CQ-397 and CQ-414: antimicrobial activity and spectrum of two fluoroquinolone---cephalosporin, dual-action compounds with carboxamido bonds.
OBJECTIVE: To evaluate the potential spectrum of activity of two novel dual-action compounds with carboxamido bonds (CQ-397 and CQ-414; Laboratorios Aranda, San Rafael, Mexico) against human pathogens. METHODS: Approximately 800 Gram-positive and Gram-negative aerobic clinical bacteria were tested in vitro using the Mueller-Hinton broth microdilution method of the National Committee of Clinical Laboratory Standards. RESULTS: CQ-397 (cefamandole+enrofloxacin) and CQ-414 (cefamandole+norfloxacin) were equally potent against Enterobacteriaceae (MIC90 range, 0.06--0.5 microg/mL and 0.06--1 microg/mL, respectively). Citrobacter freundii (MIC90, 4 microg/mL) and Providencia spp. (MIC90, >32 microg/mL) exhibited elevated study drug MICs. Enterobacteriaceae resistant to fluoroquinolones generally remained resistant. CQ-397 and CQ-414 were active against Stenotrophomonas maltophilia (MIC90, 4 microg/mL) and oxacillin-susceptible staphylococci (MIC90, 0.25 microg/mL), but not oxacillin-resistant Staphylococcus aureus (MIC90, >32 microg/mL), Staphylococcus epidermidis (MIC90, 8 microg/mL), and enterococci (MIC90s, 8 to >32 microg/mL). There was no difference in the dual-action drug activity (MIC90, 2 microg/mL) between penicillin-susceptible and -resistant pneumococci. Haemophilus influenzae and Moraxella catarrhalis were very susceptible (MIC range, less-than-or-equal0.015--0.06 microg/mL) to both compounds. CONCLUSIONS: The activity of these novel dual-action compounds, formed from the bonding of older antimicrobials, warrants further investigation for potential human and/or animal health use, including toxicology and pharmacokinetics.
Johnson
David M.
DM
Medical Microbiology Division, Department of Pathology, University of Iowa College of Medicine, Iowa City, Iowa, USA.
Jones
Ronald N.
RN