RESUMEN
This study investigated an association between the cytochrome P450 (CYP) 2C8*3 polymorphism with asthma symptom control in children and changes in lipid metabolism and pro-inflammatory signaling by human bronchial epithelial cells (HBECs) treated with cigarette smoke condensate (CSC). CYP genes are inherently variable in sequence, and while such variations are known to produce clinically relevant effects on drug pharmacokinetics and pharmacodynamics, the effects on endogenous substrate metabolism and associated physiologic processes are less understood. In this study, CYP2C8*3 was associated with improved asthma symptom control among children: Mean asthma control scores were 3.68 (n = 207) for patients with one or more copies of the CYP2C8*3 allele versus 4.42 (n = 965) for CYP2C8*1/*1 (P = 0.0133). In vitro, CYP2C8*3 was associated with an increase in montelukast 36-hydroxylation and a decrease in linoleic acid metabolism despite lower mRNA and protein expression. Additionally, CYP2C8*3 was associated with reduced mRNA expression of interleukin-6 (IL-6) and C-X-C motif chemokine ligand 8 (CXCL-8) by HBECs in response to CSC, which was replicated using the soluble epoxide hydrolase inhibitor, 12-[[(tricyclo[3.3.1.13,7]dec-1-ylamino)carbonyl]amino]-dodecanoic acid. Interestingly, 9(10)- and 12(13)- dihydroxyoctadecenoic acid, the hydrolyzed metabolites of 9(10)- and 12(13)- epoxyoctadecenoic acid, increased the expression of IL-6 and CXCL-8 mRNA by HBECs. This study reveals previously undocumented effects of the CYP2C8*3 variant on the response of HBECs to exogenous stimuli. SIGNIFICANCE STATEMENT: These findings suggest a role for CYP2C8 in regulating the epoxyoctadecenoic acid:dihydroxyoctadecenoic acid ratio leading to a change in cellular inflammatory responses elicited by environmental stimuli that exacerbate asthma.
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Asma , Bronquios , Citocromo P-450 CYP2C8 , Células Epiteliales , Humanos , Asma/tratamiento farmacológico , Asma/genética , Asma/metabolismo , Citocromo P-450 CYP2C8/genética , Citocromo P-450 CYP2C8/metabolismo , Niño , Masculino , Femenino , Bronquios/efectos de los fármacos , Bronquios/metabolismo , Bronquios/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Adolescente , Metabolismo de los Lípidos/efectos de los fármacos , Metabolismo de los Lípidos/genética , Inflamación/genética , Inflamación/metabolismo , Células Cultivadas , Quinolinas/farmacología , Polimorfismo de Nucleótido Simple , Acetatos , Ciclopropanos , SulfurosRESUMEN
OBJECTIVE: The current standard of care for Dravet syndrome (DS) includes polytherapy after inadequate seizure control with one or more monotherapy approaches. Treatment guidelines are often based on expert opinions, and finding an optimal balance between seizure control and adverse drug effects can be challenging. This study utilizes the efficacy and pharmacokinetic assessment of a second-line treatment regimen that combines clobazam and sodium valproate with an add-on drug as a proof-of-principle approach to establish an effective therapeutic regimen in a DS mouse model. METHODS: We evaluated the efficacy of add-on therapies stiripentol, cannabidiol, lorcaserin, or fenfluramine added to clobazam and sodium valproate against hyperthermia-induced seizures in Scn1aA1783V/WT mice. Clobazam, N-desmethyl clobazam (an active metabolite of clobazam), sodium valproate, stiripentol, and cannabidiol concentrations were quantified in plasma and brain using liquid chromatography-tandem mass spectrometry for the combinations deemed effective against hyperthermia-induced seizures. The concentration data were used to calculate pharmacokinetic parameters via noncompartmental analysis in Phoenix WinNonLin. RESULTS: Higher doses of stiripentol or cannabidiol, in combination with clobazam and sodium valproate, were effective against hyperthermia-induced seizures in Scn1aA1783V/WT mice. In Scn1aWT/WT mice, brain clobazam and N-desmethyl clobazam concentrations were higher in the triple-drug combinations than in the clobazam monotherapy. Stiripentol and cannabidiol brain concentrations were greater in the triple-drug therapy than when given alone. SIGNIFICANCE: A polypharmacy strategy may be a practical preclinical approach to identifying efficacious compounds for DS. The drug-drug interactions between compounds used in this study may explain the potentiated efficacy of some polytherapies.
