Voriconazole inhibits biofilm formation in different species of the genus Candida

To determine the ability of voriconazole to inhibit the formation of biofilms. A total of 38 blood isolates of Candida spp. (8 Candida albicans, 10 Candida tropicalis, 10 Candida glabrata, 7 Candida parapsilosis sensu stricto and 3 Candida orthopsilosis) and C. albicans ATCC 90028 and ATCC 64548 were assessed. Biofilm formation was quantified using XTT reduction assays. The inhibition of biofilm formation was determined (i) in the presence of 0.06 and 0.25 mg/L voriconazole, and (ii) on surfaces previously coated with 0.06, 0.25, 1, 4 and 16 mg/L voriconazole. Voriconazole reduced biofilm formation under both conditions, the extent depending on the species, isolate and drug concentration. In the presence of 0.25 mg/L, the highest reduction was found for C. parapsilosis (798.6), followed by C. albicans (64.56.3), C. tropicalis (53.313.1) and C. glabrata (23.811.2). This reduction was significant (P0.05) for all isolates tested. After coating the wells with voriconazole, biofilm formation was reduced in all Candida spp. examined, C. albicans being the species with the highest reduction (68.8 with 16 mg/L) and C. parapsilosis complex and C. glabrata the lowest. As voriconazole reduces biofilm formation it may be a good candidate for the prevention of Candida biofilm-related infections although further studies using voriconazole-impregnated catheter tubing or prostheses are required to confirm these results.