In Vitro: Ceftobiprole (Ro 63-9141) has demonstrates activity against important gram-positive bacteria, including S. pneumonia (PRSP), Methicillin-resistant S. aureus (MRSA), and E. faecalis with MIC90 values of 0.25, 2, and 2 mcg/mL, respectively. Ceftobiprole has also demonstrated potent in vitro activity against several clinical isolates of community-associated Methicillin-resistant S. aureus (CA-MRSA), S. aureus (VISA), and S. aureus (VRSA), with a minimum inhibitory concentration (MIC) of 2 mcg/mL. Ceftobiprole is highly active against S. aureus, withMICs ranging from 0.12 to 4 mg/L (only one resistant strain,MIC of 4 mg/L). Furthermore, Ceftobiprole is twice more active on Methicillin-susceptible S. aureus (MSSA) strains with MIC50 and MIC90 of 0.5 mg/L than on MRSA strains with MIC50 and MIC90 of 1 mg/L. Moreover, Panton-Valentine leukocidin (PVL)+MRSA are slightly more susceptible to Ceftobiprole (MIC50 of 0.5 mg/L and MIC90 of 1 mg/L) than PVL-MRSA (MIC50 and MIC90 of 1 mg/L).