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Farhan M, Rani P, Moledina F, George T, Tummala HP, Mallayasamy S. Application of Physiologically Based Pharmacokinetic Modeling of Lamotrigine Using PK-Sim in Predicting the Impact of Drug Interactions and Dosage Adjustment. J Pharmacol Pharmacother 2022. [DOI: 10.1177/0976500x221111455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background Physiologically based pharmacokinetic (PBPK) models are helpful as mechanistic representations of pharmacokinetic parameters. There were no reports of lamotrigine (LTG) PBPK models developed in open source platforms like PK-Sim. Objectives The present work was aimed to build a LTG PBPK model and compare it to the clinical data from South Asian Indian patients and use this model to understand the drug interactions of LTG and explore the optimal doses. Methods and Material The PBPK model was developed using the PK-Sim software platform and qualified with LTG plasma concentration data from an Indian study. The European population database was chosen as the patient setting in the software. Physicochemical data of LTG and enzyme kinetic data were incorporated from the literature. Dosing protocols were as per the previous study. Interaction models for drug interactions with carbamazepine and valproate were also simulated. Results Most of the model predicted concentration-time profiles of LTG at steady-state were well within the observed concentrations. The developed models were suitably qualified. The drug interaction model was used to assess the impact of induction and inhibition of the pharmacokinetic profile of LTG. Conclusions The predicted plasma concentrations of the developed PBPK models using the European population database were very similar to the data from Indian patients. The developed LTG PBPK models are applicable in predicting the impact of drug interactions and can yield appropriate LTG doses to be administered.
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Affiliation(s)
- Mohammed Farhan
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Prathvi Rani
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Fatimazahra Moledina
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Thomas George
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Hari Prabhath Tummala
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Surulivelrajan Mallayasamy
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal, Karnataka, India
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Dodin YI, Suyagh MF, Saleh MI, Nuseir ZT, Aburuz SM, Al-Qudah AA, Masri AT, Younes AM, Al-Ghazawi MA. Population Pharmacokinetics Modeling of Lamotrigine in Jordanian Epileptic Patients Using Dried Blood Spot Sampling. Drug Res (Stuttg) 2021; 71:429-437. [PMID: 34255318 DOI: 10.1055/a-1524-0913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AIMS To characterize the population pharmacokinetics of lamotrigine in Jordanian epileptic patients and to identify factors affecting therapeutic parameters. PATIENTS AND METHODS A population pharmacokinetics model for lamotrigine was established based on a prospectively collected data of 52 steady-state concentrations from 38 adult and pediatric patients with epilepsy. Lamotrigine concentrations were determined by a dried blood spot liquid chromatography method. Data were analyzed according to a one-compartment model with first-order absorption and elimination using the nonlinear mixed effect modeling program. The covariates effect of total body weight, gender, age, and co-medication with topiramate, carbamazepine, phenytoin, phenobarbital, and valproic acid on lamotrigine clearance were investigated using a stepwise forward addition followed by a stepwise backward elimination. RESULTS The final population pharmacokinetics model for lamotrigine clearance was as follows: CL/Fpop=θ1*exp (θ3*age)*exp (θ5*carbamazepine)*exp (θ6*valproic acid) , where θ1 is the relative clearance (L/hr) estimated, and θ3, θ5, and θ6 are the fixed parameters relating to age and co-medication with carbamazepine and valproic acid, respectively.The population mean value of lamotrigine total clearance generated in the final model (with covariates) was 2.12 L/hr. Inter-individual variability and residual unexplained variability expressed as the coefficient of variation was 37.1 and 26.1%, respectively. CONCLUSION Lamotrigine total clearance in the Jordanian patients is comparable to that reported by others for Caucasian patients. Age and concomitant therapy with carbamazepine and valproic acid significantly affected lamotrigine clearance, and accounted for 48% of its inter-individual variability.
