Antifungal activity of nikkomycin Z against Candida auris

Abstract Background Nikkomycin Z is a competitive inhibitor of chitin synthase—an enzyme needed for synthesis of the fungal cell wall. Nikkomycin Z shows promise as a treatment for coccidioidomycoses and mixed activity has been described against other fungi and yeast. To our knowledge, it has not previously been tested against the emerging fungal pathogen Candida auris. Objectives To determine the in vitro activity of nikkomycin Z against C. auris. Methods Nikkomycin Z was tested by broth microdilution against a panel of 100 isolates of genetically diverse C. auris from around the world. Results Nikkomycin Z showed mixed activity against the tested isolates, with an MIC range of 0.125 to >64 mg/L. The MIC50 and MIC90 were 2 and 32 mg/L, respectively. Conclusions These findings suggest nikkomycin Z has in vitro activity against some, but not all isolates of C. auris.