title: Activity of ABT-773 against Mycobacterium avium complex in the beige mouse model.
abstract: ABT-773, a new ketolide antimicrobial agent, was evaluated in comparison to clarithromycin (CLA) in vitro against Mycobacterium avium complex (MAC) and in a beige mouse model of disseminated MAC infection. The MICs at which 50 and 90% of the isolates tested were inhibited were 2 and 4 microg/ml, respectively, for CLA and 8 and 16 microg/ml, respectively, for ABT-773. Eight CLA-resistant isolates were found to be resistant to ABT-773 (MICs > 64 microg/ml). In the in vivo study mice were treated with ABT-773 (50, 100, and 200 mg/kg of body weight) or CLA (200 mg/kg). Both ABT-773 (100 and 200 mg/kg) and CLA significantly decreased the viable cell counts in spleens and lungs. ABT-773 (200 mg/kg) and CLA had similar activities in lungs, but the former was more active in spleens.
authors.affiliation: Veterans Affairs Medical Center and State University of New York, Upstate Medical University, Syracuse, New York 12310, USA. Michael.Cynamon@Med.VA.Gov
authors.forename: M H
authors.initials: MH
authors.lastname: Cynamon
authors.forename: J L
authors.initials: JL
authors.lastname: Carter
authors.forename: C M
authors.initials: CM
authors.lastname: Shoen
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002452:Cell Count; D017291:Clarithromycin / Q000627:therapeutic use*; D004917:Erythromycin / Q000031:analogs & derivatives* / Q000494:pharmacology; D048628:Ketolides; D008168:Lung / Q000382:microbiology; D051379:Mice; D008826:Microbial Sensitivity Tests; D015269:Mycobacterium avium Complex; D015270:Mycobacterium avium-intracellulare Infection / Q000188:drug therapy* / Q000382:microbiology; D013154:Spleen / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D048628:Ketolides; D004917:Erythromycin; D017291:Clarithromycin; C405499:cethromycin