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Maglalang PD, Wen J, Hornik CP, Gonzalez D. Sources of pharmacokinetic and pharmacodynamic variability and clinical pharmacology studies of antiseizure medications in the pediatric population. Clin Transl Sci 2024; 17:e13793. [PMID: 38618871 PMCID: PMC11017206 DOI: 10.1111/cts.13793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/08/2024] [Accepted: 03/25/2024] [Indexed: 04/16/2024] Open
Abstract
Multiple treatment options exist for children with epilepsy, including surgery, dietary therapies, neurostimulation, and antiseizure medications (ASMs). ASMs are the first line of therapy, and more than 30 ASMs have U.S. Food and Drug Administration (FDA) approval for the treatment of various epilepsy and seizure types in children. Given the extensive FDA approval of ASMs in children, it is crucial to consider how the physiological and developmental changes throughout childhood may impact drug disposition. Various sources of pharmacokinetic (PK) variability from different extrinsic and intrinsic factors such as patients' size, age, drug-drug interactions, and drug formulation could result in suboptimal dosing of ASMs. Barriers exist to conducting clinical pharmacological studies in neonates, infants, and children due to ethical and practical reasons, limiting available data to fully characterize these drugs' disposition and better elucidate sources of PK variability. Modeling and simulation offer ways to circumvent traditional and intensive clinical pharmacology methods to address gaps in epilepsy and seizure management in children. This review discusses various physiological and developmental changes that influence the PK and pharmacodynamic (PD) variability of ASMs in children, and several key ASMs will be discussed in detail. We will also review novel trial designs in younger pediatric populations, highlight the role of extrapolation of efficacy in epilepsy, and the use of physiologically based PK modeling as a tool to investigate sources of PK/PD variability in children. Finally, we will conclude with current challenges and future directions for optimizing the efficacy and safety of these drugs across the pediatric age spectrum.
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Affiliation(s)
- Patricia D. Maglalang
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of PharmacyThe University of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Jiali Wen
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of PharmacyThe University of North Carolina at Chapel HillChapel HillNorth CarolinaUSA
| | - Christoph P. Hornik
- Duke Clinical Research InstituteDurhamNorth CarolinaUSA
- Department of PediatricsDuke University School of MedicineDurhamNorth CarolinaUSA
| | - Daniel Gonzalez
- Duke Clinical Research InstituteDurhamNorth CarolinaUSA
- Division of Clinical Pharmacology, Department of MedicineDuke University School of MedicineDurhamNorth CarolinaUSA
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Wei S, Li X, Zhang Q, Wu H, Wu Y, Zhao Z, Mei S, Feng W. Population pharmacokinetics of topiramate in Chinese children with epilepsy. Eur J Clin Pharmacol 2023; 79:1401-1415. [PMID: 37597080 DOI: 10.1007/s00228-023-03549-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/05/2023] [Indexed: 08/21/2023]
Abstract
OBJECTIVE Topiramate, a broad-spectrum antiepileptic drug, exhibits substantial inter-individual variability in both its pharmacokinetics and therapeutic response. The aim of this study was to investigate the influence of patient characteristics and genetic variants on topiramate clearance using population pharmacokinetic (PPK) models in a cohort of Chinese pediatric patients with epilepsy. METHOD The PPK model was constructed using a nonlinear mixed-effects modeling approach, utilizing a dataset comprising 236 plasma concentrations of topiramate obtained from 181 pediatric patients with epilepsy. A one-compartment model combined with a proportional residual model was employed to characterize the pharmacokinetics of topiramate. Covariate analysis was performed using forward addition and backward elimination to assess the influence of covariates on the model parameters. The model was thoroughly evaluated through goodness-of-fit analysis, bootstrap, visual predictive checks, and normalized prediction distribution errors. Monte Carlo simulations were utilized to devise topiramate dosing strategies. RESULT In the final PPK models of topiramate, body weight, co-administration with oxcarbazepine, and a combined genotype of GKIR1-UGT (GRIK1 rs2832407, UGT2B7 rs7439366, and UGT1A1 rs4148324) were identified as significant covariates affecting the clearance (CL). The clearance was estimated using the formulas CL (L/h) = 0.44 × (BW⁄11.7)0.82 × eOXC for the model without genetic variants and CL (L/h) = 0.49 × (BW⁄11.7)0.81 × eOXC × eGRIK1-UGT for the model incorporating genetic variants. The volume of distribution (Vd) was estimated using the formulas Vd (L) = 6.6 × (BW⁄11.7). The precision of all estimated parameters was acceptable. Furthermore, the model demonstrated good predictability, exhibiting stability and effectiveness in describing the pharmacokinetics of topiramate. CONCLUSION The clearance of topiramate in pediatric patients with epilepsy may be subject to the influence of factors such as body weight, co-administration with oxcarbazepine, and genetic polymorphism. In this study, PPK models were developed to better understand and account for these factors, thereby improving the precision and individualization of topiramate therapy in children with epilepsy.
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Affiliation(s)
- Shifeng Wei
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 119 Nansihuan West Road, Fengtai District, Beijing, 100070, People's Republic of China
- Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University, Beijing, 100069, People's Republic of China
| | - Xingmeng Li
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, 56 Nanlishi Road, Xicheng District, Beijing, 100045, People's Republic of China
| | - Qiang Zhang
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 119 Nansihuan West Road, Fengtai District, Beijing, 100070, People's Republic of China
- Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University, Beijing, 100069, People's Republic of China
| | - Han Wu
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 119 Nansihuan West Road, Fengtai District, Beijing, 100070, People's Republic of China
- Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University, Beijing, 100069, People's Republic of China
| | - Yun Wu
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, 56 Nanlishi Road, Xicheng District, Beijing, 100045, People's Republic of China
| | - Zhigang Zhao
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 119 Nansihuan West Road, Fengtai District, Beijing, 100070, People's Republic of China.
- Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University, Beijing, 100069, People's Republic of China.
| | - Shenghui Mei
- Department of Pharmacy, Beijing Tiantan Hospital, Capital Medical University, 119 Nansihuan West Road, Fengtai District, Beijing, 100070, People's Republic of China.
- Department of Clinical Pharmacology, College of Pharmaceutical Sciences, Capital Medical University, Beijing, 100069, People's Republic of China.
| | - Weixing Feng
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, 56 Nanlishi Road, Xicheng District, Beijing, 100045, People's Republic of China.
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Growth-related effects of antiseizure medications are of concern in children with epilepsy. DRUGS & THERAPY PERSPECTIVES 2023. [DOI: 10.1007/s40267-023-00981-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Treadwell JR, Kessler SK, Wu M, Abend NS, Massey SL, Tsou AY. Pharmacologic and Dietary Treatments for Epilepsies in Children Aged 1-36 Months: A Systematic Review. Neurology 2023; 100:e16-e27. [PMID: 36270899 PMCID: PMC9827128 DOI: 10.1212/wnl.0000000000201026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 06/13/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Early life epilepsies are common and often debilitating, but no evidence-based management guidelines exist outside of those for infantile spasms. We conducted a systematic review of the effectiveness and harms of pharmacologic and dietary treatments for epilepsy in children aged 1-36 months without infantile spasms. METHODS We searched EMBASE, MEDLINE, PubMed, and the Cochrane Library for studies published from January 1, 1999, to August 19, 2021. Using prespecified criteria, we identified studies reporting data on children aged 1-36 months receiving pharmacologic or dietary treatments for epilepsy. We did not require that studies report etiology-specific data. We excluded studies of neonates, infantile spasms, and status epilepticus. We included studies administering 1 of 29 pharmacologic treatments and/or 1 of 5 dietary treatments reporting effectiveness outcomes at ≥ 12 weeks. We reviewed the full text to find any subgroup analyses of children aged 1-36 months. RESULTS Twenty-three studies met inclusion criteria (6 randomized studies, 2 nonrandomized comparative studies, and 15 prestudies/poststudies). All conclusions were rated low strength of evidence. Levetiracetam leads to seizure freedom in some infants (32% and 66% in studies reporting seizure freedom), but data on 6 other medications were insufficient to permit conclusions about effectiveness (topiramate, lamotrigine, phenytoin, vigabatrin, rufinamide, and stiripentol). Three medications (levetiracetam, topiramate, and lamotrigine) were rarely discontinued because of adverse effects, and severe events were rare. For diets, the ketogenic diet leads to seizure freedom in some infants (rates 12%-37%), and both the ketogenic diet and modified Atkins diet reduce average seizure frequency, but reductions are greater with the ketogenic diet (1 RCT reported a 71% frequency reduction at 6 months for ketogenic diet vs only a 28% reduction for the modified Atkins diet). Dietary harms were not well-reported. DISCUSSION Little high-quality evidence exists on pharmacologic and dietary treatments for early life epilepsies. Future research should isolate how treatments contribute to outcomes, conduct etiology-specific analyses, and report patient-centered outcomes such as hospitalization, neurodevelopment, functional performance, sleep quality, and patient and caregiver quality of life. TRIAL REGISTRATION INFORMATION This systematic review was registered in PROSPERO (CRD42021220352) on March 5, 2021.
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Affiliation(s)
- Jonathan R Treadwell
- From the ECRI-Penn Medicine Evidence-based Practice Center (J.R.T., M.W., A.Y.T.), ECRI, Plymouth Meeting, PA; Department of Pediatrics (Division of Neurology) (S.K.K., N.S.A., S.L.M.), Children's Hospital of Philadelphia; Departments of Neurology and Pediatrics (S.K.K., N.S.A., S.L.M.), University of Pennsylvania Perelman School of Medicine; Department of Anesthesia & Critical Care (N.S.A.), University of Pennsylvania Perelman School of Medicine; Department of Biostatistics, Epidemiology and Informatics (N.S.A.), University of Pennsylvania Perelman School of Medicine; and Division of Neurology (A.Y.T.), Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA.
