In Vitro Activity of Tebipenem (SPR859), Tebipenem-Pivoxil (SPR994) and Meropenem Against a Broad Spectrum of Anaerobic Bacteria Posted on June 11, 2018 at 2:31 pm.Written by Spero Therapeutics View Presentation Post navigation Characterization of the Mechanism of Action of Tebipenem (SPR859) in the Escherichia coli Macromolecular Synthesis AssayAntimicrobial Activity Assessment of Tebipenem (SPR859) against an Isolate Collection Causing Urinary Tract Infections