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Genetic variation among inhaled corticosteroid (ICS)-metabolizing enzymes may affect asthma control, but evidence is limited. This study tested the hypothesis that single-nucleotide polymorphisms (SNPs) in Cytochrome P450 3A5 (CYP3A5) would affect asthma outcomes. Patients aged 2-18 years with persistent asthma were recruited to use the electronic AsthmaTracker (e-AT), a self-monitoring tool that records weekly asthma control, medication use, and asthma outcomes. A subset of patients provided saliva samples for SNP analysis and participated in a pharmacokinetic study. Multivariable regression analysis adjusted for age, sex, race, and ethnicity was used to evaluate the impact of CYP3A5 SNPs on asthma outcomes, including asthma control (measured using the asthma symptom tracker, a modified version of the asthma control test or ACT), exacerbations, and hospital admissions. Plasma corticosteroid and cortisol concentrations post-ICS dosing were also assayed using liquid chromatography-tandem mass spectrometry. Of the 751 patients using the e-AT, 166 (22.1%) provided saliva samples and 16 completed the PK study. The e-AT cohort was 65.1% male, and 89.6% White, 6.0% Native Hawaiian, 1.2% Black, 1.2% Native American, 1.8% of unknown race, and 15.7% Hispanic/Latino; the median age was 8.35 (IQR: 5.51-11.3) years. CYP3A5*3/*3 frequency was 75.8% in White subjects, 50% in Native Hawaiians and 76.9% in Hispanic/Latino subjects. Compared with CYP3A5*3/*3, the CYP3A5*1/*x genotype was associated with reduced weekly asthma control (OR: 0.98; 95% CI: 0.97-0.98; p < 0.001), increased exacerbations (OR: 6.43; 95% CI: 4.56-9.07; p < 0.001), and increased asthma hospitalizations (OR: 1.66; 95% CI: 1.43-1.93; p < 0.001); analysis of 3/*3, *1/*1 and *1/*3 separately showed an allelic copy effect. Finally, PK analysis post-ICS dosing suggested muted changes in cortisol concentrations for patients with the CYP3A5*3/*3 genotype, as opposed to an effect on ICS PK. Detection of CYP3A5*3/3, CYPA35*1/*3, and CYP3A5*1/*1 could impact inhaled steroid treatment strategies for asthma in the future.
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Corticoesteroides , Asma , Citocromo P-450 CYP3A , Polimorfismo de Nucleótido Simple , Humanos , Asma/tratamiento farmacológico , Asma/genética , Niño , Masculino , Femenino , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Adolescente , Preescolar , Corticoesteroides/uso terapéutico , Corticoesteroides/farmacocinética , Corticoesteroides/administración & dosificación , Genotipo , Hidrocortisona/sangre , Saliva/metabolismo , Resultado del TratamientoRESUMEN
OBJECTIVE: Pharmacokinetics (PK) of a drug drive its exposure, efficacy, and tolerability. A thorough preclinical PK assessment of antiseizure medications (ASMs) is therefore essential to evaluate the clinical potential. We tested protection against evoked seizures of prototype ASMs in conjunction with analysis of plasma and brain PK as a proof-of-principle study to enhance our understanding of drug efficacy and duration of action using rodent seizure models. METHODS: In vivo seizure protection assays were performed in adult male CF-1 mice and Sprague Dawley rats. Clobazam (CLB), N-desmethyl CLB (NCLB), carbamazepine (CBZ), CBZ-10,11-epoxide (CBZE), sodium valproate (VPA), and levetiracetam (LEV) concentrations were quantified in plasma and brain using liquid chromatography-tandem mass spectrometry. Mean concentrations of each analyte were calculated and used to determine PK parameters via noncompartmental analysis in Phoenix WinNonLin. RESULTS: NCLB concentrations were approximately 10-fold greater than CLB in mice. The antiseizure profile of CLB was partially sustained by NCLB in mice. CLB concentrations were lower in rats than in mice. CBZE plasma exposures were approximately 70% of CBZ in both mice and rats, likely contributing to the antiseizure effect of CBZ. VPA showed a relatively short half-life in both mice and rats, which correlated with a sharp decline in efficacy. LEV had a prolonged brain and plasma half-life, associated with a prolonged duration of action in mice. SIGNIFICANCE: The study demonstrates the utility of PK analyses for understanding the seizure protection time course in mice and rats. The data indicate that distinct PK profiles of ASMs between mice and rats likely drive differences in drug efficacy between rodent models.
