Abstract
Basic and clinical studies on grepafloxacin (GPFX), a new oral sythetic quinolone antimicrobial, were performed, and the following results were obtained.
1. The MIC90 range of GPFX against methicillin-sensitive Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli and Acinetobacter calcoaceticus was distributed from 0.025 to 0.2μg/ml, and was superior to those of ofloxacin (OFLX) and norfloxacin, and equivalent to or better than those of tosufloxacin (TFLX) and ciprofloxacin (CPFX).The MIC50 of CPFX against methicillin-resistant S.aureus was 0.2 μg/ml, thebest, while the MIC90 was 25μg/ml, inferior to that of TFLX, The MIC50 and MIC90 of GPFX against Pseudomonas aeruginosa showed antimicrobial activities of 0.78μg/ml and 3.13 μg/ml, respectively, equivalent to CPFX even though inferior to TFLX.
2. The MIC range of GPFX against Chlamydia pneumoniae, Chlamydia psittaci and Chlamydia trachomatis was distributed from 0.03 to 0.125 μg/ml, showing results superior to alreadyexisting new quinolone preparations such as TFLX and OFLX.
3. In the study on the clinical effects of GPFX, the results for 13 cases with respiratory diseases, including pneumonia and chronic respiratory tract infections, were markedly effective in 3 cases, effective in 5 cases, slightly effective in one case, ineffective in 3 cases and unevaluable in one case, an efficacy rate of 67%(8/12).
In the bacteriological study, the results for 10 cases in which causative bacteriawere isolated were as follows: eradicated in 4 cases, decreased or partially eradicated in 4 cases, unchanged in 1 case, and replaced in 1 case, an eradication rate of 50%. Of 4 strains of S. aureus, 3 were eradicated and 1 unchanged. Of 2 strains of S. pneumoniae, 1 was eradicated and 1 unchanged. One strain of E. coli and 3 strains of H. influenzae were all eradicated. Of 2 strains of K. pneumoniae, 1 was eradicated and 1 unchanged. The 2 strains of P. aeruginosa were both unchanged.
No side effects were observed, and the only abnormal laboratory finding was eosinophilia in one case.
