Dataset Information

Application of a Physiologically Based Pharmacokinetic Model to Study Theophylline Metabolism and Its Interactions With Ciprofloxacin and Caffeine.

ABSTRACT: Theophylline is a commonly used bronchodilator. However, due to its narrow therapeutic range, moderate elevation of serum concentration can result in adverse drug reactions (ADRs). ADRs occur because of interhuman pharmacokinetic variability and interactions with coprescribed medicines. We developed a physiologically based pharmacokinetic (PBPK) model of theophylline, caffeine, and ciprofloxacin metabolisms to: examine theophylline pharmacokinetic variability, and predict population-level outcomes of drug-drug interactions (DDIs). A simulation-based equation for personalized dosing of theophylline was derived. Simulations of DDI show that calculated personalized doses are safe even after cotreatment with large doses of strong inhibitors. Simulations of adult populations indicate that the elderly are most susceptible to ADRs stemming from theophylline-ciprofloxacin and theophylline-caffeine interactions. Females, especially Asians, due to their smaller average size, are more susceptible to DDI-induced ADRs following typical dosing practices. Our simulations also show that the higher adipose and lower muscle fractions in females significantly alter the pharmacokinetics of theophylline or ciprofloxacin.

SUBMITTER: Navid A

PROVIDER: S-EPMC4761233 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Application of a Physiologically Based Pharmacokinetic Model to Study Theophylline Metabolism and Its Interactions With Ciprofloxacin and Caffeine.

Navid A A Ng D M DM Wong S E SE Lightstone F C FC

CPT: pharmacometrics & systems pharmacology 20160216 2

Theophylline is a commonly used bronchodilator. However, due to its narrow therapeutic range, moderate elevation of serum concentration can result in adverse drug reactions (ADRs). ADRs occur because of interhuman pharmacokinetic variability and interactions with coprescribed medicines. We developed a physiologically based pharmacokinetic (PBPK) model of theophylline, caffeine, and ciprofloxacin metabolisms to: examine theophylline pharmacokinetic variability, and predict population-level outcom ...[more]

PMID: 26933518

Similar Datasets

Project description:Eliglustat is a glucosylceramide synthase inhibitor indicated as a long-term substrate reduction therapy for adults with type 1 Gaucher disease, a lysosomal rare disease. It is primarily metabolized by cytochrome P450 2D6 (CYP2D6), and variants in the gene encoding this enzyme are important determinants of eliglustat pharmacokinetics (PK) and drug-drug interactions (DDIs). The existing drug label addresses the DDIs to some extent but has omitted scenarios where both metabolizing CYPs (2D6 and 3A4) are mildly or moderately inhibited. The objectives of this study were (i) to develop and validate an eliglustat physiologically-based pharmacokinetic (PBPK) model with and without drug interactions, (ii) to simulate untested DDI scenarios, and (iii) to explore potential dosing flexibility using lower dose strength of eliglustat (commercially not available). PK data from healthy adults receiving eliglustat with or without interacting drugs were obtained from literature and used for the PBPK model development and validation. The model-predicted single-dose and steady-state maximum concentration (Cmax ) and area under the concentration-time curve (AUC) of eliglustat were within 50-150% of the observed values when eliglustat was administered alone or coadministered with ketoconazole or paroxetine. Then as model-based simulations, we illustrated eliglustat exposure as a victim of interaction when coadministered with fluvoxamine following the US Food and Drug Administration (FDA) dosing recommendations. Second, we showed that with lower eliglustat doses (21 mg, 42 mg once daily) the exposure in participants of intermediate and poor metabolizer phenotypes was within the outlined safety margin (Cmax <250 ng/mL) when eliglustat was administered with ketoconazole, where the current recommendation is a contraindication of coadministration (84 mg). The present study demonstrated that patients with CYP2D6 deficiency may benefit from lower doses of eliglustat.

Project description:Background: Voriconazole is a potent antifungal drug with complex pharmacokinetics caused by time-dependent inhibition and polymorphisms of metabolizing enzymes. It also exhibits different pharmacokinetic characteristics between adults and children. An understanding of these alterations in pharmacokinetics is essential for pediatric dose optimization. Objective: To determine voriconazole plasma exposure in the pediatric population and further investigate optimal dosage regimens. Methods: An adult and pediatric physiologically based pharmacokinetic (PBPK) model of voriconazole, integrating auto-inhibition of cytochrome P450 3A4 (CYP3A4) and CYP2C19 gene polymorphisms, was developed. The model was evaluated with visual predictive checks and quantitative measures of the predicted/observed ratio of the area under the plasma concentration-time curve (AUC) and maximum concentration (Cmax). The validated pediatric PBPK model was used in simulations to optimize pediatric dosage regimens. The probability of reaching a ratio of free drug (unbound drug concentration) AUC during a 24-h period to minimum inhibitory concentration greater than or equal to 25 (fAUC24h/MIC ≥ 25) was assessed as the pharmacokinetic/pharmacodynamic index. Results: The developed PBPK model well represented voriconazole's pharmacokinetic characteristics in adults; 78% of predicted/observed AUC ratios and 85% of Cmax ratios were within the 1.25-fold range. The model maintained satisfactory prediction performance for intravenous administration in pediatric populations after incorporating developmental changes in anatomy/physiology and metabolic enzymes, with all predicted AUC values within 2-fold and 73% of the predicted Cmax within 1.25-fold of the observed values. The simulation results of the PBPK model suggested that different dosage regimens should be administered to children according to their age, CYP2C19 genotype, and infectious fungal genera. Conclusion: The PBPK model integrating CYP3A4 auto-inhibition and CYP2C19 gene polymorphisms successfully predicted voriconazole pharmacokinetics during intravenous administration in children and could further be used to optimize dose strategies. The infectious fungal genera should be considered in clinical settings, and further research with large sample sizes is required to confirm the current findings.

Dataset Information

Application of a Physiologically Based Pharmacokinetic Model to Study Theophylline Metabolism and Its Interactions With Ciprofloxacin and Caffeine.

Publications

Application of a Physiologically Based Pharmacokinetic Model to Study Theophylline Metabolism and Its Interactions With Ciprofloxacin and Caffeine.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets