Laboratory and clinical studies on FK037 in respiratory infection

FK037, the newly developed injectable cephem, was evaluated in vitro and in vivo. The results were as follows. 1) Antimicrobial activity: Minimal inhibitory concentrations (MICs) against 513 clinical isolates including 16 different species were determined by the microbroth dilution method and were compared with those of ceftazidime (CAZ), cefpirome, and cefuzonam (CZON). FK037 showed excellent antimicrobial activity at the same level as CZON against gram-positive bacteria including methicillinresistant Staphylococcus aureus, although the MICs were superior to that of CAZ. The MIC values of FK037 for gram-negative bacteria were equivalent to those of other cephems tested. 2) Clinical efficacy and adverse reactions: Seventeen patients with respiratory tract infections were treated with FK037, and the overall efficacy rate was 75%(excellent in 4, good in 8, fair in 1, poor in 3 and not evaluable in 1). Side effects of FK037 were not observed. As for abnormal laboratory findings, the elevation of GOT, GPT and ALP was observed in 1 case, the elevation of GOT in 1, the elevation of GPT in 1, leukopenia in 1, an increase in the number of eosinophils in 3, and mild elevation of serum potassium in 1. These abnormalities were all mild and transient, suggesting that FK037 is a useful and safe antibacterial agent.