[Clinical trials of flomoxef in patients with chronic respiratory tract infections].

Flomoxef (FMOX, 6315-S), a newly developed oxacephem drug, was administered to 6 patients with chronic respiratory tract infections. Bacteriological examination of these infections using quantitative sputum cultures revealed that 2 patients had Haemophilus influenzae, 2 had Branhamella catarrhalis and 2 had mixed pathogens (one was with H. influenzae + B. catarrhalis and the other with Streptococcus pneumoniae + B. catarrhalis). The administration of the drug was done by drip infusion, twice daily, with a daily dose of 1 to 2 g. As results, all the above mentioned pathogenic organisms were eradicated in 5 to 10 days after the initiation of the drug therapy. No undesirable symptoms were observed in these patients during the course of the chemotherapy. Serum drug concentrations after an intravenous administration of the drug reached their peak values averaging 134.32 +/- 40.32 micrograms/ml immediately after a single dose of 2 g of FMOX in 5 patients with chronic respiratory tract infections. Drug concentration in the sputum was at highest 1.86 micrograms/ml. Susceptibilities to FMOX of clinically isolated 49 strains of H. influenzae and 35 strains of B. catarrhalis from our clinic in the year of 1986 were compared to those to ampicillin and to latamoxef (LMOX). The study revealed that MICs of FMOX against H. influenzae were 0.10 to 1.56 micrograms/ml, hence H. influenzae strains seemed to be sensitive to FMOX regardless of beta-lactamase activities. LMOX had higher activities against H. influenzae than FMOX, however. Activities of FMOX against B. catarrhalis, on the other hand, were distributed from less than 0.05 to 0.39 microgram/ml which were also not as good as LMOX activities.