Evidence Hub

Pharmacokinetic-pharmacodynamic modeling using combined time-kill data for meropenem and colistin or polymyxin B combination effects in Acinetobacter baumannii

Soeorg H, Lyu S, Kloprogge F, Standing JF

Antimicrobial agents and chemotherapy, 2026

Abstract

Acinetobacter baumannii is a high-priority pathogen with increasing antimicrobial resistance levels, requiring combination treatment. We aimed to develop a pharmacokinetic-pharmacodynamic model of meropenem with colistin/polymyxin B against A. baumannii based on a systematic review of time-kill experiments to inform the effectiveness of this combination. PubMed was systematically searched for all studies describing time-kill experiments of meropenem and colistin/polymyxin B combinations against A. baumannii. Time-kill data and strain metadata were extracted. A pharmacokinetic-pharmacodynamic model with logistic growth, sigmoidal Emax killing functions of monotherapies, time-dependent attenuation of drug effect, and general pharmacodynamic interaction for the combination effect was fitted. Simulations were performed to produce dose recommendations. A total of 21 eligible papers were found reporting data from 369 experiments on 53 strains. Minimum inhibitory concentration (MIC) on EC50 (concentration achieving half-maximum killing), inoculum on Emax (maximum killing rate), and beta-lactamases on Emax for meropenem were covariates and both drugs. EC50 of both drugs included interisolate variability. The model showed that colistin/polymyxin B increased meropenem Emax and decreased its EC50. No interisolate variability in the interaction was supported by the model. Simulations showed that in pneumonia, undetectable growth at 24 h can be achieved with a probability of >90% only in…

How strong is the evidence?

Evidence Hub reads this as a systematic review. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free