| | - Sudha Kilaru Kessler
- From the ECRI-Penn Medicine Evidence-based Practice Center (J.R.T., M.W., A.Y.T.), ECRI, Plymouth Meeting, PA; Department of Pediatrics (Division of Neurology) (S.K.K., N.S.A., S.L.M.), Children's Hospital of Philadelphia; Departments of Neurology and Pediatrics (S.K.K., N.S.A., S.L.M.), University of Pennsylvania Perelman School of Medicine; Department of Anesthesia & Critical Care (N.S.A.), University of Pennsylvania Perelman School of Medicine; Department of Biostatistics, Epidemiology and Informatics (N.S.A.), University of Pennsylvania Perelman School of Medicine; and Division of Neurology (A.Y.T.), Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
| | - Mingche Wu
- From the ECRI-Penn Medicine Evidence-based Practice Center (J.R.T., M.W., A.Y.T.), ECRI, Plymouth Meeting, PA; Department of Pediatrics (Division of Neurology) (S.K.K., N.S.A., S.L.M.), Children's Hospital of Philadelphia; Departments of Neurology and Pediatrics (S.K.K., N.S.A., S.L.M.), University of Pennsylvania Perelman School of Medicine; Department of Anesthesia & Critical Care (N.S.A.), University of Pennsylvania Perelman School of Medicine; Department of Biostatistics, Epidemiology and Informatics (N.S.A.), University of Pennsylvania Perelman School of Medicine; and Division of Neurology (A.Y.T.), Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
| | - Nicholas S Abend
- From the ECRI-Penn Medicine Evidence-based Practice Center (J.R.T., M.W., A.Y.T.), ECRI, Plymouth Meeting, PA; Department of Pediatrics (Division of Neurology) (S.K.K., N.S.A., S.L.M.), Children's Hospital of Philadelphia; Departments of Neurology and Pediatrics (S.K.K., N.S.A., S.L.M.), University of Pennsylvania Perelman School of Medicine; Department of Anesthesia & Critical Care (N.S.A.), University of Pennsylvania Perelman School of Medicine; Department of Biostatistics, Epidemiology and Informatics (N.S.A.), University of Pennsylvania Perelman School of Medicine; and Division of Neurology (A.Y.T.), Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
| | - Shavonne L Massey
- From the ECRI-Penn Medicine Evidence-based Practice Center (J.R.T., M.W., A.Y.T.), ECRI, Plymouth Meeting, PA; Department of Pediatrics (Division of Neurology) (S.K.K., N.S.A., S.L.M.), Children's Hospital of Philadelphia; Departments of Neurology and Pediatrics (S.K.K., N.S.A., S.L.M.), University of Pennsylvania Perelman School of Medicine; Department of Anesthesia & Critical Care (N.S.A.), University of Pennsylvania Perelman School of Medicine; Department of Biostatistics, Epidemiology and Informatics (N.S.A.), University of Pennsylvania Perelman School of Medicine; and Division of Neurology (A.Y.T.), Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
| | - Amy Y Tsou
- From the ECRI-Penn Medicine Evidence-based Practice Center (J.R.T., M.W., A.Y.T.), ECRI, Plymouth Meeting, PA; Department of Pediatrics (Division of Neurology) (S.K.K., N.S.A., S.L.M.), Children's Hospital of Philadelphia; Departments of Neurology and Pediatrics (S.K.K., N.S.A., S.L.M.), University of Pennsylvania Perelman School of Medicine; Department of Anesthesia & Critical Care (N.S.A.), University of Pennsylvania Perelman School of Medicine; Department of Biostatistics, Epidemiology and Informatics (N.S.A.), University of Pennsylvania Perelman School of Medicine; and Division of Neurology (A.Y.T.), Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA
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Abstract
There are numerous potential factors that may affect growth in children with epilepsy, and these must be evaluated in any child with appetite and weight concerns. Antiseizure medications (ASMs) have potential adverse effects, and many may affect appetite, thus impacting normal growth and weight gain. The aim of this review is to focus on the impact of both epilepsy and ASMs on appetite and weight in children. We systematically reviewed studies using Medline assessing the impact of ASMs on appetite and weight in children. Eligible studies included randomized controlled trials and open-label studies (open-label extension and interventional) that targeted or included the pediatric population (0-18 years of age). Each study was classified using the American Academy of Neurology (AAN) Classification of Evidence for Therapeutic Studies, and the level of evidence for impact on appetite and weight in children was graded. ASMs associated with decreased appetite and/or weight loss include fenfluramine, topiramate, zonisamide, felbamate, rufinamide, stiripentol, cannabidiol, brivaracetam and ethosuximide; ASMs with minimal impact on weight and appetite in children include oxcarbazepine, eslicarbazepine, lamotrigine, levetiracetam, lacosamide, carbamazepine, vigabatrin and clobazam. The ASM most robustly associated with increased appetite and/or weight gain is valproic acid; however, both pregabalin and perampanel may also lead to modest weight gain or increased appetite in children. Certain ASMs may impact both appetite and weight, which may lead to increased morbidity of the underlying disease and impaired adherence to the treatment regimen.
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Vawter-Lee M, Natarajan N, Rang K, Horn PS, Pardo AC, Thomas CW. Topiramate Is Safe for Refractory Neonatal Seizures: A Multicenter Retrospective Cohort Study of Necrotizing Enterocolitis Risk. Pediatr Neurol 2022; 129:7-13. [PMID: 35131568 DOI: 10.1016/j.pediatrneurol.2021.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/30/2021] [Accepted: 12/06/2021] [Indexed: 11/17/2022]
Abstract
BACKGROUND A previously published, single-institution, case series suggested an association between topiramate administration in neonates and subsequent development of necrotizing enterocolitis (NEC). This contradicted our more extensive experiences using topiramate in this population. We therefore studied safety and tolerability of topiramate for treating refractory neonatal seizures, hypothesizing that the risk of developing NEC following topiramate exposure was low and that most infants tolerate topiramate. METHODS This multicenter retrospective cohort study included seventy-five neonates who received topiramate to treat seizures from January 2011 to October 2019 at three geographically diverse level IV neonatal intensive care units affiliated with pediatric tertiary hospitals. Data included demographics, birth history, seizure etiology, treatment response, side effects, and occurrence and details of NEC. RESULTS Three of seventy-five infants (4%) developed NEC following topiramate exposure. These infants did not differ in gestational age, birth weight, seizure etiology, postmenstrual age, weight when topiramate was initiated, or dosing of topiramate. Topiramate was well tolerated. Only three infants (4%) discontinued due to side effects. The most common side effect (20%) was weight loss (typically <5%). Topiramate was felt to be efficacious (61%). Most infants (72%) continued topiramate when discharged. CONCLUSIONS Our multicenter, 75-infant study demonstrated that development of NEC after treatment with topiramate was rare (4%) and refutes prior literature suggesting an association. Topiramate was felt to be efficacious and was well tolerated. Although limited by retrospective design, study data are broadly applicable and support thoughtful use of topiramate as a safe, reasonable option for treating refractory neonatal seizures.
