Novel triazole antifungal agents

The risk of opportunistic infections is greatly increased in patients who a re immunocompromised due to AIDS, cancer chemotherapy and organ or bone mar row transplantation. Candida albicans is often associated with serious syst emic fungal infections, however other Candida species such as Candida kruse i Candida tropicalis and Candida glabrata, as well as Cryptococcus neoforma ns and filamentous fungi such as Aspel-gillus: have also emerged as clinica lly significant fungal pathogens. Two triazole antifungal agents, fluconazo le and itraconazole, were introduced over a decade ago and since then have been used extensively for the prophylaxis and treatment of a variety of fun gal infections. Although both drugs are effective and have their place in t herapy, limitations regarding the utility of these agents do exist. For exa mple, fluconazole is not effective for the prophylaxis or treatment of Aspe rgillus species and has limited activity against C. Krusei and C. glabrata. The use of itraconazole has been limited secondary to concerns regarding u npredictable bioavailability. The rising incidence of fungal infections and the reported-increase of non-albicans candidal infections noted over the p ast two decades highlight the need for new antifungal agents with improved spectra of activity. Several new triazole agents are in various phases of p reclinical and clinical trials and may be available for human use in the ne ar future. Three such agents voriconazole, posaconazole and ravuconazole ar e reviewed and compared with existing agents.