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Affiliation(s)
- Yasmeen I Dodin
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, The University of Jordan, Amman, Jordan
| | - Maysa F Suyagh
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, The University of Jordan, Amman, Jordan
| | - Mohammad I Saleh
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, The University of Jordan, Amman, Jordan
| | - Ziad T Nuseir
- Division of Neurology, Department of Internal Medicine, Faculty of Medicine, The University of Jordan, Amman, Jordan
| | - Salah M Aburuz
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, The University of Jordan, Amman, Jordan
| | - Abdelkarim A Al-Qudah
- Division of Child Neurology, Department of Pediatrics, Faculty of Medicine, The University of Jordan, Amman, Jordan
| | - Amira T Masri
- Division of Child Neurology, Department of Pediatrics, Faculty of Medicine, The University of Jordan, Amman, Jordan
| | | | - Mutasim A Al-Ghazawi
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, The University of Jordan, Amman, Jordan
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Methaneethorn J, Leelakanok N. Sources of lamotrigine pharmacokinetic variability: A systematic review of population pharmacokinetic analyses. Seizure 2020; 82:133-147. [DOI: 10.1016/j.seizure.2020.07.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/10/2020] [Accepted: 07/19/2020] [Indexed: 12/14/2022] Open
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Chávez-Castillo CE, Medellín-Garibay SE, Milán-Segovia RDC, Rodríguez-Leyva I, Romano-Moreno S. Dosing Recommendations Based on Population Pharmacokinetics of Lamotrigine in Mexican Adult Patients With Epilepsy. J Pharm Sci 2020; 109:2902-2908. [DOI: 10.1016/j.xphs.2020.05.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/29/2020] [Accepted: 05/29/2020] [Indexed: 11/16/2022]
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van Dijkman SC, de Jager NCB, Rauwé WM, Danhof M, Della Pasqua O. Effect of Age-Related Factors on the Pharmacokinetics of Lamotrigine and Potential Implications for Maintenance Dose Optimisation in Future Clinical Trials. Clin Pharmacokinet 2019; 57:1039-1053. [PMID: 29363050 DOI: 10.1007/s40262-017-0614-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND AND AIMS In this study, we evaluate the performance of allometric concepts to predict the implications of age and size on the pharmacokinetics of lamotrigine, and assess the dose rationale across different age groups from 0.2 to 91 years. METHODS An allometrically scaled pharmacokinetic model was developed using adolescent and adult data, taking into account the effect of comedications. Model parameters were then used to extrapolate lamotrigine pharmacokinetics to older adults (> 65 years), children (4-12 years) and infants and toddlers (0.2-2.0 years). In addition, simulations were performed to identify the implication of different doses and dosing regimens for each population, so as to ensure steady-state concentrations within a predefined reference range. RESULTS The pharmacokinetics of lamotrigine was best described using a one-compartment model with first-order absorption and elimination. Carbamazepine, phenytoin, and valproic acid changed systemic clearance (CL) by + 76.5, + 129, and - 47.4%, respectively. Allometric principles allowed accurate extrapolation of disposition parameters to older adults and children older than 4 years of age. A maturation function was required to describe changes in exposure in younger patients. Compared with adults, a child aged 1.7 years has a 31.5% higher CL, after correcting for body weight. Patients > 65 years of age showed a decrease in CL of approximately 15%. CONCLUSION Population pharmacokinetic models are usually limited to a subgroup of patients, which may mask the identification of factors contributing to interindividual variability. The availability of an integrated model including the whole patient population provides insight into the role of age-related changes in the disposition of lamotrigine, and potential implications for maintenance dose optimisation in any future trials. TRIAL REGISTRATION According to GlaxoSmithKline's Clinical Trial Register, data from the GlaxoSmithKline studies LAM100034 and LEP103944, corresponding to ClinicalTrials.gov identifiers NCT00113165 and NCT00264615, used in this work, have been used in previous publications (doi: https://doi.org/10.1212/01.wnl.0000277698.33743.8b , https://doi.org/10.1111/j.1528-1167.2007.01274.x ).
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Affiliation(s)
- Sven C van Dijkman
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - Nico C B de Jager
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - Willem M Rauwé
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - Meindert Danhof
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - Oscar Della Pasqua
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Einsteinweg 55, 2333CC, Leiden, The Netherlands. .,Clinical Pharmacology Modelling and Simulation, GlaxoSmithKline, Uxbridge, UB11 1BT, UK. .,Clinical Pharmacology and Therapeutics Group, University College London, BMA House (North Entrance), Tavistock Square, London, WC1H 9JP, UK.