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Anticonvulsivantes , Epilepsia , Masculino , Ratas , Ratones , Animales , Anticonvulsivantes/uso terapéutico , Anticonvulsivantes/farmacocinética , Epilepsia/tratamiento farmacológico , Ratas Sprague-Dawley , Levetiracetam/uso terapéutico , Carbamazepina/uso terapéutico , Convulsiones/tratamiento farmacológico , Clobazam/uso terapéutico , Benzodiazepinas/uso terapéuticoRESUMEN
This study investigated the roles of transient receptor potential (TRP) ankyrin-1 (TRPA1) and TRP vanilloid-3 (TRPV3) in regulating endoplasmic reticulum stress (ERS) and cytotoxicity in human bronchial epithelial cells (HBECs) treated with pneumotoxic wood smoke particulate matter (WSPM) and chemical agonists of each channel. Functions of TRPA1 and TRPV3 in pulmonary epithelial cells remain largely undefined. This study shows that TRPA1 activity localizes to the plasma membrane and endoplasmic reticulum (ER) of cells, whereas TRPV3 resides primarily in the ER. Additionally, treatment of cells using moderately cytotoxic concentrations of pine WSPM, carvacrol, and other TRPA1 agonists caused ERS as a function of both TRPA1 and TRPV3 activities. Specifically, ERS and cytotoxicity were attenuated by TRPA1 inhibition, whereas inhibiting TRPV3 exacerbated ERS and cytotoxicity. Interestingly, after treatment with pine WSPM, TRPA1 transcription was suppressed, whereas TRPV3 was increased. TRPV3 overexpression in HBECs conferred resistance to ERS and an attenuation of ERS-associated cell cycle arrest caused by WSPM and multiple prototypical ERS-inducing agents. Alternatively, short hairpin RNA-mediated knockdown of TRPV3, like the TRPV3 antagonist, exacerbated ERS. This study reveals previously undocumented roles for TRPA1 in promoting pathologic ERS and cytotoxicity elicited by pneumotoxic WSPM and TRPA1 agonists, and a unique role for TRPV3 in fettering pathologic facets of the integrated ERS response. SIGNIFICANCE STATEMENT: These findings provide new insights into how wood smoke particulate matter and other transient receptor potential ankyrin-1 (TRPA1) and transient receptor potential vanilloid-3 (TRPV3) agonists can affect human bronchial epithelial cells and highlight novel physiological and pathophysiological roles for TRPA1 and TRPV3 in these cells.
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Estrés del Retículo Endoplásmico/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Pulmón/efectos de los fármacos , Material Particulado/administración & dosificación , Humo/efectos adversos , Canal Catiónico TRPA1/metabolismo , Canales Catiónicos TRPV/metabolismo , Línea Celular , Cimenos/efectos adversos , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Células Epiteliales/metabolismo , Células HEK293 , Humanos , Pulmón/metabolismo , Pinus/efectos adversos , Canales de Potencial de Receptor Transitorio/metabolismo , Madera/efectos adversosRESUMEN
BACKGROUND: Initial trials of lung-targeted budesonide (0.25 mg/kg) in surfactant to prevent bronchopulmonary dysplasia (BPD) in premature infants have shown benefit; however, the optimal safe dose is unknown. METHODS: Dose-escalation study of budesonide (0.025, 0.05, 0.10 mg/kg) in calfactatant in extremely low gestational age neonates (ELGANs) requiring intubation at 3-14 days. Tracheal aspirate (TA) cytokines, blood budesonide concentrations, and untargeted blood metabolomics were measured. Outcomes were compared with matched infants receiving surfactant in the Trial Of Late SURFactant (TOLSURF). RESULTS: Twenty-four infants with mean gestational age 25.0 weeks and 743 g birth weight requiring mechanical ventilation were enrolled at mean age 6 days. Budesonide was detected in the blood of all infants with a half-life of 3.4 h. Of 11 infants with elevated TA cytokine levels at baseline, treatment was associated with sustained decrease (mean 65%) at all three dosing levels. There were time- and dose-dependent decreases in blood cortisol concentrations and changes in total blood metabolites. Respiratory outcomes did not differ from the historic controls. CONCLUSIONS: Budesonide/surfactant had no clinical respiratory benefit at any dosing levels for intubated ELGANs. One-tenth the dose used in previous trials had minimal systemic metabolic effects and appeared effective for lung-targeted anti-inflammatory action.
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Displasia Broncopulmonar/tratamiento farmacológico , Budesonida/administración & dosificación , Tensoactivos/administración & dosificación , Antiinflamatorios/farmacología , Peso al Nacer , Budesonida/sangre , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hidrocortisona/sangre , Recien Nacido Extremadamente Prematuro , Recién Nacido , Recien Nacido Prematuro , Masculino , Riesgo , Resultado del TratamientoRESUMEN
OBJECTIVE: Pharmacokinetics (PK) of antiseizure drugs differ considerably between rats and humans. Rodents require larger and more frequent doses to maintain therapeutic drug levels. This study uses the antiseizure drug (ASD) carbamazepine (CBZ) to validate the application of a previously described automated drug delivery system for delivering chronic oral medication to rats. METHODS: Treatment-naive, male Sprague-Dawley rats were treated with oral CBZ, 75 mg/kg every 6 hours for 10 days, via the automated feeder. Blood samples were collected on day 0 (acute), day 2 (steady-state), and day 9 (chronic) and used to measure plasma CBZ and carbamazepine-10,11-epoxide (CBZ-E) concentrations via high-performance liquid chromatography. The PK of CBZ and CBZ-E were modeled using Monolix v2018R1. The acute and chronic tolerability of CBZ was evaluated using the open field test. RESULTS: CBZ and CBZ-E concentrations were best described by a one-compartment parent-metabolite model with first-order absorption and elimination kinetics. Observed and predicted CBZ concentrations were maintained within the therapeutic window (4-12 µg/mL) for the duration of the study. There was no change in open-field test activity following acute or chronic oral dosing of 75 mg/kg CBZ compared to a pretreatment baseline (P > 0.4). SIGNIFICANCE: Oral administration of CBZ dosed q.i.d. in rats using an automated drug delivery system results in therapeutic concentrations of CBZ and its active metabolite. This study represents the first PK validation for this previously described preclinical drug delivery system.
