Old antibiotics for multidrug-resistant pathogens: from in vitro activity to clinical outcomes

Area of Science:

• Microbiology
• Infectious Diseases
• Pharmacology

Background:

• Antimicrobial resistance (AMR) poses a significant global health challenge.
• Development of new antimicrobials lags behind the emergence of resistant pathogens.
• Limited treatment options exist for multidrug-resistant (MDR) bacteria.

Purpose of the Study:

• To highlight the increasing reliance on older antimicrobial agents for MDR infections.
• To underscore the scarcity of clinical data on the efficacy of older agents against MDR pathogens.
• To advocate for focused research on evaluating older antimicrobials in MDR infections and complex patient populations.

Main Methods:

• Review of existing literature on older antimicrobial agents and their in vitro activity.
• Analysis of clinical data, where available, for the treatment of MDR pathogens.
• Identification of knowledge gaps concerning pharmacokinetic/pharmacodynamic properties and toxicities of older agents.

Main Results:

• Some older antimicrobials retain potent in vitro activity against highly resistant bacteria.
• Clinical data on the use of older agents for MDR infections are generally limited.
• Unfavorable pharmacokinetic/pharmacodynamic profiles and toxicities can restrict the use of some older agents.

Conclusions:

• Older antimicrobial agents represent a valuable, albeit underutilized, resource in combating MDR pathogens.
• Further clinical investigation is crucial to establish the safety and efficacy of older antimicrobials.
• Research should prioritize evaluating these agents in diverse and complex patient populations, including those with comorbidities.