Antimicrobial activity of ceftobiprole and comparator agents when tested against Gram-positive and -negative organisms collected across China (2016-2018)

Abstract

Background: Ceftobiprole is a fifth-generation cephalosporin which has been reported on the antibacterial spectrum when against bacteria collected from other countries except China. This study evaluated the in vitro activity of ceftobiprole in comparison with other comparators against clinically significant isolates collected across from China. Results: Susceptibility testing of ceftobiprole and comparators against 1163 clinically isolated Gram-positive and Gram-negative bacteria was performed with broth micro dilution method following the CLSI guidelines. All 110 S. aureus were susceptible to ceftobiprole with MIC50/90 of 1/2 mg/L for MRSA and 0.5/1 mg/L for MSSA. For Coagulase-negative staphylococci (CNS), MIC50/90 of ceftobiprole for MRCNS and MSCNS was 1/2 mg/L and 0.25/0.5 mg/L. Ceftobiprole demonstrated good potency against E. faecalis (MIC50/90 of 0.5/1 mg/L) but bad against E. faecium (MIC50/90 of >32/>32 mg/L). Ceftobiprole demonstrated potent activity against all 39 β-hemolytic Streptococcus with MIC50/90 ≤0.015/≤0.015-2 mg/L and 110 of PSSP with 98.2% susceptibility. Ceftobiprole inhibited all isolates of H. influenzae and M. catarrhalis at ≤ 1 mg/L. 91.8% and 98.2% of the ESBL-negative E. coli and K. pneumoniae were susceptible to ceftobiprole, but most of the ESBL-positive or carbapenem-resistant strains were also resistant to ceftobiprole. Ceftobiprole inhibited 84.2% of carbapenem-susceptible P. aeruginosa and 94.1% of carbapenem-susceptible A. baumannii at ≤8 mg/L, but only 52.6% of carbapenem-resistant P. aeruginosa and 5.3% of carbapenem-resistant A. baumannii. Conclusion: Ceftobiprole was active in vitro against a broad range of clinically relevant contemporary Gram-positive and Gram-negative bacterial isolates.