This study aimed to characterize the interstitial tissue fluid and plasma pharmacokinetics of meropenem in obese and non-obese patients followed by evaluation of commonly used dosing regimens via probability of target attainment analysis.

Adequacy of pharmacokinetic/pharmacodynamic targets: four times the minimum inhibitory concentration in probability of target attainment analysis for continuous infusions was corroborated in obese and non-obese patients based on lower meropenem interstitial tissue fluid versus plasma exposure.

Treatment optimization: higher probability of target attainment of meropenem was achieved with prolonged infusions in obese patients and with continuous infusions in non-obese patients.