scholarly journals O07 Predictive performance of a physiologically based pharmacokinetic model of caffeine in the preterm population

2019 ◽  
Vol 104 (6) ◽  
pp. e3.2-e3
Author(s):  
A Pansari ◽  
K Abduljalil ◽  
T Johnson

BackgroundCaffeine has been extensively used in the treatment of apnoea in premature infants,1 its disposition varies with postnatal age2 and can differ markedly between premature and term neonates.MethodsThe Preterm population within the Simcyp Simulator V18R1 population library was used to replicate clinical studies to predict caffeine exposure after single3 and multiple4 intravenous administration to preterm neonates of gestational weeks 28.5 and 29 (28–33) respectively, ranging in postnatal age of 3–30 days and 0–3 days respectively. Predictive performance of the Physiologically Based Pharmacokinetic Model (PBPK) was evaluated by comparing the simulated to the clinical results. A population simulation was performed for the single dose study as only pharmacokinetic parameters were available. However, for multiple doses study, where individual plasma concentration-time profile data were available, simulations were performed for each individual.ResultsPBPK model predictions for caffeine in preterm neonates were in good agreement with the clinical observations. In the case of single dose administration, the ratios of predicted vs observed mean Volume of distribution (Vss), peak plasma concentration (Cmax), Clearance (CL) and Half-life (t1/2) were 1, 1.2, 1 and 1.1, respectively. Individual predicted concentration-time profiles following multiple dose administration were in close agreement with the observed data for all 16 subjects, overall 95% of individual observed data points were within the 5th and 95th percentile of predicted plasma concentration-time profile.ConclusionsThe predictive performance of preterm PBPK models for caffeine was found to be appropriate. A similar PBPK approach can be utilized in the clinics for the accurate prediction of pharmacokinetic parameters and plasma concentrations and for dosage adjustment to attain specific plasma concentrations of drugs in premature population.ReferencesGiacoia, et al. Effects of formula feeding on oral absorption of caffeine in premature infants. Dev Pharmacol Ther 1989; 12:205–210.Johnson, et al. Prediction of the clearance of eleven drugs and associated variability in neonates, infants and children. Clin Pharmacokinet 2006; 45(9):931–56.Aranda, et al. Population Pharmacokinetic profile of caffeine in the premature newborn infant with apnea; The Journal of Pediatrics 1979; 94(4.):663–668.Lee, et al. Caffeine in apnoeic asian neonates: a sparse data analysis. Br J Clin Pharmacol 2002; 54:31–37.Disclosure(s)Nothing to disclose

2020 ◽  
Vol 37 (12) ◽  
Author(s):  
Hannah Britz ◽  
Nina Hanke ◽  
Mitchell E. Taub ◽  
Ting Wang ◽  
Bhagwat Prasad ◽  
...  

Abstract Purpose To provide whole-body physiologically based pharmacokinetic (PBPK) models of the potent clinical organic anion transporter (OAT) inhibitor probenecid and the clinical OAT victim drug furosemide for their application in transporter-based drug-drug interaction (DDI) modeling. Methods PBPK models of probenecid and furosemide were developed in PK-Sim®. Drug-dependent parameters and plasma concentration-time profiles following intravenous and oral probenecid and furosemide administration were gathered from literature and used for model development. For model evaluation, plasma concentration-time profiles, areas under the plasma concentration–time curve (AUC) and peak plasma concentrations (Cmax) were predicted and compared to observed data. In addition, the models were applied to predict the outcome of clinical DDI studies. Results The developed models accurately describe the reported plasma concentrations of 27 clinical probenecid studies and of 42 studies using furosemide. Furthermore, application of these models to predict the probenecid-furosemide and probenecid-rifampicin DDIs demonstrates their good performance, with 6/7 of the predicted DDI AUC ratios and 4/5 of the predicted DDI Cmax ratios within 1.25-fold of the observed values, and all predicted DDI AUC and Cmax ratios within 2.0-fold. Conclusions Whole-body PBPK models of probenecid and furosemide were built and evaluated, providing useful tools to support the investigation of transporter mediated DDIs.


2017 ◽  
Vol 12 (4) ◽  
pp. 1934578X1701200 ◽  
Author(s):  
Shihua Xing ◽  
Mengyue Wang ◽  
Ying Peng ◽  
Xiaobo Li

