1994 Volume 42 Issue Supplement4 Pages 64-81
The in vitro and in vivo antibacterial activities of biapenem (BIPM), a new 4-methyl carbapenem antibiotic were investigated, and were compared with those of imipenem/cilastatin (IPM/CS), meropenem (MEPM), ceftazidime (CAZ), flomoxef (FMOX), cefsulodin (CFS), cefoperazone (CPZ) and piperacillin (PIPC). BIPM had a broad antibacterial spectrum against Gram-positive and-negative bacteria, such as IPM and MEPM. Against almost all of Gram -negative clinical isolates, BIPM was more active than IPM. Especially, BIPM was the most active in the all antibiotics tested against Pseudomonas aeruginosa. BIPM showed dose-related bactericidal activity against Staphylococcus aureus, Escherichia coli and P. aeruginosa. Only, BIPM induced spherical cell formation in E. coli under the concentration of 1 MIC. In P. aeruginosa, BIPM and IPM induced bulge formation. On the other hand, MEPM induced filamentous cell formation. The morphological change was due to affinity for PBP-2 in E. coli and PBP-1 A, -2 and -4 in P. aeruginosa. The therapeutical effect of BIPM against systemic infection in mice was superior to that of IPM against E. coli, S. marcescens, P. aeruginosa and A. calcoaceticus and superior to that of MEPM against S. aureus, S. pneumoniae, P.aeruginosa, A. calcoaceticus, but similar to that of MEPM against E. coli, K. pneumoniae and S.marcescens. Against the experimental systemic infection and experimental urinary tract infection with P. aeruginosa, BIPM was the most active in all the antibiotics tested.
