Assessment of BMS284756 MIC and 5-microg disk diffusion quality control studies tested against seven American type culture collection strains.

BMS284756 is a novel des-fluoro(6)-quinolone with antimicrobial activity similar to recently developed fluorinated quinolones. The purpose of this investigation was to determine the appropriate disk diffusion and MIC quality control (QC) ranges for BMS284756 when used against commonly tested QC strains (M23-A2). The BMS284756 5-microg disk content was tested against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Hemophilus influenzae ATCC 49247, Streptococcus pneumoniae ATCC 49619 and Staphylococcus aureus ATCC 25923. In addition, Enterococcus faecalis ATCC 29212 and S. aureus ATCC 29213 were evaluated by the broth microdilution method. Seven laboratories tested 2 disk lots on 3 agar media or 3-4 broth lots over a 10 day period. A total of 420 zone diameter values and 210 or 280 MIC values per organism were generated. The following disk diffusion and MIC QC ranges were suggested for BMS284756 and the seven QC strains: E. coli ATCC 25922 (28-35 mm/0.004-0.016 microg/mL), E. faecalis ATCC 29212 (0.03-0.25 microg/mL), S. aureus ATCC 25923 (30-36 mm), S. aureus ATCC 29213 (0.004-0.016 microg/mL), P. aeruginosa ATCC 27853 (19-25 mm/0.5-2 microg/mL), H. influenzae ATCC 49247 (33-41 mm/0.002-0.008 microg/mL), S. pneumoniae ATCC (26-33 mm/0.016-0.06 microg/mL). The proportion of participant results observed within the proposed ranges was 97.4-98.8% and 94.6-100% for the disk diffusion and MIC tests, respectively.