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Yu EQ, Jiao Z, Wang CY, Ding JJ, Zhang XH. Remedial dosing recommendations for delayed or missed doses of lamotrigine in pediatric patients with epilepsy using Monte Carlo simulations. Epilepsy Behav 2019; 96:132-140. [PMID: 31132614 DOI: 10.1016/j.yebeh.2019.04.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/03/2019] [Accepted: 04/07/2019] [Indexed: 11/18/2022]
Abstract
OBJECTIVE This study investigated the effect of delayed or missed doses on the pharmacokinetics (PK) of lamotrigine (LTG) in children with epilepsy and established remedial dosing recommendations for nonadherent patients. METHODS The Monte Carlo simulation based on a published LTG population PK model was used to assess the effect of different scenarios of nonadherence and the subsequently administered remedial regimens. The following three remedial approaches were investigated for each delayed dose: A) A partial dose was administered immediately, and the regular dose was administered at the next scheduled time. B) The delayed dose was administered immediately, followed by a partial dose at the next scheduled time. C) The delayed and partial doses were coadministered immediately, the next scheduled dose was skipped, and the regular dosing was resumed at the subsequent scheduled time. The most appropriate remedial regimen was that with the shortest deviation time from the individual therapeutic window. RESULTS The effect of nonadherence on PK was dependent on the delay duration and daily dose, and the recommended remedial dose was related to the delay duration and concomitant antiepileptic drugs. Remedial dosing strategies A and B were almost equivalent, whereas C showed a larger PK deviation time. If one dose was missed, double doses were not recommended for the next scheduled time. CONCLUSIONS Simulations provide quantitative insight into the remedial regimens for nonadherent patients, and clinicians should select the optimal regimen based on the status of patients.
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Affiliation(s)
- Er-Qian Yu
- The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Zheng Jiao
- Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai 200040, China.
| | - Chen-Yu Wang
- Department of Pharmacy, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Jun-Jie Ding
- Children's Hospital of Fudan University, Shanghai 201102, China
| | - Xiu-Hua Zhang
- The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China.
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Xu S, Liu L, Chen Y, Liu M, Lu T, Wang H, Liu S, Zhao M, Zhao L. Population pharmacokinetics of lamotrigine co-administered with valproic acid in Chinese epileptic children using nonlinear mixed effects modeling. Eur J Clin Pharmacol 2018; 74:583-591. [DOI: 10.1007/s00228-018-2414-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 01/04/2018] [Indexed: 11/28/2022]
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Population pharmacokinetic models of lamotrigine in different age groups of Chinese children with epilepsy. Eur J Clin Pharmacol 2017; 73:445-453. [PMID: 28064355 DOI: 10.1007/s00228-016-2190-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 12/26/2016] [Indexed: 10/20/2022]
Abstract
PURPOSE The study aims to establish population pharmacokinetic (PPK) models of lamotrigine (LTG) in different age groups of epileptic children by nonlinear mixed effect modelling(NONMEM), and provide essential tools and theoretical basis for individualised optimal drug dose. METHODS Cases of 473 epileptic children were divided into infant, toddler and preschool age (≤6 years) (n = 211), school age (6-12 years) (n = 171) and adolescence age (>12 years) (n = 81). A total of 625 steady-state serum trough concentration samples were extracted. The clinical information included demography, medication, serum concentration data and blood biochemical parameters. PPK models of LTG were established by NONMEM program, using first-order absorption and elimination. Demography and drug combination was investigated for influence on apparent clearance (CL) and apparent volume of distribution (Vd). To assess the accuracy and precision of the different ages and whole-age model, the mean prediction error (MPE), mean absolute error (MAE) and root mean squared error (RMSE) were compared. RESULTS The final model of LTG in different ages stage and whole age was as follows: (1) infant, toddler and preschool age CL = 0.715 × [(WEIG/16.25)0.655] × (0.458VPA) × (1.99IND), V = 10.4; (2) school age CL(L/h) = 1.01 × (WEIG/30)0.399 × 0.465VPA × 1.98IND, Vd(L) = 17.7; (3) adolescence age CL(L/h) = 1.49 × (WEIG/51.5)0.509 × 0.498VPA × 1.7IND, Vd(L) = 23.1; (4) whole age CL = 0.945 × [(WEIG/25)0.645] × (0.463VPA) × (1.94IND), V = 16.7 × (WEIG/25)0.919 (WEIG, total body weight; VPA, combination with valproate, yes = 1, no = 0; IND, combination with enzyme inducer, yes = 1, no = 0). The values of MPE, MAE and RMSE in age-stage-specific models were less than the ones in the whole-age model, which suggests the age-stage-specific models have better precision and accuracy than the whole-age model. CONCLUSION PPK models of LTG in different age groups of epileptic children were successfully established. Weight and combination therapy were identified as significant covariates on LTG clearance. Compared with the whole-age model, the age-specific models are more reliable.