Baicalin and wogonoside are two of the most abundant flavonoid glycosides in the root of Scutellaria baicalensis Georgi, which is a widely used peroral herbal medicine with anticancer, antiviral, antibacterial and anti-inflammatory properties. In the present study, the effects of intestinal microecology on the metabolism and pharmacokinetics of orally administered baicalin and wogonoside were investigated by UPLC-QTOF/MS measurement of the difference in metabolites between normal and antibiotic-pretreated rats. In the antibiotic-pretreated rats, the plasma concentration-time profile and pharmacokinetic parameters of the two flavonoid glycosides and their relevant aglycone forms were significantly changed compared with those in normal rats. Further, hydrolysis and glucuronidated metabolites were not detected in the cecum contents and urine samples from antibiotic-pretreated rats. These results suggested that intestinal microbiota may play a key role in the pharmacokinetics and metabolism of peroral baicalin and wogonoside. According to our findings, it is recommended that the root of S. baicalensis should not be co-administered with antibiotics in clinical use.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Chunchao Han ◽  
Bo Cui

The purpose of this study is to investigate the bioavailability and glycaemic metabolism of cinnamon oil (CIO) carried by liquid-loadable tablets (CIO-LLTs), the carrier of a CIO self-emulsifying formulation (CIO-LS). The results of tests performed to evaluate the physical properties of the CIO-LLT complied with Chinese Pharmacopeia (2010). The release profile suggested that the CIO-LLT preserved the enhancement of in vitro dissolution of cio. After orally administration, the plasma concentration-time profile and pharmacokinetic parameters suggested that a significant increase (P<0.0001) in theCmax, AUC andFwere observed in the CIO-LLT. The blood glucose and the HbA1c were significantly decreased in alloxan-induced hyperglycemic rats (P<0.05,P<0.01, resp.), while the level of insulin secretion was markedly elevated in alloxan-induced hyperglycemic rats (P<0.05). The alloxan-damaged pancreaticβ-cells of the rats were partly recovered gradually after the rats were administered with CIO-LLT 45 days later. CIO-LLT could improve the bioavailability and glycaemic metabolism of CIO.


2021 ◽  
Vol 12 ◽  
Author(s):  
Zhongxia Tan ◽  
Youxi Zhang ◽  
Chao Wang ◽  
Le Sun

The aim of this study was to develop physiologically based pharmacokinetic (PBPK) models capable of simulating cefadroxil concentrations in plasma and tissues in mouse, rat, and human. PBPK models in this study consisted of 14 tissues and 2 blood compartments. They were established using measured tissue to plasma partition coefficient (Kp) in mouse and rat, absolute expression levels of hPEPT1 along the entire length of the human intestine, and the transporter kinetic parameters. The PBPK models also assumed that all the tissues were well-stirred compartments with perfusion rate limitations, and the ratio of the concentration in tissue to the unbound concentration in plasma is identical across species. These PBPK models were validated strictly by a series of observed plasma concentration–time profile data. The average fold error (AFE) and absolute average fold error (AAFE) values were all less than 2. The models’ rationality and accuracy were further demonstrated by the almost consistent Vss calculated by the PBPK model and noncompartmental method, as well as the good allometric scaling relationship of Vss and CL. The model suggests that hPEPT1 is the major transporter responsible for the oral absorption of cefadroxil in human, and the plasma concentration–time profiles of cefadroxil were not sensitive to dissolution rate faster than T85% = 2 h. The cefadroxil PBPK model in human is reliable and can be used to predict concentration–time profile at infected tissue. It may be useful for dose selection and informative decision-making during clinical trials and dosage form design of cefadroxil and provide a reference for the PBPK model establishment of hPEPT1 substrate.


2016 ◽  
Vol 19 (2) ◽  
pp. 239 ◽  
Author(s):  
Helal H. Alsulimani ◽  
Jonghan Kim ◽  
Shabnam N. Sani

Purpose. To develop a quantitative pharmacokinetic model to characterize the disposition of methotrexate (MTX) at tumor site in tumor-bearing mice and to predict MTX concentrations in the human tumor. Methods. The plasma profiles of MTX were obtained from normal mice, while microdialysis technique was employed to characterize the time course of MTX in tumor from breast tumor-bearing mice. Disposition profiles of plasma and tumor were analyzed by a hybrid physiologically-based pharmacokinetic (hPBPK) model that incorporates physiologically-relevant parameters such as tumor blood flow and volume, while plasma concentrations were used as a forcing input into the vascular-interstitial spaces of the tumor. The plasma profiles were initially described by a biexponential decay model to obtain a forcing function that enters into the vascular-interstitial spaces in the tumor. Using a defined forcing function, the tumor free concentrations were fitted to the hPBPK model. Based on the model developed, sensitivity analysis was conducted with a perturbation of PK parameters to predict different scenarios of intratumoral MTX transport. The relevant physiological PK parameters from the mouse model were then scaled-up and utilized to simulate human tumor concentrations. Results. The mouse hPBPK model adequately characterized the concentration-time profiles of MTX in both plasma and tumor and produced various transfer rate constants between plasma and tumor. Our model was also able to reasonably predict MTX concentrations in the human tumor when human physiological data were utilized. Conclusions. The hPBPK model was able to quantitatively characterize the atypical transport of MTX in the tumor, supporting the idea that microdialysis is a valuable tool to study tumor biodistribution of drugs and to predict tumor concentrations in humans based on the pre-clinical data. This information can ultimately aid in the development of anticancer drugs with improved PK profiles. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.