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Anticonvulsivantes/farmacocinética , Carbamazepina/farmacocinética , Sistemas de Liberación de Medicamentos , Administración Oral , Animales , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
PURPOSE: Intravenous (IV) magnesium sulfate (MgSO4) is clinically useful as adjunct therapy in treating acute asthma exacerbations. Despite its clinical utility, the disposition of magnesium in children is poorly described. The purpose of this study is to describe the pharmacokinetics (PK) of ionized and total serum magnesium following IV MgSO4 administration in children with severe acute asthma. METHODS: Thirty-two children receiving 50 mg/kg IV MgSO4 for acute asthma exacerbations at Primary Children's Hospital in Salt Lake City, UT, were prospectively enrolled in the study. Blood samples were collected before, as well as 30 min and 2 h after each child's IV MgSO4 dose, and used to determine total serum and ionized magnesium concentrations. The collected data were analyzed using population PK techniques using NONMEM® software. RESULTS: Total serum magnesium concentrations were used to externally validate our previously published model constructed with retrospective data (median prediction error 10.3%, median absolute prediction error 18.1%). The mean (%CV) observed endogenous ionized magnesium concentration was calculated to be 6.0 mg/L (12%), approximately one third of the same value for endogenous total serum magnesium (17.6 mg/L (22%)) in this dataset. Weight was a significant predictor of both clearance and volume in a population PK model describing ionized magnesium concentrations. No adverse events were observed in this pediatric cohort. CONCLUSIONS: This prospective study supports and extends our previous PK analysis of total serum magnesium concentrations. Ionized and total serum magnesium followed similar PK profiles following IV MgSO4 administration in children. A single bolus infusion of IV MgSO4 was safe in this small sample of children receiving it for acute asthma.
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Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Sulfato de Magnesio/administración & dosificación , Modelos Biológicos , Enfermedad Aguda , Adolescente , Antiasmáticos/efectos adversos , Antiasmáticos/farmacocinética , Asma/fisiopatología , Niño , Preescolar , Femenino , Hospitalización , Humanos , Infusiones Intravenosas , Sulfato de Magnesio/efectos adversos , Sulfato de Magnesio/farmacocinética , Masculino , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Factores de TiempoRESUMEN
AIMS: Nicotine addiction is an issue faced by millions of individuals worldwide. As a result, nicotine replacement therapies, such as transdermal nicotine patches, have become widely distributed and used. While the pharmacokinetics of transdermal nicotine have been extensively described using noncompartmental methods, there are few data available describing the between-subject variability in transdermal nicotine pharmacokinetics. The aim of this investigation was to use population pharmacokinetic techniques to describe this variability, particularly as it pertains to the absorption of nicotine from the transdermal patch. METHODS: A population pharmacokinetic parent-metabolite model was developed using plasma concentrations from 25 participants treated with transdermal nicotine. Covariates tested in this model included: body weight, body mass index, body surface area (calculated using the Mosteller equation) and sex. RESULTS: Nicotine pharmacokinetics were best described with a one-compartment model with absorption based on a Weibull distribution and first-order elimination and a single compartment for the major metabolite, cotinine. Body weight was a significant covariate on apparent volume of distribution of nicotine (exponential scaling factor 1.42). After the inclusion of body weight in the model, no other covariates were significant. CONCLUSIONS: This is the first population pharmacokinetic model to describe the absorption and disposition of transdermal nicotine and its metabolism to cotinine and the pharmacokinetic variability between individuals who were administered the patch.
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Modelos Biológicos , Nicotina/administración & dosificación , Nicotina/farmacocinética , Agonistas Nicotínicos/administración & dosificación , Agonistas Nicotínicos/farmacocinética , Dispositivos para Dejar de Fumar Tabaco , Administración Cutánea , Adulto , Ensayos Clínicos como Asunto , Femenino , Humanos , Masculino , Nicotina/sangre , Agonistas Nicotínicos/sangre , Estudios Retrospectivos , Absorción Cutánea , Parche Transdérmico , Adulto JovenRESUMEN
PURPOSE: Intravenous (IV) magnesium sulfate (MgSO4) is used as adjunct therapy to treat acute asthma exacerbations. Despite its clinical use, there is a limited understanding of the disposition of magnesium in children. METHODS: To explore the pharmacokinetics (PK) of IV MgSO4 in this population, we collected retrospective data from 54 children who received IV MgSO4 for treatment of an acute asthma exacerbation at Primary Children's Hospital in Salt Lake City, UT. These data were analyzed using population PK modeling techniques in NONMEM® to determine sources of variability affecting the disposition of magnesium, as well as to predict the dose of IV MgSO4 needed to achieve clinical benefit. RESULTS: The covariate analysis found that only weight was a significant predictor of magnesium concentrations in children. Estimated model parameters suggested that magnesium exhibits a short serum half-life (2.7 h) in children. The average endogenous magnesium concentration (prior to administration of IV MgSO4) was estimated to be 21 mg/L. Simulated data suggested that doses between 50 and 75 mg/kg are required to achieve concentration-time profiles within a hypothesized target therapeutic range between 25 and 40 mg/L. CONCLUSIONS: These results provide new insight into the disposition of IV MgSO4 in children and provide dosing guidelines for future prospective studies of IV MgSO4 in children with acute asthma.
