In Vitro Activity of Sulopenem, an Oral Penem, against Urinary Isolates of Escherichia coli

The in vitro activity of sulopenem was assessed against a collection from 2014 to 2016 of 539 urinary isolates of Escherichia coli from Canadian patients by using CLSI-defined broth microdilution methodology. A concentration of sulopenem 0.03 mu g/ml inhibited both 50% (MIC50) and 90% (MIC90) of isolates tested; sulopenem MICs ranged from 0.015 to 0.25 mu g/ml. The in vitro activity of sulopenem was unaffected by nonsusceptibility to trimethoprim-sulfamethoxazole and/or ciprofloxacin, multidrug-resistant phenotypes, extended-spectrum beta-lactamases, or AmpC beta-lactamases.