In VitroAntimicrobial Activity of Razupenem (SMP-601, PTZ601) against Anaerobic Bacteria

Abstract

ABSTRACTWe evaluated thein vitroantianaerobic activity of razupenem (SMP-601, PTZ601), a new parenterally administered carbapenem, against 70 reference strains and 323 clinical isolates. Razupenem exhibited broad-spectrum activity against anaerobes, inhibiting most of the reference strains when used at a concentration of ≤1 μg/ml. Furthermore, it exhibited strong activity, comparable to those of other carbapenems (meropenem and doripenem), against clinically isolated non-fragilis Bacteroidesspp. (MIC90s of 2 μg/ml), with MIC90values of 0.06, 0.03, and 0.5 μg/ml againstPrevotellaspp.,Porphyromonasspp., andFusobacteriumspp., respectively. Clinical isolates of anaerobic Gram-positive cocci,Eggerthellaspp., andClostridiumspp. were highly susceptible to razupenem (MIC90s, 0.03 to 1 μg/ml).