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Asma/tratamiento farmacológico , Sulfato de Magnesio/farmacocinética , Enfermedad Aguda , Adolescente , Niño , Preescolar , Femenino , Humanos , Sulfato de Magnesio/uso terapéutico , Masculino , Índice de Severidad de la EnfermedadRESUMEN
We present a 31-year-old female who had undergone an allogeneic bone marrow transplantation and who was started on intravenous posaconazole for pulmonary mycosis while undergoing continuous venovenous hemofiltration (CVVH). We performed steady-state pharmacokinetic evaluations for both posaconazole and sulfobutylether-ß-cyclodextrin (SBECD). SBECD was effectively removed by CVVH, with observed exposure similar to that for patients with moderate renal impairment. Intravenous posaconazole at standard doses may be utilized in critically ill patients undergoing CVVH without significant risk of SBECD accumulation.
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Enfermedad Crítica/terapia , Ciclodextrinas/sangre , Triazoles/sangre , beta-Ciclodextrinas/sangre , Administración Intravenosa , Adulto , Ciclodextrinas/administración & dosificación , Femenino , Hemofiltración , Humanos , Triazoles/administración & dosificación , beta-Ciclodextrinas/administración & dosificaciónRESUMEN
Sofosbuvir (SOF) is a highly efficacious and well-tolerated uridine nucleotide analog that inhibits the hepatitis C virus (HCV) NS5B polymerase enzyme. SOF is administered as a prodrug, which undergoes intracellular phosphorylation by host enzymes to a monophosphate, diphosphate, and finally a pharmacologically active triphosphate. In order to fully understand the clinical pharmacology of SOF, there is a great need to determine the intracellular phosphate concentrations of the drug. We describe the validation and utilization of a method to characterize SOF's disposition into various in vivo cell types, including hepatocytes, peripheral blood mononuclear cells (PBMC), and red blood cells (RBC). Standard bioanalytical validation criteria were applied to lysed cellular matrices, with a validated linear range of 50 to 50,000 fmol/sample for each phosphate moiety. The assay was utilized to collect the first data demonstrating concentrations of phosphorylated anabolites formed in PBMC, hepatocytes, and RBC in vivo during SOF therapy. Median concentrations in PBMC were 220 (range, 51.5 to 846), 70.2 (range, 25.8 to 275), and 859 (range, 54.5 to 6,756) fmol/10(6) cells in the monophosphate, diphosphate, and triphosphate fractions, respectively. In contrast, RBC triphosphate concentrations were much lower than those of PBMC, as the median concentration was 2.91 (range, 1.14 to 10.4) fmol/10(6) cells. The PBMC triphosphate half-life was estimated at 26 h using noncompartmental approaches, while nonlinear mixed-effect modeling was used to estimate a 69 h half-life for this moiety in RBC. The validated method and the data it generates provide novel insight into the cellular disposition of SOF and its phosphorylated anabolites in vivo.
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Antivirales/análisis , Sofosbuvir/análisis , Antivirales/farmacocinética , Cromatografía Líquida de Alta Presión , Eritrocitos/química , Semivida , Hepatitis C/sangre , Hepatitis C/metabolismo , Hepatocitos/química , Humanos , Monocitos/química , Dinámicas no Lineales , Fosfatos/análisis , Fosforilación , Control de Calidad , Reproducibilidad de los Resultados , Sofosbuvir/farmacocinética , Espectrometría de Masas en TándemRESUMEN
Ribavirin, a guanosine analog, is a broad-spectrum antiviral agent. Ribavirin has been a fundamental component of the treatment of hepatitis C virus (HCV) infection for decades, but there is a very limited understanding of the clinical pharmacology of this drug. Furthermore, it is associated with a major dose-limiting toxicity, hemolytic anemia. Ribavirin undergoes intracellular phosphorylation by host enzymes to ribavirin monophosphate (RMP), ribavirin diphosphate (RDP), and ribavirin triphosphate (RTP). The intracellular forms have been associated with antiviral and toxic effects in vitro, but the kinetics of these phosphorylated moieties have not been fully elucidated in vivo. We developed a model to characterize the plasma pharmacokinetics of ribavirin and the difference between intracellular phosphorylation kinetics in red cells (nonnucleated) and in peripheral blood mononuclear cells (nucleated). A time-independent two-compartment model with first-order absorption described the plasma data well. The cellular phosphorylation kinetics was described by a one-compartment model for RMP, with the formation rate driven by plasma concentrations and the first-order degradation rate. RDP and RTP rapidly reached equilibrium with RMP. Concomitant telaprevir use, inosine triphosphatase genetics, creatinine clearance, weight, and sex were significant covariates. The terminal ribavirin half-life in plasma and phosphorylated anabolites in cells was approximately 224 h. We found no evidence of time-dependent kinetics. These data provide a foundation for uncovering concentration-effect associations for ribavirin and determining the optimal dose and duration of this drug for use in combination with newer direct-acting HCV agents. (This study has been registered at ClinicalTrials.gov under registration no. NCT01097395.).
