Vol.55 No.S-1 October 2007

In vivo antibacterial activity of garenoxacin

Yoshiko Fukuda, Masahiro Takahata, Yoko Sugiura, Masatoshi Nakatani, Yuko Shinmura, Harumi Hisada, Takashi Komeno, Tomoko Kamiyama, Junichi Mitsuyama and Yozo Todo

Research Laboratories, Toyama Chemical Co. Ltd., 2-4-1 Shimookui, Toyama, Japan

Abstract

In vivo antibacterial activity of garenoxacin(garenoxacin mesilate hydrate: GRNX) on various experimental infections was evaluated.
1. In systemic infection caused by methicillin-resistant Staphylococcus aureus(MRSA) in mice, the 50% effective dose(ED₅₀) of GRNX was 0.00593 mg/mouse, and was lower than that of levofloxacin(LVFX) and gatifloxacin(GFLX). Against penicillin-resistant Streptococcus pneumoniae(PRSP), the ED₅₀ of GRNX was 0.555 mg/mouse, lower than that of LVFX and similar to that of GFLX. The efficacy of GRNX on both Escherichia coli and Pseudomonas aeruginosa infections was similar to that of LVFX and GFLX.
2. In pneumonia caused by PRSP in mice, the viable cell counts in lung after treatment with GRNX was <2.68 Log of CFU/lung, less than that with LVFX and GFLX.
3. In pneumonia caused by Mycoplasma pneumoniae in hamsters, GRNX showed better efficacy than LVFX and clarithromycin(CAM).
4. In pneumonia caused by Chlamydophila pneumoniae in mice, the ED₅₀ of GRNX was 0.0286 mg/mouse, lower than that of LVFX and azithromycin(AZM).
5. In pneumonia caused by Legionella pneumophila in guinea pigs, the viable cell counts after treatment of GRNX was 2.84 Log of CFU/lung, lower than that of ciprofloxacin(CPFX) and CAM, and similar to that of rifampicin.

Key word

garenoxacin, in vivo, antibacterial activity

Received

April 27, 2007

Accepted

July 6, 2007

Jpn. J. Chemother. 55 (S-1): 21-27, 2007