In vitro activity of three new triazoles and one echinocandin against Candida bloodstream isolates from cancer patients

The in vitro activities of voriconazole, posaconazole, ravuconazole and micafungin were compared with those of fluconazole, itraconazole, ketoconazole, flucytosine and amphotericin B against 164 candidaemia isolates recovered from cancer patients in two Canadian centres. The MIC(50) results for ravuconazole, voriconazole, posaconazole and micafungin were 0.01, 0.03, 0.12 and 0.25 mg/L, respectively. The new antifungal agents showed substantial activity against isolates demonstrating in vitro resistance to fluconazole and itraconazole. These results suggest that the newer antifungal agents possess promising activity against invasive Candida isolates, particularly against those with reduced susceptibility to fluconazole and itraconazole.