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Antivirales/farmacocinética , Hepatitis C Crónica/sangre , Ribavirina/farmacocinética , Adulto , Antivirales/sangre , Antivirales/uso terapéutico , Peso Corporal , Eritrocitos/metabolismo , Femenino , Semivida , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Oligopéptidos/uso terapéutico , Fosforilación , Población , Ribavirina/sangre , Ribavirina/uso terapéutico , Caracteres SexualesRESUMEN
OBJECTIVES: Ribavirin concentrations may impact hepatitis C virus (HCV) treatment outcome. We modelled ribavirin serum and intracellular ribavirin monophosphate (RBV-MP) and ribavirin triphosphate (RBV-TP) pharmacokinetics in red blood cells (RBC) using samples collected during the NIAID SPARE trial to explore associations with treatment outcome and the development of anaemia. PATIENTS AND METHODS: Individuals infected with HCV genotype 1 (GT1) received 400 mg of sofosbuvir and either low-dose or weight-based ribavirin as part of the NIAID SPARE trial. Concentrations were modelled using NONMEM and associated with treatment outcomes using unpaired t-tests or Pearson's rho correlations. RESULTS: Average day 14 RBV-MP concentrations were higher in subjects with haemoglobin nadir <10 g/dL relative to patients with haemoglobin nadir ≥10 g/dL (6.54 versus 4.48 pmol/10(6) cells; Pâ=â0.02). Additionally, day 14 RBV-MP average concentrations trended towards being higher in subjects that achieved sustained virological response (SVR) as compared with patients who relapsed (4.97 versus 4.09 pmol/10(6) cells; Pâ=â0.07). Receiver operating characteristic curves suggested day 14 RBV-MP concentration thresholds of 4.4 pmol/10(6) cells for SVR (Pâ=â0.06) and 6.1 pmol/10(6) cells for haemoglobin nadir <10 versus ≥10 g/dL (Pâ=â0.02), with sensitivity and specificity ≥60%. Dosing simulations showed that 800 mg of ribavirin once daily produced day 14 RBV-MP concentrations within the 4.4-6.1 pmol/10(6) cells range. CONCLUSIONS: RBV-MP concentrations in RBC at day 14 were related to anaemia and SVR. A therapeutic range was identified for RBV-MP in persons with HCV GT1 disease receiving 24 weeks of sofosbuvir plus ribavirin, suggesting a potential pharmacological basis for individualized ribavirin dosing in IFN-free regimens.
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Antivirales/administración & dosificación , Antivirales/farmacocinética , Eritrocitos/química , Ribavirina/administración & dosificación , Ribavirina/farmacocinética , Suero/química , Sofosbuvir/administración & dosificación , Adulto , Anciano , Anemia/inducido químicamente , Antivirales/efectos adversos , Femenino , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Ribavirina/efectos adversos , Resultado del Tratamiento , Carga ViralRESUMEN
INTRODUCTION: Intravenous (IV) voriconazole is not recommended in patients with creatinine clearance <50 ml/min to avoid potentially toxic accumulation of sulfobutylether-ß-cyclodextrin (SBECD). The purpose of this study was to evaluate the pharmacokinetics of SBECD, voriconazole, and voriconazole N-oxide in critically ill patients undergoing continuous renal replacement therapy (CRRT) and to determine if CRRT removes SBECD sufficiently to allow for the use of IV voriconazole without significant risk of SBECD accumulation. METHODS: This prospective, open-label pharmacokinetic study enrolled patients >18 years old receiving IV voriconazole for a known or suspected invasive fungal infection while undergoing CRRT. Serial blood and effluent samples were collected on days 1, 3, 5, 7, and every 3 to 5 days thereafter. SBECD, voriconazole, and voriconazole N-oxide plasma and effluent concentrations were measured by liquid chromatography-tandem mass spectrometry. Pharmacokinetic, pharmacodynamic, and pharmacogenetic analyses were conducted. RESULTS: Ten patients (mean ± standard deviation (SD)) 53 ± 11 years old, 50% male, 81 ± 14 kg, with Acute Physiologic and Chronic Health Evaluation II (APACHE II) scores of 31.5 ± 3.8 were evaluated. All patients underwent continuous venovenous hemofiltration (CVVH) with a median predilution replacement fluid rate of 36 (interquartile range (IQR) 32 to 37) ml/kg/hr and total ultrafiltration rate of 38 (IQR 34 to 39) ml/kg/hr. Mean ± SD voriconazole and SBECD dosages administered were 8.1 ± 2.1 mg/kg/day and 129 ± 33 mg/kg/day, respectively. Voriconazole plasma trough concentrations were >1 mg/L in all patients with CVVH accounting for only 15% of the total body clearance. CVVH accounted for 86% of the total body clearance of SBECD with the majority of the dose being recovered in the effluent. Minimal increases in dose normalized SBECD area under the concentration-time curve from 0 to 12 hours (AUC0-12) (4,484 ± 4,368 to 4,553 ± 2,880 mg*hr/L; P = 0.97) were observed after study day 1. CONCLUSIONS: CVVH effectively removed SBECD at a rate similar to the ultrafiltration rate. Voriconazole clearance by CVVH was not clinically significant. Standard dosages of IV voriconazole can be utilized in patients undergoing CVVH without significant risk of SBECD accumulation. TRIAL REGISTRATION: ClinicalTrials.gov NCT01101386 . Registered 6 April 2010.