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Milosheska D, Lorber B, Vovk T, Kastelic M, Dolžan V, Grabnar I. Pharmacokinetics of lamotrigine and its metabolite N-2-glucuronide: Influence of polymorphism of UDP-glucuronosyltransferases and drug transporters. Br J Clin Pharmacol 2016; 82:399-411. [PMID: 27096250 DOI: 10.1111/bcp.12984] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 03/31/2016] [Accepted: 04/18/2016] [Indexed: 01/16/2023] Open
Abstract
AIMS This study aimed to develop a population pharmacokinetic model for quantitative evaluation of the influence of genetic variants in metabolic enzymes and transporters on lamotrigine pharmacokinetics while taking into account the influence of various clinical, biochemical and demographic factors. METHODS We included 100 patients with epilepsy on stable dosing with lamotrigine as mono or adjunctive therapy. Lamotrigine and lamotrigine N-2-glucuronide concentrations were determined in up to two plasma samples per patient. Patients were genotyped for UGT1A4, UGT2B7, ABCB1 and SLC22A1. Population pharmacokinetic analysis was performed by non-linear mixed effects modelling. Prior knowledge from previous pharmacokinetic studies was incorporated to stabilize the modelling process. A parent-metabolite model was developed to get a more detailed view on the covariate effects on lamotrigine metabolism. RESULTS With a base model absorption rate (interindividual variability) was estimated at 1.96 h(-1) (72.8%), oral clearance at 2.32 l h(-1) (41.4%) and distribution volume at 77.6 l (30.2%). Lamotrigine clearance was associated with genetic factors, patient's weight, renal function, smoking and co-treatment with enzyme inducing or inhibiting drugs. In patients with UGT2B7-161TT genotype clearance was lower compared with GT and GG genotypes. Clearance was particularly high in patients with UGT2B7 372 GG genotype (compared with AA genotype it was 117%; 95% CI 44.8, 247% higher). CONCLUSIONS Variability in lamotrigine pharmacokinetics is large and quantification of its sources may lead to more precise individual treatment. Genotyping for UGT2B7 may be useful in various clinical settings.