2019 ◽  
Vol 104 (6) ◽  
pp. e52.2-e53
Author(s):  
F Salem ◽  
K Abduljalil ◽  
T Johnson

BackgroundRaltegravir is a drug used to treat patients with HIV infection. Understanding the disposition kinetics including the ontogeny of the major metabolic enzyme (UGT1A1) is important in prediction of raltaeravir pharmacokinetics in paediatric patients.MethodsSim-Raltegravir compound file in Simcyp simulator version 18 was used to predict pharmacokinetics in paediatric subjects aged 4 weeks to 6 months, 0.5 to 2, 2 to 6 and 6 to 12 years. Details of trial design were matched as closely as possible with a clinical study.1 Rate of absorption and variability in first order absorption model within Simcyp were set to the reported values. Predicted plasma concentration time profiles with 5th and 95th percentile were compared with observations.ResultsThe predicted vs. observed geometric mean area under plasma concentration-time profile of raltegravir was 18.4 vs. 22.3 µM.h in subjects 4 weeks to 6 months and 16.5 vs. 19.8 µM.h in those 0.5 to 2 years old. In 2 to 6 and 6 to 12 year olds around 80% and 85% of observed data were within 5th and 95th percentile of the predictions.ConclusionThe results show that the UGT1A1 ontogeny profile in the Simcyp version 18 adequately addressed age-related differences in pharmacokinetics of raltegravir.ReferenceRizk, M., et al, J Clin Pharmacol 2015; 55(7):748–56Disclosure(s)Nothing to disclose


2002 ◽  
Vol 2 ◽  
pp. 1369-1378 ◽  
Author(s):  
Tom B. Vree ◽  
Eric Dammers ◽  
Eri van Duuren

The aims of this investigation were to calculate the pharmacokinetic parameters and to identify parameters, based on individual plasma concentration-time curves of amoxicillin and clavulanic acid in cats, that may govern the observed differences in absorption of both drugs. The evaluation was based on the data from plasma concentration-time curves obtained following a single-dose, open, randomised, two-way crossover phase-I study, each involving 24 female cats treated with two Amoxi-Clav formulations (formulation A was Clavubactin® and formulation was B Synulox® ; 80/20 mg, 24 animals, 48 drug administrations). Plasma amoxicillin and clavulanic acid concentrations were determined using validated bioassay methods. The half-life of elimination of amoxicillin is 1.2 h (t1/2= 1.24 ± 0.28 h, Cmax= 12.8 ± 2.12 μg/ml), and that of clavulanic acid 0.6 h (t1/2= 0.63 ± 0.16 h, Cmax= 4.60 ± 1.68 μg/ml). There is a ninefold variation in the AUCtof clavulanic acid for both formulations, while the AUCtof amoxicillin varies by a factor of two. The highest clavulanic acid AUCtvalues indicate the best absorption; all other data indicate less absorption. Taking into account that the amoxicillin–to–clavulanic acid dose ratio in the two products tested was 4:1, the blood concentration ratios may actually vary much more, apparently without compromising the products’ high efficacy against susceptible microorganisms.


Author(s):  
Armin Sadighi ◽  
Lorenzo Leggio ◽  
Fatemeh Akhlaghi

Abstract Aims A physiologically based pharmacokinetic (PBPK) modeling approach was used to simulate the concentration-time profile of ethanol (EtOH) in stomach, duodenum, plasma and other tissues upon consumption of beer and whiskey under fasted and fed conditions. Methods A full PBPK model was developed for EtOH using the advanced dissolution, absorption and metabolism (ADAM) model fully integrated into the Simcyp Simulator® 15 (Simcyp Ltd., Sheffield, UK). The prediction performance of the developed model was verified and the EtOH concentration-time profile in different organs was predicted. Results Simcyp simulation showed ≤ 2-fold difference in values of EtOH area under the concentration-time curve (AUC) in stomach and duodenum as compared to the observed values. Moreover, the simulated EtOH maximum concentration (Cmax), time to reach Cmax (Tmax) and AUC in plasma were comparable to the observed values. We showed that liver is exposed to the highest EtOH concentration, faster than other organs (Cmax = 839.50 mg/L and Tmax = 0.53 h), while brain exposure of EtOH (AUC = 1139.43 mg·h/L) is the highest among all other organs. Sensitivity analyses (SAs) showed direct proportion of EtOH rate and extent of absorption with administered EtOH dose and inverse relationship with gastric emptying time (GE) and steady-state volume of distribution (Vss). Conclusions The current PBPK model approach might help with designing in vitro experiments in the area of alcohol organ damage or alcohol-drug interaction studies.


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