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Polymyxins and their novel derivatives
1Northern Antibiotics Ltd., Eskolantie 1, POB 72, FI-00720 Helsinki, Finland; Division of Clinical Microbiology, Helsinki University Hospital, Haartmaninkatu 3, POB 30, FI-00029 HUSLAB, Helsinki, Finland. martti.vaara@northernantibiotics.com
Current Opinion in Microbiology
|September 28, 2010
Summary
New polymyxin derivatives offer a potential solution to multidrug-resistant Gram-negative infections. These agents show reduced toxicity and altered kidney interactions, addressing key limitations of current polymyxin therapies.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Multidrug-resistant Gram-negative bacteria pose significant therapeutic challenges.
- Polymyxins (polymyxin B, colistin) are last-resort treatments but exhibit nephrotoxicity.
- There is a critical need for safer alternatives to existing polymyxins.
Purpose of the Study:
- To review novel polymyxin derivatives with potentially reduced toxicity.
- To explore structure-function relationships of new polymyxin analogs.
- To discuss acquired resistance mechanisms and their implications.
Main Methods:
- Review of preclinical studies on novel polymyxin derivatives.
- Analysis of structural modifications and their impact on toxicity and efficacy.
- Examination of polymyxin resistance mechanisms.
Main Results:
- Novel polymyxin derivatives exhibit modified cationic charges and altered renal handling.
- These derivatives demonstrate potential for reduced nephrotoxicity compared to parent polymyxins.
- Acquired resistance mechanisms may impair bacterial outer membrane function.
Conclusions:
- Developing less toxic polymyxin derivatives is crucial for treating resistant Gram-negative infections.
- Understanding structure-function relationships guides the design of improved polymyxin agents.
- Emerging resistance necessitates ongoing research into polymyxin derivatives and their mechanisms.
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