787. Comparative In-Vitro Activity of Nemonoxacin Against Staphylococcus aureus
Session: Poster Abstract Session: Antimicrobial Agents: Novel Agents
Friday, October 9, 2015
Room: Poster Hall
  • IDSA_2015.pdf (720.5 kB)
  • Background: Nemonoxacin is a new investigational quinolone antimicrobial agent with enhanced activity against Gram(+) microorganisms. The aim of the study was  to evaluate the in vitro activity of nemonoxacin against community-acquired and nosocomial isolates of S.aureus isolated in Russia.

    Methods: In total 200 strains of Staphylococcus aureus (100–MRSA, 100–MSSA) isolated from patients with community-acquired and nosocomial infections in different regions of Russia were tested. MICs of antimicrobials were determined using broth microdilution method according to ISO and EUCAST methodology.

    Results: The results of susceptibility testing are summarized in the Table. 
    Antimicrobial MIC50/MIC90/MIC ranges (mg/l)  for MRSA MIC50/MIC90/MIC ranges (mg/l) for MSSA
    Ceftaroline 1/2/0.25-2 0.25/0.25/0.06-0.25
    Ciprofloxacin 32/128/0.25-256 0.25/0.5/0.25-16
    Clindamycin 256/512/0.06-512 0.06/0.06/0.06-512
    Levofloxacin 4/16/0.06-16 0.125/0.25/0.06-4
    Linezolid 2/4/0.125-4 2/2/0.5-2
    Nemonoxacin 0.5/0.5/0.03-2 0.03/0.06/0.014-0.25
    Tetracycline 0.5/64/0.125-256 0.125/4/0.125-32
    Trimethoprim/Sulfamethoxazole 0.06/0.125/0.03-64 0.06/0.06/0.03-0.5
    Vancomycin 1/1/0.125-2 1/1/0.5-1

    Conclusion: Nemonoxacin was substantially more active in vitro than ciprofloxacin and levofloxacin against tested S.aureus strains. At the same time, activity of Nemonoxacin against MRSA was notably lower than against MSSA – MIC50/90 0.5/05 mg/l versus 0.03/0.06 mg/l, respectively. The activity of Nemonoxacin against ciprofloxacin-resistant S.aureus strains was also substantially lower than against ciprofloxacin-susceptible strains - MIC50/90 0.5/05 mg/l and 0.03/0.06 mg/l, respectively. Overall nemonoxacin was one of the most in-vitro active antimicrobials tested.

    Andrey Dekhnich, MD, MSc, PhD1, Roman Kozlov, MD, MSc, PhD1, Marina Sukhorukova, MD, MSc, PhD1, Mikhail Edelstein, PhD1 and Mikhail Samsonov, MD, MSc, PhD2, (1)Institute of Antimicrobial Chemotherapy, Smolensk, Russia, (2)R-Pharm, Moscow, Russia


    A. Dekhnich, None

    R. Kozlov, None

    M. Sukhorukova, None

    M. Edelstein, None

    M. Samsonov, None

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 7th with the exception of research findings presented at the IDWeek press conferences.