In vitro activities of posaconazole (Sch 56592) compared with those of itraconazole and fluconazole against 3,685 clinical isolates of Candida spp. and Cryptococcus neoformans

Posaconazole is a new investigational triazole with broad-spectrum antifung al activity. The in vitro activities of posaconazole were compared with tho se of itraconazole and fluconazole against 3,685 isolates of Candida spp. ( 3,312 isolates) and C. neoformans (373 isolates) obtained from over 70 diff erent medical centers worldwide. The MICs of the antifungal drugs were dete rmined by broth microdilution tests performed according to the National Com mittee for Clinical Laboratory Standards method using RPMI 1640 as the test medium. Posaconazole was very active against all Candida spp. (MIC at whic h 90% of the isolates were inhibited [MIC90], 0.5 mug/ml; 97% of MICs were less than or equal to1 mug/ml) and C. neoformans (MIC90, 0.5 mug/ml; 100% o f MICs were less than or equal to1 mug/ml). Candida albicans was the most s usceptible species of Candida (MIC90, 0.06 mug/ml), and Candida glabrata wa s the least susceptible (MIC90, 4 mug/ml). Posaconazole was more active tha n itraconazole and fluconazole against all Candida spp. and C. neoformans. These results provide further evidence for the spectrum and potency of posa conazole against a large and geographically diverse collection of clinicall y important fungal pathogens.