Microdialysis for in vivo pharmacokinetic/pharmacodynamic characterization of anti-infective drugs

Area of Science:

• Pharmacology and Microbiology
• Drug Delivery and Pharmacokinetics

Background:

• Inadequate antibiotic tissue penetration is a significant cause of treatment failure and the development of bacterial resistance.
• Current methods for assessing antibiotic tissue distribution, like biopsies, have limitations in accurately reflecting drug concentrations at the target site.
• Pharmacokinetic evaluations should prioritize tissue concentrations over serum concentrations for a more accurate understanding of antibiotic efficacy.

Purpose of the Study:

• To highlight the importance of tissue pharmacokinetic evaluation for antibiotics.
• To introduce and advocate for microdialysis as a superior technique for measuring antibiotic distribution in tissues.
• To explore the potential of microdialysis in defining surrogate markers for antibiotic efficiency in drug development.

Main Methods:

• Utilized microdialysis, a semi-invasive, catheter-based sampling technique, for in vivo measurement of antibiotic pharmacokinetics within tissues.
• Compared microdialysis to traditional methods like tissue biopsies, noting the former's improved accuracy and target site access.

Main Results:

• Microdialysis provides selective access to the target site for most anti-infective drugs.
• This technique meets regulatory requirements for pharmacokinetic distribution studies.
• Microdialysis demonstrates potential as a future reference standard for tissue distribution studies.

Conclusions:

• Microdialysis is a valuable tool for accurate in vivo assessment of antibiotic tissue pharmacokinetics.
• The technique's ability to reflect drug concentrations at the site of action is critical for optimizing antibiotic therapy.
• Microdialysis may play a key role in developing new surrogate markers to predict antibiotic efficacy during drug development.