Antimicrobial Activity of Ceftaroline Tested against Staphylococcus aureus from Surgical Skin and Skin Structure Infections in US Medical Centers.

BACKGROUND

Ceftaroline fosamil is a novel cephalosporin approved by the United States Food and Drug Administration (US FDA) for treatment of acute bacterial skin and skin structure infection, including those caused by methicillin-resistant Staphylococcus aureus (MRSA). We evaluated the activity of ceftaroline and comparator agents tested against S. aureus isolated from surgical skin and skin structure infections (SSSI).

METHODS

Clinically substantial isolates (one/patient episode) from SSSI were consecutively collected from 64 medical centers in the United States over a 6-y period (2008-2013) and tested for susceptibility by broth microdilution methods against ceftaroline and several comparator agents.

RESULTS

Among 794 strains tested, 50.5% were MRSA. Ceftaroline was active against all methicillin-susceptible Staphylococcus aureus (MSSA; minimal inhibitory concentration [MIC]90, 0.25 mcg/mL) and nearly all MRSA (MIC90, 1 mcg/mL). Against MSSA, ceftaroline was 16-fold more potent than ceftriaxone (MIC90, 4 mcg/mL) and the highest ceftaroline MIC was 0.5 mcg/mL. Among MRSA, 97.5% and 100.0% of strains were inhibited at ≤1 and ≤2 mcg/mL of ceftaroline. Furthermore, 27.4% and 67.5% of MRSA were resistant to clindamycin and levofloxacin, respectively. Daptomycin (MIC50/90, 0.25/0.5 mcg/mL), linezolid (MIC50/90, 1/2 mcg/mL), tigecycline (MIC50/90, 0.06/0.12 mcg/mL) and vancomycin (MIC50/90, 1/2 mcg/mL) were also highly active against S. aureus strains.

CONCLUSIONS

Ceftaroline exhibited potent in vitro activity against S. aureus causing SSSI in a large number of US hospitals, including MRSA. On the basis of this in vitro data, ceftaroline fosamil may represent a valuable option for treatment of surgical SSSI, and should be further evaluated as an agent for surgical prophylaxis that would cover MRSA.