[Clinical study on dosage schedule of tobramycin: controlled comparison between 180 mg b.i.d. and t.i.d]

The efficacy and safety of tobramycin (TOB) administration at 90 mg twice a day (90 mg group) to patients with respiratory tract infections (RTI) were objectively investigated by means of a well-controlled comparative study. The results in this 90 mg group were compared with the case of administering 3 times a day of 60 mg each (60 mg group) as the control. In both of these patient groups, TOB was administered by intramuscular injection for 10 consecutive days. This study included 85 patients (90 mg group: 43 patients; 60 mg group: 42 patients). The Committee, however, excluded 19 patients consisting of 13 cases of infection other than RTI and 6 cases of out of protocol drug administration. Thus, 66 patients (90 mg group: 32 patients; 60 mg group: 34 patients) were used for the efficacy analysis. All 85 patients were used, however, for the evaluation of the safety of TOB and for the usefulness of TOB as judged by the physicians in charge. A brief summary of the results is presented below. The cases employed by the Committee consisted of 8 and 17 cases in the 90 mg and 60 mg groups, respectively, with bacterial pneumonia and lung abscess, and 24 and 17 cases in the 90 mg and 60 mg groups, respectively, with chronic RTI. There was a tendency for the distribution of disease cases in the 2 drug groups to be significant. Within the chronic RTI disease classification, the number of patients with chronic bronchitis was almost equal in the 2 drug groups; 16 cases in the 90 mg group and 15 cases in the 60 mg group. However, secondary infections were diagnosed in 8 cases in the 90 mg group and 2 cases in the 60 mg group. The clinical efficacy judged for all cases investigated by the Committee showed efficacy ratios of 56.3% for the 90 mg group and 70.6% for the 60 mg group. The difference between the 2 drug groups was not statistically significant. In the treatment of bacterial pneumonia and lung abscess, the efficacy rate in the 90 mg group was 87.5%, while it was 88.2% in the 60 mg group; these high values were practically identical. Against chronic RTI, the efficacy rates were 45.8% in the 90 mg group and 52.9% in the 60 mg group; within that disease classification, the efficacy rates against the chronic bronchitis cases were nearly the same at 43.8% and 46.7%, respectively. These data showed no statistically significant differences between the 2 drug administration groups. (ABSTRACT TRUNCATED AT 400 WORDS)