Dose-finding study on biapenem in complicated urinary tract infection

To find the optimal dose of biapenem (BIPM), a new parenteral carbapenem, in the treatment of complicated urinary tract infection, we performed a randomized, prospective, wellcontrolled study using imipenem/cilastatin (IPM/CS) as the control drug. The subjects had complicated urinary tract infection with pyuria of at least 5 WBCS/HPF, bacteriuria of at least 10⁴CFU/ml and identifiable underlying urinary tract disease. Only hospitalized patients without indwelling catheters were enrolled in the study. Patients were randomly assigned to receive 150 mg b. i. d. of BIPM (group L), 300 mg b. i. d. of BIPM (group H) or 500 mg/500 mg b. i. d. of IPM/CS (group C) by intravenous drip infusion for 5 days. Overall clinical efficacy was evaluated on the basis of criteria proposed by the Japanese UTI Committee as “excellent”, “moderate” or “poor”. Excellent and moderate responses were obtained in 78.9% of 19 patients in group L, 84.6% of 26 patients in group H and 81.0% of 21 patients in group C. The differences were not statistically significant. The bacteriological eradication rates achieved were 91.3% of 23 strains in group L, 90.9% of 33 strains in group H and 93.3% of 30 strains in group C, with no statistically significant differences. Clinical adverse reactions were experienced in 4.2% of 24 patients in group L, none of 28 patients in group H and none of 24 patients in group C, with no statistically significant differences. Clinical value also was not significantly different among the three groups. From the results obtained in this study, we concluded that the optimal daily dose of BIPM in the treatment of complicated urinary tract infection is 300 mg b. i. d.