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Affiliation(s)
- Marissa Vawter-Lee
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio; Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Niranjana Natarajan
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington; Division of Pediatric Neurology, Department of Neurology, University of Washington, Seattle, Washington
| | - Kelly Rang
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio; Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Paul S Horn
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio; Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Andrea C Pardo
- Division of Pediatric Neurology, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois; Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Cameron W Thomas
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio; Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
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Influence of Topiramate on the Synaptic Endings of the Temporal Lobe Neocortex in an Experimental Model of Hyperthermia-Induced Seizures: An Ultrastructural Study. Brain Sci 2021; 11:brainsci11111433. [PMID: 34827435 PMCID: PMC8615765 DOI: 10.3390/brainsci11111433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 11/17/2022] Open
Abstract
The objective of this pioneering study was to assess potentially neuroprotective properties of topiramate (TPM), a broad spectrum and newer-generation antiepileptic used against damage to synaptic endings of the temporal lobe neocortex in experimental hyperthermia-induced seizures (HS). TPM (80 mg/kg b.m.) was administered in young male Wistar rats with an intragastric tube before and immediately after HS. Specimens (1 mm3) collected from the neocortex, fixed via transcardial perfusion with paraformaldehyde and glutaraldehyde solution, were routinely processed for transmission-electron microscopic study, i.e., for descriptive and morphometric analysis. The ultrastructure of neocortical neuropil components affected by hyperthermic stress showed distinct swelling of pre and post-synaptic axodendritic and axospinal endings, including total disintegration. Mitochondria were markedly damaged in synaptic structures. Axoplasm of presynaptic boutons contained a decreased number of synaptic vesicles. Synaptic junctions showed active zone-shortening. Preventive administration of TPM before HS induction demonstrated neuroprotective effects against synaptic damage in approximately 1/4 of these structures. Interestingly, beneficial effects on synapsis morphology were more common in perivascular zones close to well-preserved capillaries. They were demonstrated by smaller swelling of both presynaptic and postsynaptic parts, well-preserved mitochondria, an increased number and regular distribution of synaptic vesicles within axoplasm, and a significantly increased synaptic active zones. However, topiramate used directly after HS was ineffective in the prevention of hyperthermia-evoked synaptic injury. Our findings support the hypothesis that topiramate applied before HS can protect some neocortical synapses via the vascular factor by enhancing blood-brain barrier components and improving the blood supply of gray matter in the temporal lobe, which may be significant in febrile seizure-prevention in children.
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Monitoring topiramate concentrations at delivery and during lactation. Biomed Pharmacother 2021; 138:111446. [PMID: 33676308 DOI: 10.1016/j.biopha.2021.111446] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE To determine transplacental passage of topiramate and its transport to colostrum, mature maternal milk and breastfed infants, we examined data from 27 women treated with topiramate from 2004 to 2020. METHODS In this cohort study, maternal serum, umbilical cord serum, milk and infant serum levels were measured by gas chromatography in the delivery subgroup, the colostrum subgroup (3-4 days postpartum) and the mature milk subgroup (7-30 days postpartum). Paired umbilical cord serum, maternal serum, breastfed infant serum, and milk levels were used to assess the ratios of umbilical cord/maternal serum, milk/maternal serum and infant/maternal serum levels. RESULTS Topiramate levels varied from 1.0 to 7.1 mg/L in maternal serum and from 0.8 to 6.2 mg/L in umbilical cord serum, and the mean umbilical cord/maternal serum ratio was 0.93 ± 0.11. At 3-4 days after delivery, topiramate concentrations were 1.4-8.4 mg/L in maternal serum, 1.5-8.6 mg/L in milk and 0.3-4.4 mg/L in infant serum. The mean milk/maternal serum ratio was 0.99 ± 0.45, and the mean infant/maternal serum ratio was 0.25 ± 0.15. At 7-30 days after delivery, maternal serum levels varied from 1.9 to 9.7 mg/L, milk levels ranged from 2.3 to 10.6 mg/L and infant serum levels ranged from 0.3 to 6.5 mg/L. The mean milk/maternal serum ratio was 1.07 ± 0.31, and the mean infant/maternal serum ratio was 0.51 ± 0.27. CONCLUSIONS We extended information about free transplacental passage of topiramate and its extensive transport to maternal milk with lower serum concentrations in breastfed infants in the largest group of patients ever reported to our knowledge. DATA AVAILABILITY STATEMENT Authors declare that take full responsibility for the data, the analyses and interpretation, and the conduct of the research; that they have full access to all of the data; and that they have the right to publish all data. Authors were not participations in industry-sponsored research and corporate activities for evaluation of a manuscript.
