25 – – ≤0.5c – – ≤0.25 >0.25 Streptococcus agalactiae ≤0.03 – – ≤0.5     d d Streptococcus pyogenes ≤0.015 – – ≤0.5 – – d d Haemophilus influenzae ≤0.12 – – ≤0.5 – – ≤0.03 >0.03 Enterobacteriaceae ≤0.5 1 ≥2 ≤0.5 1 ≥2 ≤0.5 >0.5 I intermediate, R resistant, S susceptible aIntermediate and resistant results not defined by the FDA for some pathogens bIncludes methicillin-resistant S. aureus cNon-meningitis dβ-Lactam susceptibility of Streptococcus groups A, B, C and G is inferred from the penicillin susceptibility Results from the 2010 Assessing Worldwide Antimicrobial Resistance Evaluation (AWARE) program (Table 2) [36–42], a global Obeticholic ceftaroline surveillance study, showed that ceftaroline is highly active against S. aureus and MRSA among

isolates collected from medical centers in nine United States census

regions [36]. These high rates of S. aureus susceptibility were independent of patient age group [36]. Among respiratory pathogens, 98.7% of S. pneumoniae strains were inhibited by 0.25 μg/mL or less of ceftaroline, exhibiting potency 16 times Daporinad research buy greater than that of ceftriaxone MK-1775 [37]. During 2008–2010, there was sustained potency and activity against MRSA and MDRSP [defined as a S. pneumoniae isolate with resistance to at least two of the following antimicrobial agents: penicillin (≥8 μg/mL), ceftriaxone, erythromycin, tetracycline, levofloxacin, and trimethoprim–sulfamethoxazole) and the frequency of non-susceptibility of respiratory pathogens to ceftaroline did not vary significantly [37, 38]. Geographic differences in activity among staphylococci, streptococci, Haemophilus spp., and Moraxella catarrhalis were minimal [39]. Susceptibility patterns to ceftaroline among MRSA isolates from Europe, South Sinomenine Africa and the Asia–Pacific

region were lower than those seen in the USA, while consistently high rates of susceptibility to ceftaroline by methicillin-susceptible S. aureus, S. pneumoniae, Haemophilus influenzae and M. catarrhalis were maintained across all these regions [40–42]. Ongoing surveillance will be critical to determine whether resistant strains emerge from selective pressure elicited by more widespread use of ceftaroline. High rates of intermediate susceptibility of S. aureus to ceftaroline have already been noted in vitro among isolates from a surveillance program in China; 36.2% of the 315 isolates tested had an MIC above 1 μg/mL, although the highest MIC documented was 2 μg/mL [43]. Table 2 Summary of ceftaroline activity tested against bacterial isolates causing skin and soft tissue infections and community-acquired pneumonia, by region (AWARE Surveillance, 2010) [36-42] Organism MSSA MRSA GAS GBS PNEUM PRSP H. flu E. coli United States No. isolates [Ref] 1,072 [36] 1,071 [38]a 422 [39] 576 [39] 3,329 [37]a 1,198 [38] 1,545 [37]a 657 [39] MIC 50 0.25 0.5 NS NS 0.015 0.12-0.25 ≤0.008 ≤0.06-0.12 MIC 90 0.25 1 ≤0.008-015 ≤0.015-0.03 0.12 0.25-0.5 0.015 NS % susceptibleb 100/100 98.4/98.4 97.8-100c 80.9-93.1c 98.7c NS 99.