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

Abstract

Abstract

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 (MIC_50/90, 0.25/0.5 mcg/mL), linezolid (MIC_50/90, 1/2 mcg/mL), tigecycline (MIC_50/90, 0.06/0.12 mcg/mL) and vancomycin (MIC_50/90, 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.