Studies on general guidelines for the evaluation of new antimicrobial agents for the treatment of respiratory tract infections - I. Acute upper respiratory tract infections

'General guidelines for the evaluation of the new antimicrobial agents for the treatment of respiratory tract infections' was reported by our committee in the Japanese Journal of Chemotherapy ('General Guidelines' Vol. 45: 762-778, 1997). The aim of the present paper is to discuss the validity of the above 'General Guidelines', when applied for the study of the cases with acute upper respiratory tract infections (AURTI), and, if necessary, to set up a new guideline of the therapeutics of AURTI. For this purpose, a total of 2,257 cases with acute pharyngitis, acute tonsillitis or with acute bronchitis, which had been enlisted for the phase II and phase III clinical studies of new antimicrobials in Japan, were enrolled in the present study. Most of them were selected and enrolled on the basis of the judgement by investigators, and 1,518 cases (67%) were found to fulfil the criteria of 'General Guidelines'. All of the 5 different measurements recommended by the ad hoc committee (microbial study, WBC counts, stab count, CRP level and body temperature) were done only in 1,172 enrolled cases, and 947 cases (81%) were found to fulfil the new diagnostic criteria. The degree of the severity of the disease judged by investigators differed somewhat each other between the per os medication cases and the parenteral medication cases, and the number of moderate cases was the largest. However, the number of mild cases was the largest according to the 'General Guidelines'. Of 1,518 cases which fulfilled the new criteria, the ratio of mild/moderate/severe cases by the judgement of investigators was 41/50/9 and that by the new criteria was 50/39/11. The ad hoc committee stated that laboratory examinations at the 7 th day after initiation of chemotherapy were 'a must' for the correct evaluation of the effectiveness of antimicrobials administered. However, laboratory examinations at the 7 th day were done only in 234 cases, the judgement by investigators was comparable to that by the committee in 203 of 234 cases (87%). As a conclusion, the new guideline set up by the ad hoc committee is appropriate for the diagnosis, evaluation of severity of diseases, and for the evaluation of the effectiveness of antimicrobial agents used for the treatment of AURTI.