A Multi-Site Evaluation of Isavuconazole on the Sensititre YeastOne Test Plate with the Frozen Reference CLSI M27-A3 and ISO 16256 Micro Broth Dilution Methods for Antifungal Susceptibility Testing A Multi-Site Evaluation of Isavuconazole on the Sensititr

N. M. Holliday1 , C. C. Knapp1 , S. B. Killian1 , D. N. Zollos1 , E. Scopes2 , M. A. Ghannoum3 , R. N. Jones4 , J. M. Streit4 , M. Castanheira4 , R. R. Dietrich4 , S. A. Messer4 , K. Lagrou5 , S. Patteet5

Author address: 

1Thermo Fisher Scientific, Oakwood Village, OH, 2Thermo Fisher Scientific, Basingstoke, United Kingdom, 3Case Western Reserve Univ., Cleveland, OH, 4 JMI Lab., North Liberty, IA, 5UZ Leuven, Leuven, Belgium


Background: Isavuconazole (Astellas Pharma US, Inc., Northbrook, IL) is a triazole antifungal that is currently approved for use in the treatment of invasive mucormycosis and aspergillosis. A multi-site evaluation was undertaken to determine the performance of the Thermo Scientific™ Sensititre® YeastOne® susceptibility system (Thermo Fisher Scientific, Cleveland, OH) with Isavuconazole (ISA) compared to the CLSI M27 and ISO16256 (2012)(E) Broth Microdilution Methods (BMD).Materials and Methods: 400 clinical (100 per site) and 100 challenge strains along with 10 reproducibility isolates of Candida spp. were tested at 4 sites comparing the performance of ISA on the Sensititre YeastOne plate with CLSI and ISO BMD. The range tested for ISA was 0.004-8ug/ml. CLSI quality control (QC) organisms were tested daily and were within the CLSI expected QC ranges. Results: Clinical isolate comparisons of the Sensititre YeastOne plate to the CLSI and ISO BMD resulted in 99% and 92% essential agreement (EA) +/- 2 log2 dilutions. Challenge isolates resulted in 99% and 89% EA +/- 2 log2 dilutions. YeastOne modal reproducibility MICs +/- 2 fold dilutions between sites for ISA resulted in 98.6% agreement at 24 hours. Conclusions: This evaluation indicates that the Sensititre YeastOne plate with ISA is equivalent to the CLSI and ISO BMD and is a potential method for susceptibility testing of ISA.

abstract No: 


Full conference title: 

ASM Microbe 2016
    • ASM microbe 1st (2016)