Article

In Vitro Activity of a New Oral Glucan Synthase Inhibitor (MK-3118) Tested Against Aspergillus spp. by CLSI and EUCAST Broth Microdilution Methods.

JMI Laboratories, North Liberty, IA 52317, USA.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.45). 12/2012; DOI: 10.1128/AAC.01588-12
Source: PubMed

ABSTRACT MK-3118, a glucan synthase inhibitor derived from enfumafungin, and comparator agents were tested against 71 Aspergillus spp., including itraconazole-resistant strains (MIC, ≥4 μg/ml), using CLSI and EUCAST reference broth microdilution methods. CLSI MEC/MIC(90) values (μg/ml) for MK-3118, amphotericin B, and caspofungin, respectively, were: Aspergillus flavus species complex (SC), 0.12, 2, 0.03; A. fumigatus SC, 0.25, 2, 0.06; A. terreus SC, 0.12, 2, 0.06 and A. niger SC, 0.06, 1, 0.03. Essential agreement between CLSI and EUCAST (±2 log(2) dilution steps) was 94.3%. MK-3118 was determined to be a potent agent regardless of the in vitro method applied, with excellent activity against contemporary wild type and itraconazole-resistant strains of Aspergillus spp.

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