Breakpoint determination when multiple organisms are tested for effect targets

Some Suggestions from PK/PD Principles to Contain Resistance in the Clinical Setting-Focus on ICU Patients and Gram-Negative Strains

The containment of the phenomenon of resistance towards antimicrobials is a priority, especially in preserving molecules acting against Gram-negative pathogens, which represent the isolates more frequently found in the fragile population of patients admitted to Intensive Care Units. Antimicrobial therapy aims to prevent resistance through several actions, which are collectively known as "antimicrobial stewardship", to be taken together, including the application of pharmacokinetic/pharmacodynamic (PK/PD) principles. PK/PD application has been shown to prevent the emergence of resistance in numerous experimental studies, although a straight translation to the clinical setting is not possible. Individualized antibiotic dosing and duration should be pursued in all patients, and even more especially when treating intensive care unit (ICU) septic patients in whom optimal exposure is both difficult to achieve and necessary. In this review, we report on the available data that support the application of PK/PD parameters to contain the development of resistance and we give some practical suggestions that can help to translate the benefit of PK/PD application to the bedside.

Human-Simulated Antimicrobial Regimens in Animal Models: Transparency and Validation Are Imperative

Animal infection models are invaluable in optimizing antimicrobial dosage in humans. Utilization of human-simulated regimens (HSRs) in animal models helps to evaluate antimicrobial efficacy at clinically achievable drug concentrations. To that end, pharmacokinetic studies in infected animals and confirmation of the HSR pharmacokinetic profile are essential in evaluating observed versus expected drug concentrations. We present and compare two murine meropenem-vaborbactam HSR profiles, their potential impact on bacterial killing, and clinical translatability.