Evaluation of the in vitro activity of isavuconazole and comparator voriconazole against 2635 contemporary clinical Candida and Aspergillus isolates

Isavuconazole displayed broad in vitro activity, similar to that of voriconazole. Up to 15% of C. glabrata, C. tropicalis and A. fumigatus isolates were non-wt, reflecting increased resistance at a reference centre and technical issues. Significant CYP51A alterations were reliably detected applying the isavuconazole breakpoint.