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Antifúngicos/farmacocinética , Fallo Renal Crónico/tratamiento farmacológico , Terapia de Reemplazo Renal , Terapéutica/métodos , Voriconazol/farmacocinética , beta-Ciclodextrinas/farmacocinética , Adulto , Enfermedad Crítica , Humanos , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Terapéutica/efectos adversos , beta-Ciclodextrinas/toxicidadRESUMEN
Sialorrhea or drooling is a common problem in children and adults with neurodevelopmental disorders. It can negatively impact the quality of life due to its physical and psychological manifestations. Providers commonly prescribe atropine eye drops for topical administration to the oral mucosa, as an off-label treatment to manage sialorrhea. However, the off-label use of atropine eye drops can be associated with medication and dosing errors and systemic side effects. To address these limitations of treatment, we developed a mucoadhesive topical oral gel formulation of atropine as an alternative route to off-label administration of atropine eye drops. In this clinical pharmacokinetic (PK) study, we evaluated the safety and PK of atropine gel (0.01% w/w) formulation after single-dose administration to the oral mucosa in 10 healthy volunteers. The PK data showed that after topical administration to the oral mucosa, atropine followed a two-compartment PK profile. The maximum plasma concentration and area under the curve extrapolated to infinite time were 0.14 ng/mL and 0.74 h·ng·mL-1 , respectively. The absorption rate constant calculated by the compartmental analysis was 0.4 h-1 . Safety parameters, such as heart rate, blood pressure, and oxygen saturation, did not significantly change before and after administration of the gel formulation, and no adverse events were observed in all participants who received atropine gel. These data indicate that atropine gel formulation has a satisfactory PK profile, is well-tolerated at the dose studied, and can be further considered for clinical development as a drug product to treat sialorrhea.
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Calidad de Vida , Sialorrea , Adulto , Niño , Humanos , Voluntarios Sanos , Sialorrea/tratamiento farmacológico , Área Bajo la Curva , Soluciones Oftálmicas/efectos adversos , Derivados de Atropina , Administración OralRESUMEN
BACKGROUND: Partial-thickness skin wounds are some of the most painful injuries due to large areas of exposed nerve endings. These injuries often require systemic opioid treatments to manage pain adequately. However, in 2021 alone, the CDC reported nearly 17,000 prescription opioid-related deaths in the USA, highlighting the ongoing need for non-opioid treatment strategies. In this manuscript, we developed a novel single-application ropivacaine-eluting primary wound dressing that could provide sustained ropivacaine delivery to partial-thickness wounds and assessed its in vivo feasibility for prolonged non-opioid analgesia. METHODS: Sustained release of ropivacaine from a poly(lactide-co-e-caprolactone) matrix was first optimized in vitro using dissolution testing and a Box Behnken design of experiments. The optimized dressing was then tested against a clinical control silicone dressing in a porcine partial-thickness wound study to assess analgesic effect, pharmacokinetics, and wound healing. RESULTS: The ropivacaine-eluting dressing showed a moderate analgesic effect in vivo, where normalized single pinprick scores significantly improved pain over the testing period (4-168h) (control vs treatment: 232±25% vs 145±16%, p<0.0003). Ropivacaine blood plasma levels peaked at 8 hours post-treatment, with a maximum concentration of 246 ± 74 ng/mL. No significant differences in wound healing were found when compared to control. CONCLUSION: The ropivacaine-loaded poly(lactide-co-e-caprolactone)-based wound dressing provided sustained delivery of ropivacaine to partial-thickness skin wounds and enhanced analgesic effect compared to a clinical standard control dressing.
