal , Mucosa Nasal/efectos de los fármacos , Mucosa Nasal/metabolismo , Tamaño de la Partícula , Permeabilidad , Ratas , Ratas Sprague-Dawley , Solubilidad
19.
Semin Perinatol ; 44(3): 151230, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32151481

RESUMEN

Optimal dose management of psychotropic drugs during the perinatal period reduces the risk for recurrence of mood episodes in women with Bipolar Disorder. Physiological changes during pregnancy are associated with decreases in the plasma concentrations of the majority of mood stabilizing medications. Regular symptom and drug concentration monitoring for lithium and anticonvulsants with reflexive dose adjustment improves the probability of sustained symptom remission across pregnancy. The elimination clearance trajectory across pregnancy for psychotropics dictates the frequency of laboratory monitoring and dose adjustment. The literature on the pharmacokinetics of lithium, lamotrigine, carbamazepine and atypical antipsychotics during pregnancy and postpartum are reviewed, recommendations for symptom and laboratory monitoring are proposed and recommendations for dose adjustments are presented.


Asunto(s)
Antimaníacos/uso terapéutico , Antipsicóticos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Lactancia/metabolismo , Complicaciones del Embarazo/tratamiento farmacológico , Embarazo/metabolismo , Trastornos Puerperales/tratamiento farmacológico , Antimaníacos/metabolismo , Antimaníacos/farmacocinética , Antipsicóticos/metabolismo , Antipsicóticos/farmacocinética , Carbamazepina/metabolismo , Carbamazepina/farmacocinética , Carbamazepina/uso terapéutico , Vías de Eliminación de Fármacos , Femenino , Humanos , Lamotrigina/metabolismo , Lamotrigina/farmacocinética , Lamotrigina/uso terapéutico , Compuestos de Litio/metabolismo , Compuestos de Litio/farmacocinética , Compuestos de Litio/uso terapéutico , Atención Perinatal , Efectos Tardíos de la Exposición Prenatal
20.
Clin Pharmacol Ther ; 107(4): 934-943, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31957870

RESUMEN

Postmarketing population pharmacokinetic (PK) and pharmacodynamic (PD) studies can be useful to capture patient characteristics affecting PK or PD in real-world settings. These studies require longitudinally measured dose, outcomes, and covariates in large numbers of patients; however, prospective data collection is cost-prohibitive. Electronic health records (EHRs) can be an excellent source for such data, but there are challenges, including accurate ascertainment of drug dose. We developed a standardized system to prepare datasets from EHRs for population PK/PD studies. Our system handles a variety of tasks involving data extraction from clinical text using a natural language processing algorithm, data processing, and data building. Applying this system, we performed a fentanyl population PK analysis, resulting in comparable parameter estimates to a prior study. This new system makes the EHR data extraction and preparation process more efficient and accurate and provides a powerful tool to facilitate postmarketing population PK/PD studies using information available in EHRs.


Asunto(s)
Interpretación Estadística de Datos , Registros Electrónicos de Salud/estadística & datos numéricos , Fentanilo/farmacocinética , Lamotrigina/farmacocinética , Vigilancia de Productos Comercializados/estadística & datos numéricos , Tacrolimus/farmacocinética , Adolescente , Adulto , Anciano , Analgésicos Opioides/farmacocinética , Bases de Datos Factuales/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vigilancia de Productos Comercializados/métodos , Adulto Joven
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