Abstract
Pazufloxacin (PZFX) and ofloxacin (OFLX) were administered as single oral doses of 200 mg to 6 male volunteers in a cross over fashion to compare their antibacterial effects on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa in clinically isolated urine samples. The maximum mean drug concentration in urine was 763μg/ml in the PZFX group (0-2 hours after administration) and 281μg/ml in the OFLX group (after 2-4 hours). The urinary antibacterial titer in the PZFX group was revealed to be superior to that in the OFLX group up to 4 hours after administration. In particular, while the samples, even of the undiluted urine, in the OFLX group showed no antibacterial activity against quinolone-moderately resistant S. aureus, E. coli and P. aeruginosa, all samples in the PZFX group, including those of dilute urine, showed some antibacterial activity up to 4 hours after administration. Theses results appear to reflect the excedllent antibacterial effect and higher initial urinary concentration of PZFX as compared with that of OFLX. When the MIC in urine was compared with that in CAMHB, PZFX and OFLX showed decreased antibacterial activity in urine. A decrease in bacterial activity in urine, if present, was about 2 tubes in the case of PZFX. OFLX, on the other hand, showed decreased antibacterial activity especially against E. coli which exceeded 5 tubes.
