The in vitro antimicrobial activity and serum and sputum concentrations of balofloxacin (BLFX: Q-35), a new-quinolone agent for oral use developed in Japan, and its therapeutic efficacy in the treatment of respiratory tract infections were evaluated. The minimum inhibitory concentrations (MICs) of BLFX, ofloxacin (OFLX), ciprofloxacin (CPFX), tosufloxacin (TFLX), sparfloxacin (SPFX), cefaclor (CCL) and rifampicin (RFP) against 20 strains each of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin- resistant S. aureus (MRSA), Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Serratia marcescens, and Pseudomonas aeruginosa, 18 strains each of Haemophilus influenzae and Mycobacterium intracellulare, and 22 strains each of Mycobacterium tuberculosis and Mycobacterium avium were determined by the micro-broth dilution method using the Dynatech MIC 2000 system. As shown by MICs, BLFX was as active as OFLX against all the species tested except for Mycobacteriaceae. BLFX was less active than OFLX against Mycobacteriaceae, but more active than but against RFP-resistant M. tuberculosis. Twenty one patients received a daily dose of 100 mg or 200 mg of BLFX per os for 3 to 21 days (mean; 10.7 days): 2 patients with acute bronchitis, 10 patients with acute pneumonia, 1 patient with Mycoplasma pneumoniae pneumonia, 2 patients with infection associated with bronchiectasis, 4 patients with chronic bronchitis and 1 patient with infection associated with pulmonary emphysema and 1 patient with infection associated with old pulmonary tuberculosis. Two cases were excluded from clinical evaluation. The clinical effects were excellent in 5 and good in 14 patients (efficacy rate: 100%). Five strains were identified as causative organisms: 3 strains of H. influenzae, one strain of K. pneumoniae and one strain of P. aeruginosa. All strains were eradicated. In one case of chronic bronchitis, the maximum concentration of BLFX in serum (1.57 μg/ml) was achieved 3 hours after oral administration of 200 mg and that in sputum (2.29μg/ml) 5 to 6 hours after administration, The ratio of the concentration of BLFX in sputum to that in serum was 146%. No adverse reactions were observed during treatment with BLFX. Eosinophilia was observed in three patients and a transient elevation of serum transaminase was observed in two patients. These adverse effects disappeared after the completion of therapy. We conclude from the above results that BLFX is one of the most useful quinolone agents for oral administration as a drug of first choice in the treatment of respiratory infections.
|Number of pages||12|
|Journal||Japanese Journal of Chemotherapy|
|Issue number||SUPPL. 5|
|Publication status||Published - 1995 Dec 1|
ASJC Scopus subject areas
- Pharmacology (medical)