Antimicrobial Activity Evaluation of Tebipenem (SPR859), an Orally Available Carbapenem, against a Global Set of Enterobacteriaceae Isolates, Including a Challenge Set of Organisms.

The antimicrobial activity of tebipenem and other carbapenem agents were tested against a set of recent clinical isolates responsible for urinary tract infection (UTI), as well as against a challenge set. Isolates were tested by reference broth microdilution and included (101 isolates), (208 isolates), and (103 isolates) species. Within each species tested, tebipenem showed equivalent MIC values to those of meropenem ( MIC, ≤0.015/0.03 mg/liter; MIC, 0.03/0.06 mg/liter; and MIC, 0.06/0.12 mg/liter) and consistently displayed MIC values 8-fold lower than imipenem. Tebipenem and meropenem (MIC, 0.03 mg/liter) showed equivalent MIC results against wild-type, AmpC-, and/or extended-spectrum β-lactamase (ESBL)-producing isolates. Tebipenem also displayed MIC values 4- to 8-fold lower than imipenem against the challenge set. All carbapenem agents were less active (MIC, ≥8 mg/liter) against isolates carrying carbapenemase genes. These data confirm the activity of the orally available agent tebipenem against prevalent UTI species, including those producing ESBLs and/or plasmid AmpC enzymes.