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Affiliation(s)
| | - Bogdan Lorber
- Department of Neurology, University Medical Centre Ljubljana, 1000, Ljubljana
| | - Tomaž Vovk
- Faculty of Pharmacy, University of Ljubljana, 1000, Ljubljana
| | - Matej Kastelic
- Faculty of Medicine, Institute of Biochemistry, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Vita Dolžan
- Faculty of Medicine, Institute of Biochemistry, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Iztok Grabnar
- Faculty of Pharmacy, University of Ljubljana, 1000, Ljubljana
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Polepally AR, Pennell PB, Brundage RC, Stowe ZN, Newport DJ, Viguera AC, Ritchie JC, Birnbaum AK. MODEL-BASED LAMOTRIGINE CLEARANCE CHANGES DURING PREGNANCY: CLINICAL IMPLICATION. Ann Clin Transl Neurol 2014; 1:99-106. [PMID: 24883336 PMCID: PMC4038031 DOI: 10.1002/acn3.29] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Objective The objective of the study was to characterize changes in the oral clearance (CL/F) of lamotrigine (LTG) over the course of pregnancy and the postpartum period through a model-based approach incorporating clinical characteristics that may influence CL/F, in support of developing clinical management guidelines. Methods Women receiving LTG therapy who were pregnant or planning pregnancy were enrolled. Maternal blood samples were collected at each visit. A pharmacokinetic analysis was performed using a population-based, nonlinear, mixed-effects model. Results A total of 600 LTG concentrations from 60 women (64 pregnancies) were included. The baseline LTG CL/F was 2.16 L/h with a between-subject variability of 40.6%. The influence of pregnancy on CL/F was described by gestational week. Two subpopulations of women emerged based on the rate of increase in LTG CL/F during pregnancy. The gestational age-associated increase in CL/F displayed a 10-fold higher rate in 77% of the women (0.118 L/h per week) compared to 23% (0.0115 L/h per week). The between-subject variability in these slopes was 43.0%. The increased CL/F at delivery declined to baseline values with a half-life of 0.55 weeks. Interpretation The majority of women had a substantial increase in CL/F from 2.16 to 6.88 L/h by the end of pregnancy, whereas 23% of women had a minimal increase. An increase in CL/F may correspond to decreases in LTG blood concentrations necessitating the need for more frequent dosage adjustments and closer monitoring in some pregnant women with epilepsy. Postpartum doses should be tapered to preconception dose ranges within 3 weeks of delivery.
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Affiliation(s)
- Akshanth R Polepally
- Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota
| | - Page B Pennell
- Department of Neurology and Division of Women's Health at Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Richard C Brundage
- Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota
| | - Zachary N Stowe
- Department of Psychiatry, Pediatrics, and Obstetrics & Gynecology, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - D Jeffrey Newport
- Departments of Psychiatry and Obstetrics & Gynecology, The Ohio State University College of Medicine, Columbus, Ohio ; Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia
| | | | - James C Ritchie
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia ; Department of Pathology, Emory University School of Medicine
| | - Angela K Birnbaum
- Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota
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Brzaković B, Vučićević K, Kovačević SV, Miljković B, Prostran M, Martinović Ž, Pokrajac M. Pharmacokinetics of lamotrigine in paediatric and young adult epileptic patients--nonlinear mixed effects modelling approach. Eur J Clin Pharmacol 2013; 70:179-85. [PMID: 24240511 DOI: 10.1007/s00228-013-1606-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 10/23/2013] [Indexed: 11/28/2022]
Abstract
PURPOSE The purpose of the study was to examine and describe adjunctive lamotrigine (LTG) pharmacokinetics in paediatric and young adult patients using a nonlinear mixed effects modelling (NONMEM) approach. METHODS The study included 53 patients (age range 3-35 years) who were concomitantly treated with carbamazepine (CBZ) and/or valproic acid (VPA). A total of 70 blood samples corresponding to trough levels were available for analysis. Data were modelled, and the final model was evaluated using NONMEM and auxiliary software tools. RESULTS The final LTG population model included the effects of concomitant drugs and patient's weight (WT) which stratified the population into three groups: ≤25 kg, >25 to <60 kg and ≥60 kg. Based on the final model, the estimated LTG oral clearance (CL/F) for a typical patient weighing ≤25 kg, >25 to <60 kg or ≥60 kg who was concomitantly treated with CBZ was estimated to be 3.28, 4.23, or 7.15 l/h, respectively. If a patient was concomitantly treated with CBZ + VPA, the CL/F decreased on average by 69.5 % relative to LTG + CBZ co-therapy. VPA was found to decrease the LTG CL/F by 87.6 % compared to co-therapy with only CBZ. CONCLUSION The LTG population pharmacokinetic model developed in this study may be a reliable method for individualising the LTG dosing regimen in paediatric and young adult patients on combination therapy during therapeutic drug monitoring.
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Affiliation(s)
- Branka Brzaković
- Medicines and Medical Devices Agency of Serbia, Belgrade, Serbia
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