Vol.53 No.S-1 July 2005

In vitro and in vivo antibacterial activity of DRPM, a new carbapenem

Masakatsu Tsuji, Nobuhiko Furuya, Tetsuya Matsumoto, Yoshikazu Ishii, Akira Ohno, Kazuhiro Tateda, Shuichi Miyazaki and Keizo Yamaguchi

Department of Microbiology, Toho University School of Medicine,
5-12-16 Omori-nishi, Ota-ku, Tokyo, Japan

Abstract

We compared the in vitro and in vivo antibacterial activity of DRPM (formerly S-4661), a new 1β-methylcarbapenem, with that of imipenem, panipenem, meropenem, biapenem, cefpirome, ceftazidime, and cefotaxime. DRPM was highly active against methicillin-susceptible staphylococci, penicillin-resistant S. pneumoniae and members of the family Enterobacteriaceae such as Escherichia coli and Enterobacter cloacae, with a MIC at which 90% of tested strains were inhibited (MIC₉₀) to 1 μg/mL or less. Against imipenem-, ceftazidime-, ciprofloxacin-, and gentamicin-resistant P. aeruginosa, DRPM was the most active among tested agents. The in vivo efficacy of DRPM against experimentally induced infection in mice caused by gram-positive and gram-negative bacteria, including penicillin-resistant Streptococcus pneumoniae and β-lactamase producing H. influenzae was similar to that of imipenem-cilastatin and meropenem-cilastatin. We conclude that DRPM is a promising new carbapenem for treating infections caused by gram-positive and negative bacteria, including penicillin-resistant S. pneumoniae and drug-resistant P. aeruginosa.

Key word

doripenem, antibacterial activity, carbapenem, animal model, pharmacokinetic

Received

January 11, 2005

Accepted

March 2, 2005

Jpn. J. Chemother. 53 (S-1): 1-16, 2005