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Marques MR, Garcia‐Robles A, Usach I, Vento M, Poveda JL, Peris JE, Mangas‐Sanjuan V. Topiramate pharmacokinetics in neonates undergoing therapeutic hypothermia and proposal of an optimised dosing schedule. Acta Paediatr 2020; 109:300-308. [PMID: 31336401 DOI: 10.1111/apa.14944] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/09/2019] [Accepted: 07/18/2019] [Indexed: 11/28/2022]
Abstract
AIM The adequate dosing of topiramate in neonates undergoing therapeutic hypothermia has not been established. The aim of this study was to design a dosing schedule capable of providing topiramate serum concentrations within the accepted therapeutic range. METHODS Neonates (n = 52) with hypoxic ischaemic encephalopathy and subjected to therapeutic hypothermia were dosed with topiramate, 5 mg/kg on day one and 3 mg/kg on days two to five, to decrease seizure events. A total of 451 topiramate serum concentrations obtained in the patients were used to develop a population pharmacokinetic model using a non-linear mixed-effects modelling approach. RESULTS A one-compartment model with first-order absorption and two different clearance terms, one for the cooling period and another for the post-warming period, were used to describe the concentration-time topiramate data. The probability of no-seizure events could not be related to topiramate concentrations, which was attributed to excessively low topiramate concentrations. A modified dosage schedule was designed with the aim of obtaining more than 90% of patients with topiramate concentrations within the therapeutic range after the first dose. CONCLUSION The dosage schedule of topiramate in these patients should be modified with the aim of decreasing the frequency of seizure events.
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Affiliation(s)
- María Remedios Marques
- Department of Pharmacy Services University and Polytechnic Hospital La Fe Valencia Spain
| | - Ana Garcia‐Robles
- Division of Neonatology University and Polytechnic Hospital La Fe Valencia Spain
| | - Iris Usach
- Department of Pharmacy and Pharmaceutical Technology and Parasitology University of Valencia Valencia Spain
| | - Maximo Vento
- Division of Neonatology University and Polytechnic Hospital La Fe Valencia Spain
| | - José Luis Poveda
- Department of Pharmacy Services University and Polytechnic Hospital La Fe Valencia Spain
| | - José Esteban Peris
- Department of Pharmacy and Pharmaceutical Technology and Parasitology University of Valencia Valencia Spain
| | - Victor Mangas‐Sanjuan
- Department of Pharmacy and Pharmaceutical Technology and Parasitology University of Valencia Valencia Spain
- Interuniversity Research Institute for Molecular Recognition and Technological Development Polytechnic University of Valencia‐University of Valencia Valencia Spain
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News of the Academy of Neonatal Nursing. Neonatal Netw 2019; 37:186-192. [PMID: 29789061 DOI: 10.1891/0730-0832.37.3.186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Moavero R, Pisani LR, Pisani F, Curatolo P. Safety and tolerability profile of new antiepileptic drug treatment in children with epilepsy. Expert Opin Drug Saf 2018; 17:1015-1028. [PMID: 30169997 DOI: 10.1080/14740338.2018.1518427] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
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.
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Affiliation(s)
- Romina Moavero
- a Child Neurology and Psychiatry Unit, Systems Medicine Department , Tor Vergata University of Rome , Rome , Italy.,b Child Neurology Unit, Neuroscience and Neurorehabilitation Department , "Bambino Gesù", Children's Hospital, IRCCS , Rome , Italy
| | | | - Francesco Pisani
- d Department of Clinical and Experimental Medicine , University of Messina , Messina , Italy
| | - Paolo Curatolo
- a Child Neurology and Psychiatry Unit, Systems Medicine Department , Tor Vergata University of Rome , Rome , Italy
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Yozawitz E, Stacey A, Pressler RM. Pharmacotherapy for Seizures in Neonates with Hypoxic Ischemic Encephalopathy. Paediatr Drugs 2017; 19:553-567. [PMID: 28770451 DOI: 10.1007/s40272-017-0250-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Seizures are common in neonates with moderate and severe hypoxic ischemic encephalopathy (HIE) and are associated with worse outcomes, independent of HIE severity. In contrast to adults and older children, no new drugs have been licensed for treatment of neonatal seizures over the last 50 years, because of a lack of controlled clinical trials. Hence, many antiseizure medications licensed in older children and adults are used off-label for neonatal seizure, which is associated with potential risks of adverse effects during a period when the brain is particularly vulnerable. Phenobarbital is worldwide the first-line drug and is considered standard of care, although there is a limited evidence base for its efficacy. Second-line agents include phenytoin, benzodiazepines, levetiracetam, and lidocaine. These drugs are discussed in more detail along with two emerging drugs (bumetanide and topiramate). More safety, pharmacokinetic, and efficacy data are needed from well-designed clinical trials to develop safe and effective antiseizure regimes for the treatment of neonatal seizures in HIE.
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Affiliation(s)
- Elissa Yozawitz
- Department of Neurology and Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Arthur Stacey
- UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Ronit M Pressler
- Department of Clinical Neurophysiology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, Great Ormond Street, London, WC1N 3JH, UK. .,Clinical Neurosciences, UCL- Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.
