In vitro evaluation of voriconazole against clinical isolates of yeasts, moulds and dermatophytes in comparison with itraconazole, ketoconazole, amphotericin B and griseofulvin

The in vitro activity of voriconazole (UK-109, 496), a new antifungal triaz ole derivative, against 650 clinical isolates of yeasts, moulds and dermato phytes was compared with that of itraconazole, ketoconazole, amphotericin B and griseofulvin. The geometric means of the minimum inhibitory concentrat ions (MICs) of voriconazole were 0.05 mu g ml(-1) against yeasts (n = 187), 0.58 mu g ml(-1) against moulds (n = 260) and 0.08 mu g ml(-1) against der matophytes (n = 203). The overall activity of voriconazole against yeasts a nd moulds was good, being similar to that of itraconazole, ketoconazole and amphotericin B. Voriconazole was highly effective against Aspergillus fumi gatus (mean MIC 0.23 mu g ml(-1)) and other Aspergillus species and showed noteworthy activity (mean MICs 0.08-0.78 mu g ml(-1)) against emerging and less common clinical isolates of opportunistic moulds, such as Alternaria s pp. Cladosporium spp., Acremonium spp., Chrysosporium spp, and Fusarium spp . On the other hand, voriconazole was less active in vitro than the compara tive agents studied against various species of zygomycetes, such as Mucor s pp., Rhizopus spp. and Absidia spp. Voriconazole and the other two azoles, itraconazole and ketoconazole, were more active than griseofulvin in vitro against most dermatophytes tested.