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AIM: The objective of this study was to determine the extent to which the CYP2C8*3 allele influences pharmacokinetic variability in the drug-drug interaction between gemfibrozil (CYP2C8 inhibitor) and pioglitazone (CYP2C8 substrate). METHODS: In this randomized, two phase crossover study, 30 healthy Caucasian subjects were enrolled based on CYP2C8*3 genotype (n = 15, CYP2C8*1/*1; n = 15, CYP2C8*3 carriers). Subjects received a single 15 mg dose of pioglitazone or gemfibrozil 600 mg every 12 h for 4 days with a single 15 mg dose of pioglitazone administered on the morning of day 3. A 48 h pharmacokinetic study followed each pioglitazone dose and the study phases were separated by a 14 day washout period. RESULTS: Gemfibrozil significantly increased mean pioglitazone AUC(0,∞) by 4.3-fold (P < 0.001) and there was interindividual variability in the magnitude of this interaction (range, 1.8- to 12.1-fold). When pioglitazone was administered alone, the mean AUC(0,∞) was 29.7% lower (P = 0.01) in CYP2C8*3 carriers compared with CYP2C8*1 homozygotes. The relative change in pioglitazone plasma exposure following gemfibrozil administration was significantly influenced by CYP2C8 genotype. Specifically, CYP2C8*3 carriers had a 5.2-fold mean increase in pioglitazone AUC(0,∞) compared with a 3.3-fold mean increase in CYP2C8*1 homozygotes (P = 0.02). CONCLUSION: CYP2C8*3 is associated with decreased pioglitazone plasma exposure in vivo and significantly influences the pharmacokinetic magnitude of the gemfibrozil-pioglitazone drug-drug interaction. Additional studies are needed to evaluate the impact of CYP2C8 genetics on the pharmacokinetics of other CYP2C8-mediated drug-drug interactions.
Asunto(s)
Hidrocarburo de Aril Hidroxilasas/genética , Gemfibrozilo/farmacología , Hipolipemiantes/farmacología , Polimorfismo Genético , Tiazolidinedionas/farmacocinética , Adulto , Área Bajo la Curva , Estudios Cruzados , Citocromo P-450 CYP2C8 , Interacciones Farmacológicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , PioglitazonaRESUMEN
BACKGROUND: Children managed for asthma in an emergency department (ED) may be less likely to be hospitalized if they receive intravenous magnesium sulfate (IVMg). Asthma guidelines recommend IVMg for severely sick children but note a lack of evidence to support this recommendation. All previous trials of IVMg in children with asthma have been too small to answer whether IVMg is effective and safe. A few major questions remain about IVMg. First, it has not been tested early in the course of ED treatment, when the impact on hospitalization would be greatest. Second, the clinical impact of hypotension, a known adverse effect of IVMg, has not been well characterized in previous research. Third, no trials have compared different IVMg doses or serial serum magnesium (total and ionized) concentrations to optimize dosing, so the most effective dose is unknown. A large, conclusive, randomized, placebo-controlled clinical trial of IVMg might be challenging due to the need to enroll and complete study procedures quickly, a lack of understanding of blood pressure changes after IVMg, and a lack of pharmacologic information to guide the optimal doses of IVMg to be tested. Therefore, a pilot study to inform the above gaps is warranted before conducting a definitive trial. OBJECTIVE: The objectives of this study are to (1) demonstrate the feasibility of enrolling children with severe acute asthma in the ED in a multicenter, randomized controlled trial of a placebo, low-dose IVMg, or high-dose IVMg; (2) demonstrate the feasibility of timely delivery of study medication, assessment of blood pressure, and evaluation of adverse events in a standardized protocol; and (3) externally validate a previously constructed pharmacokinetic model and develop a combined pharmacokinetic/pharmacodynamic model for IVMg using magnesium (total and ionized) serum concentrations and their correlation with measures of efficacy and safety. METHODS: This pilot trial tests procedures and gathers information to plan a definitive trial. The pilot trial will enroll as many as 90 children across 3 sites, randomize each child to 1 of 3 study arms, measure blood pressure frequently, and collect 3 blood samples from each participant with corresponding clinical asthma scores. RESULTS: The project was funded by the National Heart, Lung, and Blood Institute (1 R34HL152047-2) in March 2022. Enrollment began in September 2022, and 43 children have been enrolled as of April 2023. We will submit the results for publication in late 2023. CONCLUSIONS: The results of this study will guide the planning of a large, definitive, multicenter trial powered to evaluate if IVMg reduces hospitalization. Blood pressure measurements will inform a monitoring plan for the larger trial, and blood samples and asthma scores will be used to validate pharmacologic models to select the optimal dose of IVMg to be evaluated in the definitive trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT05166811; https://clinicaltrials.gov/ct2/show/NCT05166811. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/48302.
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STUDY OBJECTIVE: The immunosuppressant tacrolimus is a first-line agent to prevent graft rejection following pediatric heart transplant; however, it suffers from extensive inter-patient variability and a narrow therapeutic window. Personalized tacrolimus dosing may improve transplant outcomes by more efficiently achieving and maintaining therapeutic tacrolimus concentrations. We sought to externally validate a previously published population pharmacokinetic (PK) model that was constructed with data from a single site. DATA SOURCE: Data were collected from Seattle, Texas, and Boston Children's Hospitals, and assessed using standard population PK modeling techniques in NONMEMv7.2. MAIN RESULTS: While the model was not successfully validated for use with external data, further covariate searching identified weight (p < 0.0001 on both volume and elimination rate) as a model-significant covariate. This refined model acceptably predicted future tacrolimus concentrations when guided by as few as three concentrations (median prediction error = 7%; median absolute prediction error = 27%). CONCLUSION: These findings support the potential clinical utility of a population PK model to provide personalized tacrolimus dosing guidance.