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Yamamoto Y, Takahashi Y, Imai K, Kagawa Y, Inoue Y. Effect of CYP Inducers/Inhibitors on Topiramate Concentration: Clinical Value of Therapeutic Drug Monitoring. Ther Drug Monit 2017; 39:55-61. [PMID: 27941476 DOI: 10.1097/ftd.0000000000000367] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND This study investigated the pharmacokinetic interactions between topiramate (TPM) and concomitant antiepileptic drugs and evaluated the therapeutic concentration range of TPM and the effect of the achieved plasma concentration on the retention rate of TPM therapy. METHODS A total of 1217 plasma samples obtained from 610 patients were retrospectively investigated, and the concentration-to-dose ratio (CD ratio) of TPM was compared among patients on various antiepileptic drug regimens. In addition, the therapeutic concentration of TPM was reviewed in patients on long-term therapy, and factors influencing the retention rate of TPM were analyzed by the Kaplan-Meier method. RESULTS Among patients using hepatic enzyme inducers (phenytoin, phenobarbital, and carbamazepine), the CD ratio was reduced by 45.4% in adults and 33.3% in children. Patients taking phenytoin concomitantly had a significantly lower CD ratio than patients taking phenobarbital or carbamazepine. Among noninducers, concomitant use of stiripentol increased the CD ratio. In 276 patients who remained on TPM therapy for more than 2 years, the mean therapeutic concentration was 5.1 mcg/mL (15.0 μmol/L). The estimated retention day was significantly higher for patients with a TPM concentration >5 mcg/mL than that for patients with a concentration <5 mcg/mL (945 versus 802 days; P = 0.007 by the log-rank test). Also, patients without hepatic enzyme inducers had a significantly higher retention rate than patients using such inducers (P = 0.002). CONCLUSIONS Concomitant use of hepatic enzyme inducers markedly reduced the plasma TPM concentration and can decrease its antiepileptic effect. A therapeutic concentration of >5 mcg/mL TPM was significantly associated with continuation of therapy, and therapeutic drug monitoring can be helpful.
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Affiliation(s)
- Yoshiaki Yamamoto
- *Department of Clinical Research, NHO, National Epilepsy Center, Shizuoka Institute of Epilepsy and Neurological Disorders; †Department of Clinical Pharmaceutics, Graduate School of Pharmaceutical Sciences, University of Shizuoka; and ‡Laboratory of Clinical Pharmacokinetics and Drug Safety, Shizuoka General Hospital, Shizuoka, Japan
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Filippi L, Fiorini P, Catarzi S, Berti E, Padrini L, Landucci E, Donzelli G, Bartalena L, Fiorentini E, Boldrini A, Giampietri M, Scaramuzzo RT, la Marca G, Della Bona ML, Fiori S, Tinelli F, Bancale A, Guzzetta A, Cioni G, Pisano T, Falchi M, Guerrini R. Safety and efficacy of topiramate in neonates with hypoxic ischemic encephalopathy treated with hypothermia (NeoNATI): a feasibility study. J Matern Fetal Neonatal Med 2017; 31:973-980. [PMID: 28274169 DOI: 10.1080/14767058.2017.1304536] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE To investigate the feasibility of a study based on treatment with topiramate (TPM) added to moderate hypothermia in newborns with hypoxic ischemic encephalopathy (HIE). MATERIALS AND METHODS Multicenter randomized controlled trial. Term newborns with precocious metabolic, clinical and electroencephalographic (EEG) signs of HIE were selected according to their amplified integrated EEG pattern and randomized to receive either TPM (10 mg/kg once a day for the first three days of life) plus moderate hypothermia or hypothermia alone. Safety was assessed by monitoring cardiorespiratory parameters and blood samples collected to check renal, liver, metabolic balance and TPM pharmacokinetics. Efficacy was evaluated by the combined frequency of mortality and severe neurological disability as primary outcome. Incidence of magnetic resonance injury, epilepsy, blindness, hearing loss, neurodevelopment at 18-24 months of life was assessed as secondary outcomes. RESULTS Forty-four asphyxiated newborns were enrolled in the study. Twenty one newborns (10 with moderate and 11 with severe HIE) were allocated to hypothermia plus TPM and 23 (12 moderate and 11 severe HIE) to hypothermia. No statistically or clinically significant differences were observed for safety, primary or secondary outcomes. However, a reduction in the prevalence of epilepsy was observed in newborns co-treated with TPM. CONCLUSIONS Results of this pilot trial suggest that administration of TPM in newborns with HIE is safe but does not reduce the combined frequency of mortality and severe neurological disability. The role of TPM co-treatment in preventing subsequent epilepsy deserves further studies.
