The penetration of balofloxacin to sputum and its clinical effects on respiratory infectious diseases

A new oral quinolone drug, balofloxacin, was orally administered at a single dose of 100 mg to an elderly patient with bronchiectasis. The serum level increased with time from 0.26 μg/ml at 2 hours after administration to 1.54 μg/ml at 12 hours after administration. The sputum level also rose in approximately parallel with the serum level. The drug was also repeatedly administered, at a dose of 200 mg (in 2 divisions) or 400 mg (in 2 divisions), to 24 patients with respiratory infectious diseases. The efficacy was rated as excellent in 9 and good in 13, all of whom showed improvement in infectious symptoms (efficacy rate, 91.7%). The drug was particularly useful for 17 patients with pneumonia, who included 6 with mycoplasmal pneumonia; efficacy was excellent or good in all 17. Four of 5 pyogenic bacterial strains isolated were eradicated. Mild headache appeared in one patient as a side effect after 6 days of administration at 400 mg (in 2 divisions). Abnormal changes in clinical laboratory test values included elevated transaminases in 4, thrombocytosis in 1, and eosinophilia in 1, all of which were mild. These results suggest that this new quinolone drug, for oral use, is useful for treating respiratory infectious diseases, particularly pneumonia.