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The renaissance of polymyxins

B Kadar1, B Kocsis, K Nagy

  • 1Institute of Medical Microbiology, Semmelweis University, Budapest, Hungary. szabo.dora@med.semmelweis-univ.hu

Current Medicinal Chemistry
|July 31, 2013
PubMed

Insights

Polymyxins, effective against Gram-negative bacteria, are being re-evaluated due to rising drug resistance. This review covers classic and novel polymyxins, exploring their mechanisms and future therapeutic potential.

Area of Science:

  • Microbiology
  • Pharmacology
  • Infectious Diseases

Background:

  • Polymyxins are polypeptide antibiotics targeting Gram-negative bacteria by damaging cell membranes.
  • Nephro- and neurotoxicity historically limited polymyxin use.
  • The rise of multidrug-resistant Gram-negative bacteria has prompted their reintroduction.

Purpose of the Study:

  • To provide a comprehensive overview of polymyxins.
  • To discuss their history, latest developments, and therapeutic potential.

Main Methods:

  • Literature review of polymyxin antibiotics.
  • Analysis of antimicrobial effects, pharmacodynamics, and pharmacokinetics.
  • Highlighting classic and novel polymyxin agents.

Main Results:

  • Polymyxins exhibit membrane-damaging effects via lipopolysaccharide binding.
  • Classic polymyxins include B and E; non-classic agents are M, S, and T.
  • Novel derivatives like NAB739, NAB740, NAB741, and NAB7061 show future promise.

Conclusions:

  • Polymyxins remain crucial for treating multidrug-resistant Gram-negative infections.
  • Ongoing research into novel derivatives aims to improve efficacy and reduce toxicity.

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