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Affiliation(s)
- Luca Filippi
- a Neonatal Intensive Care Unit, Medical Surgical Feto-Neonatal Department , "A. Meyer" University Children's Hospital , Florence , Italy
| | - Patrizio Fiorini
- a Neonatal Intensive Care Unit, Medical Surgical Feto-Neonatal Department , "A. Meyer" University Children's Hospital , Florence , Italy
| | - Serena Catarzi
- a Neonatal Intensive Care Unit, Medical Surgical Feto-Neonatal Department , "A. Meyer" University Children's Hospital , Florence , Italy
| | - Elettra Berti
- a Neonatal Intensive Care Unit, Medical Surgical Feto-Neonatal Department , "A. Meyer" University Children's Hospital , Florence , Italy
| | - Letizia Padrini
- a Neonatal Intensive Care Unit, Medical Surgical Feto-Neonatal Department , "A. Meyer" University Children's Hospital , Florence , Italy
| | - Elisa Landucci
- b Department of Health Sciences, Section of Clinical Pharmacology and Oncology , University of Florence , Florence , Italy
| | | | - Laura Bartalena
- d Neonatal Unit, Department of Clinical and Experimental Medicine , University of Pisa , Pisa , Italy
| | - Erika Fiorentini
- d Neonatal Unit, Department of Clinical and Experimental Medicine , University of Pisa , Pisa , Italy
| | - Antonio Boldrini
- d Neonatal Unit, Department of Clinical and Experimental Medicine , University of Pisa , Pisa , Italy
| | - Matteo Giampietri
- d Neonatal Unit, Department of Clinical and Experimental Medicine , University of Pisa , Pisa , Italy
| | - Rosa Teresa Scaramuzzo
- d Neonatal Unit, Department of Clinical and Experimental Medicine , University of Pisa , Pisa , Italy
| | - Giancarlo la Marca
- e Laboratory for Diseases of the Nervous System and Metabolism , "A. Meyer" University Children's Hospital , Florence , Italy
| | - Maria Luisa Della Bona
- e Laboratory for Diseases of the Nervous System and Metabolism , "A. Meyer" University Children's Hospital , Florence , Italy
| | - Simona Fiori
- f Department of Developmental Neuroscience , Stella Maris Scientific Institute , Pisa , Italy
| | - Francesca Tinelli
- f Department of Developmental Neuroscience , Stella Maris Scientific Institute , Pisa , Italy
| | - Ada Bancale
- f Department of Developmental Neuroscience , Stella Maris Scientific Institute , Pisa , Italy
| | - Andrea Guzzetta
- f Department of Developmental Neuroscience , Stella Maris Scientific Institute , Pisa , Italy
| | - Giovanni Cioni
- f Department of Developmental Neuroscience , Stella Maris Scientific Institute , Pisa , Italy
| | - Tiziana Pisano
- g Pediatric Neurology Unit and Laboratories , "A. Meyer" Children's Hospital, University of Florence , Florence , Italy
| | - Melania Falchi
- g Pediatric Neurology Unit and Laboratories , "A. Meyer" Children's Hospital, University of Florence , Florence , Italy
| | - Renzo Guerrini
- g Pediatric Neurology Unit and Laboratories , "A. Meyer" Children's Hospital, University of Florence , Florence , Italy
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Guo W, Shang DM, Cao JH, Feng K, He YC, Jiang Y, Wang S, Gao YF. Identifying and Analyzing Novel Epilepsy-Related Genes Using Random Walk with Restart Algorithm. BIOMED RESEARCH INTERNATIONAL 2017; 2017:6132436. [PMID: 28255556 PMCID: PMC5309434 DOI: 10.1155/2017/6132436] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Accepted: 01/15/2017] [Indexed: 02/07/2023]
Abstract
As a pathological condition, epilepsy is caused by abnormal neuronal discharge in brain which will temporarily disrupt the cerebral functions. Epilepsy is a chronic disease which occurs in all ages and would seriously affect patients' personal lives. Thus, it is highly required to develop effective medicines or instruments to treat the disease. Identifying epilepsy-related genes is essential in order to understand and treat the disease because the corresponding proteins encoded by the epilepsy-related genes are candidates of the potential drug targets. In this study, a pioneering computational workflow was proposed to predict novel epilepsy-related genes using the random walk with restart (RWR) algorithm. As reported in the literature RWR algorithm often produces a number of false positive genes, and in this study a permutation test and functional association tests were implemented to filter the genes identified by RWR algorithm, which greatly reduce the number of suspected genes and result in only thirty-three novel epilepsy genes. Finally, these novel genes were analyzed based upon some recently published literatures. Our findings implicate that all novel genes were closely related to epilepsy. It is believed that the proposed workflow can also be applied to identify genes related to other diseases and deepen our understanding of the mechanisms of these diseases.
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Affiliation(s)
- Wei Guo
- Department of Outpatient, China-Japan Union Hospital of Jilin University, Changchun 130033, China
| | - Dong-Mei Shang
- Department of Outpatient, China-Japan Union Hospital of Jilin University, Changchun 130033, China
| | - Jing-Hui Cao
- Department of Neurosurgery, China-Japan Union Hospital of Jilin University, Changchun 130033, China
| | - Kaiyan Feng
- Department of Computer Science, Guangdong AIB Polytechnic, Guangzhou 510507, China
| | - Yi-Chun He
- Department of Neurosurgery, China-Japan Union Hospital of Jilin University, Changchun 130033, China
| | - Yang Jiang
- Department of Surgery, China-Japan Union Hospital of Jilin University, Changchun 130033, China
| | - ShaoPeng Wang
- School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Yu-Fei Gao
- Department of Neurosurgery, China-Japan Union Hospital of Jilin University, Changchun 130033, China
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Abstract
USL255 is a once-daily, extended-release formulation of the well-established antiepileptic drug topiramate that was recently approved by the US FDA. As a capsule formulation, USL255 can be swallowed intact or opened and sprinkled onto soft food for patients with swallowing difficulties, including children (≥2 years old) and older patients. USL255 has been evaluated in seven key Phase I and III studies. Compared with immediate-release topiramate taken twice daily, once-daily USL255 provides equivalent topiramate exposure with a 26% reduction in plasma fluctuations. A multinational, Phase III, randomized, double-blind, placebo-controlled clinical trial in patients with refractory partial-onset seizures (PREVAIL) demonstrated that USL255 (200 mg/day) significantly improved seizure control and clinical outcomes versus placebo. USL255 is generally safe and well-tolerated, with a low incidence of neuropsychiatric and neurocognitive adverse events. These data suggest that USL255 may provide a useful treatment option for seizure control with convenient once-daily dosing.
