1622. The effect of lung surfactant on the in vitro activity of dalbavancin against Staphylococcus aureus and Streptococcus pneumoniae
Session: Poster Abstract Session: Novel Antimicrobial Agents
Saturday, October 20, 2012
Room: SDCC Poster Hall F-H
Posters
  • Poster 1622_IDSA 2012_FINAL.pdf (123.8 kB)
  • Background: Dalbavancin is a long acting intravenous lipoglycopeptide antibiotic with activity against Gram positive organisms that is currently in Phase III clinical studies for acute bacterial skin and skin structure infection.  For potential respiratory infection indication purposes, this study was performed to determine the effect of lung surfactant on the in vitro activity of dalbavancin against S. aureus and S. pneumoniae

    Methods: A total of 5 S. aureus and 5 S. pneumoniae were tested by CLSI broth microdilution (BMD) methods for dalbavancin with and without the addition of 1% and 5% lung surfactant (Survanta® – extract of bovine lung surfactant consisting of 89.3% phospholipids, 7.1% other lipids and 5-10% protein).   Daptomycin was also tested for S. aureus ATCC 29213 and S. pneumoniae ATCC 49619, as a positive control. 

    Results: Dalbavancin MIC results for broth+surfactant in comparison to broth only:

    Species

    1% Surfactant

    5% Surfactant

    S. aureus

    Equivalent MIC for 4 strains                   1 dilution higher MIC for 1 strain

    1 dilution higher MIC for 5 strains

    S. pneumoniae

    Equivalent MIC for 3 strains                   1 dilution higher MIC for 2 strains

    1 dilution higher MIC for 5 strains

    In contrast, daptomycin MICs for S. aureus ATCC 29213 were 5 and 7 dilutions higher with addition of 1% and 5% surfactant, respectively and for S. pneumoniae ATCC 49619 were 3-4 dilutions and 6 dilutions higher with addition of 1% and 5% surfactant respectively.

    Conclusion: The addition of lung surfactant did not have a significant impact on the in vitro susceptibility of S. aureus and S. pneumoniae to dalbavancin as determined by broth microdilution.

    Michael Dunne, MD, Durata Therapeutics, Inc., Morristown, NJ, Laura Koeth, Laboratory Specialists, Inc., Westlake, OH and Anne Windau, MicroTech Laboratories, Westlake, OH

    Disclosures:

    M. Dunne, Durata Therapeutics: Employee, Salary

    L. Koeth, Durata Therapeutics: Research Contractor, Research grant

    A. Windau, None

    Findings in the abstracts are embargoed until 12:01 a.m. PST, Oct. 17th with the exception of research findings presented at the IDWeek press conferences.