Article

Echinocandins: the newest class of antifungals.

Lloyd L. Gregory School of Pharmacy, Palm Beach Atlantic University, West Palm Beach, FL, USA.
Annals of Pharmacotherapy (impact factor: 2.13). 10/2009; 43(10):1647-57. DOI:10.1345/aph.1M237 pp.1647-57
Source: PubMed

ABSTRACT To review the mechanism of action, antifungal spectrum of activity, pharmacodynamics, pharmacokinetics, clinical efficacy, and safety of the echinocandins.
A MEDLINE search (1982-May 2009) was conducted for articles published in the English language using the key words caspofungin, micafungin, anidulafungin, and echinocandins.
Medicinal chemistry, in vitro, and animal studies, as well as human trials were reviewed for information on the pharmacodynamics, pharmacokinetics, efficacy, and safety of each echinocandin. Clinical trials were reviewed and included to compare and contrast the available echinocandins.
Three echinocandin antifungal agents are currently approved for use in the US: caspofungin, micafungin, and anidulafungin. The echinocandins have a unique mechanism of action, inhibiting beta-(1,3)-D-glucan synthase, an enzyme that is necessary for the synthesis of an essential component of the cell wall of several fungi. The echinocandins display fungistatic activity against Aspergillus spp. and fungicidal activity against most Candida spp., including strains that are fluconazole-resistant. The echinocandins have been shown to be efficacious for the treatment of esophageal candidiasis, candidemia, and invasive candidiasis. In addition, caspofungin has demonstrated efficacy as empiric treatment of febrile neutropenia and salvage therapy for the treatment of invasive aspergillosis, and it is the only echinocandin approved for use in pediatric patients. Micafungin is the only echinocandin approved for use as prophylaxis against Candida infections in patients undergoing hematopoietic stem cell transplantation. Overall, resistance to echinocandins is still rare, and all agents are well tolerated, with similar adverse effect profiles and few drug-drug interactions.
Echinocandins, the newest addition to the arsenal of antifungals, offer potential advantages over other classes of agents. Clinicians should assess their distinguishing characteristics, including route of metabolism, drug interaction profile, and approved indications for use, when determining which agent to include on a formulary.

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Keywords

antifungal spectrum
 
available echinocandins
 
Candida infections
 
cell wall
 
clinical efficacy
 
distinguishing characteristics
 
drug interaction profile
 
drug-drug interactions
 
echinocandin antifungal agents
 
Echinocandins
 
echinocandins display fungistatic activity
 
inhibiting beta-(1,3)-D-glucan synthase
 
invasive aspergillosis
 
key words caspofungin
 
Medicinal chemistry
 
offer potential advantages
 
patients undergoing hematopoietic
 
pediatric patients
 
similar adverse effect profiles
 
unique mechanism
 

Allana J Sucher