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Affiliation(s)
- Steve Chung
- Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, 500 W. Thomas Road, Suite 300, Phoenix, AZ 85013, USA
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Gonzalez D, Paul IM, Benjamin DK, Cohen-Wolkowiez M. Advances in pediatric pharmacology, therapeutics, and toxicology. Adv Pediatr 2014; 61:7-31. [PMID: 25037123 PMCID: PMC4120955 DOI: 10.1016/j.yapd.2014.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In the United States, passage of the FDASIA legislation made BPCA and PREA permanent, no longer requiring reauthorization every 5 years. This landmark legislation also stressed the importance of performing clinical trials in neonates when appropriate. In Europe the Pediatric Regulation, which went into effect in early 2007, also provides a framework for expanding pediatric clinical research. Although much work remains, as a result of greater regulatory guidance more pediatric data are reaching product labels.
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Affiliation(s)
- Daniel Gonzalez
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, 301 Pharmacy Lane, Chapel Hill, NC 27599, USA; Duke Clinical Research Institute, Duke University Medical Center, 2400 Pratt Street, Durham, NC 27705, USA
| | - Ian M Paul
- Department of Pediatrics, College of Medicine, Penn State University, 500 University Drive, HS83, Hershey, PA 17033, USA; Department of Public Health Sciences, College of Medicine, Penn State University, 500 University Drive, HS83, Hershey, PA 17033, USA
| | - Daniel K Benjamin
- Duke Clinical Research Institute, Duke University Medical Center, 2400 Pratt Street, Durham, NC 27705, USA; Department of Pediatrics, College of Medicine, Duke University, T901/Children's Health Center, Durham, NC 27705, USA
| | - Michael Cohen-Wolkowiez
- Duke Clinical Research Institute, Duke University Medical Center, 2400 Pratt Street, Durham, NC 27705, USA; Department of Pediatrics, College of Medicine, Duke University, T901/Children's Health Center, Durham, NC 27705, USA.
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Italiano D, Perucca E. Clinical pharmacokinetics of new-generation antiepileptic drugs at the extremes of age: an update. Clin Pharmacokinet 2014; 52:627-45. [PMID: 23640503 DOI: 10.1007/s40262-013-0067-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Epilepsies occur across the entire age range, and their incidence peaks in the first years of life and in the elderly. Therefore, antiepileptic drugs (AEDs) are commonly used at the extremes of age. Rational prescribing in these age groups requires not only an understanding of the drugs' pharmacodynamic properties, but also careful consideration of potential age-related changes in their pharmacokinetic profile. The present article, which updates a review published in 2006 in this journal, focuses on recent findings on the pharmacokinetics of new-generation AEDs in neonates, infants, children, and the elderly. Significant new information on the pharmacokinetics of new AEDs in the perinatal period has been acquired, particularly for lamotrigine and levetiracetam. As a result of slow maturation of the enzymes involved in glucuronide conjugation, lamotrigine elimination occurs at a particularly slow rate in neonates, and becomes gradually more efficient during the first months of life. In the case of levetiracetam, elimination occurs primarily by renal excretion and is also slow at birth, but drug clearance increases rapidly thereafter and can even double within 1 week. In general, infants older than 2-3 months and children show higher drug clearance (normalized for body weight) than adults. This pattern was confirmed in recent studies that investigated the pediatric pharmacokinetics of several new AEDs, including levetiracetam, rufinamide, stiripentol, and eslicarbazepine acetate. At the other extreme of age, in the elderly, drug clearance is generally reduced compared with younger adults because of less efficient drug-metabolizing activity, decreased renal function, or both. This general pattern, described previously for several AEDs, was confirmed in recent studies on the effect of old age on the clearance of felbamate, levetiracetam, pregabalin, lacosamide, and retigabine. For those drugs which are predominantly eliminated by renal excretion, aging-related pharmacokinetic changes could be predicted by measuring creatinine clearance (CLCR). Overall, most recent findings confirm that age is a major factor influencing the pharmacokinetic profile of AEDs. However, pharmacokinetic variability at any age can be considerable, and the importance of other factors should not be disregarded. These include genetic factors, co-morbidities, and drug interactions, particularly those caused by concomitantly administered AEDs which induce or inhibit drug-metabolizing enzymes.
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Affiliation(s)
- Domenico Italiano
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
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Abstract
The treatment of neonatal seizures has not changed significantly over the last 50 years despite advances in antiepileptic drug (AED) development for older children and adults. Recently new drugs have emerged some of which address age-specific challenges or mechanisms and will be discussed in this review. The loop diuretic bumetanide blocks the neuronal NKCC1 co-transporter and is thought specifically to supress seizures in the immature brain. Levetiracetam has been used in children and infants with good efficacy, an excellent safety profile, and near-ideal pharmacokinetic characteristics. Randomised controlled trials are now underway to test the efficacy of some newer AEDs for neonatal seizures. Topiramate has been shown to have neuroprotective properties in addition to its antiepileptic action and trials in babies with hypoxic-ischaemic encephalopathy are now planned. There is an urgent need to develop age-specific AEDs for preterm and term babies. These drugs must be evaluated with multicentre, collaborative trials using innovative methods and high ethical standards to overcome age-specific challenges with the ultimate aim of improving the outcome for neonates with seizures.
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