Activity of Tigecycline (GAR-936) against Acinetobacter baumannii Strains, Including Those Resistant to Imipenem

Abstract

ABSTRACT We determined the in vitro activities of tigecycline and imipenem against 49 isolates of Acinetobacter baumannii , including those resistant to imipenem. The MIC at which 50% of the isolates were inhibited (MIC 50 ) and the MIC 90 for tigecycline and imipenem were 2 and 2 mg/liter and 32 and 128 mg/liter, respectively, with 92 and 20%, respectively, of the strains being susceptible. Tigecycline did not show bactericidal activity in the time-kill studies ( n = 9 strains). Imipenem showed bactericidal activity against seven out of nine strains. These in vitro results show that tigecycline has good in vitro bacteriostatic activity against A. baumannii , including strains resistant to imipenem.