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

Analysis of drug adverse events in elderly patients based on the Japanese Adverse Drug Event Report Database

WHAT IS KNOWN AND OBJECTIVE

Compared with the general adult population, pharmacokinetics and changes in drug responsiveness occur to a greater extent in the elderly. Interactions may occur between drugs used in combination to treat various diseases and may cause adverse events (AEs). We conducted a cross-sectional risk assessment of AEs in elderly patients based on information gathered from Japanese medical practices with the goal of obtaining information that will contribute to optimizing pharmacotherapy.

METHODS

The Japanese Adverse Drug Event Report database was used to determine the incidence of AEs in elderly patients (aged 80 years or older) compared with patients aged less than 80 years old by evaluating the reporting odds ratio using the data obtained from reports.

RESULTS AND DISCUSSION

Hypnotics and anxiolytics, as well as anticoagulants and theophylline, were identified as groups of drugs that warrant special attention in the elderly. Hypnotics and anxiolytics, especially those that are short-acting, tend to cause delirium and geriatric syndromes including falls and fractures. With respect to anticoagulants, no increase in the risk of bleeding was evident and the dose was believed to be properly adjusted; however, there was an increased risk of anemia. Theophylline toxicity tended to occur more frequently in the elderly, suggesting the need for drug monitoring.

WHAT IS NEW AND CONCLUSION

Based on these cross-sectional studies, the evaluation of the risk of AEs for drugs commonly used in the elderly based on near real-world information was achieved.

A Physiologically-Based Pharmacokinetic Model to Describe Ciprofloxacin Pharmacokinetics Over the Entire Span of Life

Background

Physiologically-based pharmacokinetic (PBPK) modeling has received growing interest as a useful tool for the assessment of drug pharmacokinetics by continuous knowledge integration.

Objective

The objective of this study was to build a ciprofloxacin PBPK model for intravenous and oral dosing based on a comprehensive literature review, and evaluate the predictive performance towards pediatric and geriatric patients.

Methods

The aim of this report was to establish confidence in simulations of the ciprofloxacin PBPK model along the development process to facilitate reliable predictions outside of the tested adult age range towards the extremes of ages. Therefore, mean data of 69 published clinical trials were identified and integrated into the model building, simulation and verification process. The predictive performance on both ends of the age scale was assessed using individual data of 258 subjects observed in own clinical trials.

Results

Ciprofloxacin model verification demonstrated no concentration-related bias and accurate simulations for the adult age range, with only 4.8% of the mean observed data points for intravenous administration and 12.1% for oral administration being outside the simulated twofold range. Predictions towards the extremes of ages for the area under the plasma concentration–time curve (AUC) and the maximum plasma concentration (C_max) over the entire span of life revealed a reliable estimation, with only two pediatric AUC observations outside the 90% prediction interval.

Conclusion

Overall, this ciprofloxacin PBPK modeling approach demonstrated the predictive power of a thoroughly informed middle-out approach towards age groups of interest to potentially support the decision-making process.

Electronic supplementary material

The online version of this article (10.1007/s40262-018-0661-6) contains supplementary material, which is available to authorized users.