title: Update of the telavancin activity in vitro tested against a worldwide collection of Gram-positive clinical isolates (2013), when applying the revised susceptibility testing method.
abstract: A revised broth microdilution susceptibility testing method for telavancin was approved by the Food and Drug Administration (FDA). Telavancin activity was assessed against Gram-positive pathogens collected worldwide (2013) using the revised method. A total of 12,346 isolates from 90 sites were included as part of the Telavancin International Surveillance Program for the Americas, Europe, and Asia-Pacific. Telavancin had MIC50 and MIC90 values of 0.03 and 0.06 μg/mL, respectively, against staphylococci, regardless of methicillin susceptibility, and inhibited all Staphylococcus aureus at ≤0.12 μg/mL (revised FDA breakpoint). Telavancin was 8-fold more active than daptomycin (MIC50/90, 0.25/0.5 μg/mL) and 16- to 32-fold more active than vancomycin (MIC50/90, 1/1 μg/mL) and linezolid (MIC50/90, 1/1 μg/mL) against methicillin-resistant S. aureus. All 692 vancomycin-susceptible Enterococcus faecalis were inhibited by telavancin (MIC50/90, 0.12/0.12 μg/mL) at ≤0.25 μg/mL (FDA breakpoint), except for 1 strain (MIC, 0.5 μg/mL). All Enterococcus faecium and E. faecalis with telavancin MIC values of ≥0.5 and ≥1 μg/mL, respectively, had a VanA phenotype. A comparison data analysis based on the MIC90 demonstrated that telavancin was at least 8-fold more potent than comparators against vancomycin-susceptible enterococci. Streptococci showed telavancin MIC50 values of ≤0.015 μg/mL, except for Streptococcus agalactiae (MIC50, 0.03 μg/mL). These in vitro results obtained by the recently approved susceptibility testing method establish a new benchmark of telavancin activity worldwide.
authors.affiliation: JMI Laboratories, North Liberty, IA, USA. Electronic address: rodrigo-mendes@jmilabs.com.
authors.forename: Rodrigo E
authors.initials: RE
authors.lastname: Mendes
authors.affiliation: JMI Laboratories, North Liberty, IA, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Farrell
authors.affiliation: JMI Laboratories, North Liberty, IA, USA.
authors.forename: Helio S
authors.initials: HS
authors.lastname: Sader
authors.affiliation: JMI Laboratories, North Liberty, IA, USA.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Streit
authors.affiliation: JMI Laboratories, North Liberty, IA, USA.
authors.forename: Ronald N
authors.initials: RN
authors.lastname: Jones
mesh_terms: D000569:Americas; D000617:Aminoglycosides / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001208:Asia; D005060:Europe; D014943:Global Health; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D000077427:Lipoglycopeptides; D008826:Microbial Sensitivity Tests; D014481:United States
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D000077427:Lipoglycopeptides; C487637:telavancin
keywords: Broth microdilution; Lipoglycopeptide; Polysorbate-80; Susceptibility