Antibacterial activity of TOC-50, a new parenteral cephalosporin against penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae

Chemotherapy. 1997 Jan-Feb;43(1):1-5. doi: 10.1159/000239527.


TOC-50, a new parenteral cephalosporin, was assessed for antibacterial activity in vitro and in vivo. In vitro, the activity of TOC-50 was greater than ampicillin, erythromycin and gentamycin, and was equal to that of imipenem. The MICs of TOC-50 for 90% of the clinical isolates tested (MIC90 values) were 0.0125 microgram/ml for penicillin-susceptible Streptococcus pneumoniae, 0.2 microgram/ml for intermediately penicillin-resistant S. pneumoniae, and 0.39 microgram/ml for fully penicillin-resistant S. pneumoniae. In murine systemic-infection models, TOC-50 had a potent protective activity against penicillin-susceptible of fully penicillin-resistant S. pneumoniae. Its protective activity was stronger than that of imipenem.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Cephalosporins / pharmacology*
  • Imipenem / pharmacology
  • Japan
  • Male
  • Mice
  • Microbial Sensitivity Tests
  • Penicillin G / pharmacology
  • Penicillin Resistance / genetics
  • Penicillins / pharmacology
  • Streptococcal Infections / drug therapy
  • Streptococcus pneumoniae / drug effects*
  • Streptococcus pneumoniae / genetics
  • Thienamycins / pharmacology


  • Cephalosporins
  • Penicillins
  • TOC 50
  • Thienamycins
  • Imipenem
  • Penicillin G