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Published on: April 18, 2019

Polymyxin B for the treatment of multidrug-resistant pathogens: a critical review

Alexandre Prehn Zavascki1, Luciano Zubaran Goldani, Jian Li

  • 1Infectious Diseases Service, Hospital São Lucas da Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.

The Journal of Antimicrobial Chemotherapy
|September 20, 2007
PubMed

Insights

Polymyxin B shows rapid activity against multidrug-resistant Gram-negative bacteria, offering a last-resort treatment option. Further clinical trials are needed to establish optimal dosing and confirm efficacy for these difficult-to-treat infections.

Area of Science:

  • Pharmacology
  • Infectious Diseases
  • Microbiology

Background:

  • Polymyxins are crucial last-resort antibiotics for multidrug-resistant (MDR) Gram-negative bacterial infections.
  • The limited antibiotic development pipeline necessitates a re-evaluation of existing drugs like polymyxins.

Purpose of the Study:

  • To review available microbiological, pharmacokinetic, pharmacodynamic, and clinical data for polymyxin B.
  • To assess the current evidence supporting polymyxin B's use against MDR Gram-negative pathogens.

Main Methods:

  • Literature review of microbiological, pharmacokinetic, pharmacodynamic, and clinical studies on polymyxin B.
  • Analysis of in vitro activity against key MDR Gram-negative bacteria (e.g., Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae).

Main Results:

  • Polymyxin B exhibits rapid in vitro bactericidal activity against major MDR Gram-negative bacteria.
  • Acquired resistance to polymyxin B remains rare in these pathogens.
  • Recent studies show good clinical outcomes, but require further validation due to design limitations.

Conclusions:

  • Polymyxin B is a valuable agent for MDR Gram-negative infections, with rare resistance.
  • Optimal dosage regimens and definitive clinical evidence are still lacking.
  • Urgent need for clinical pharmacokinetic, pharmacodynamic, and toxicodynamic studies to guide optimal polymyxin use.

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