Efficacy of Omadacycline against Multidrug-Resistant Enterococcus faecium Strains in a Mouse Peritonitis Model

Omadacycline (OMC) showed better in vitro potency than daptomycin (DAP) or vancomycin (VAN) against Van^r, Amp^r, DAP-nonsusceptible, linezolid-resistant, cfr(B)⁺ Enterococcus faecium strains. In a mouse peritonitis model, OMC also showed significantly better animal survival during the study and at its end than DAP or VAN with these E. faecium strains. However, OMC, DAP, and VAN showed comparable in vitro and in vivo efficacies against a non-vancomycin-resistant, tetracycline-resistant, DAP-susceptible E. faecium strain.