Usefulness of levofloxacin at 200 mg b.i.d. for suspected pneumococcal pneumonia

• Published in: Japanese Journal of Chemotherapy Vol. 52; no. 12; pp. 793 - 803
• Main Authors: Niki Yoshihito, Matsushima Toshiharu, Yamaguchi Keizo, Kohno Shigeru, Watanabe Akira, Odagiri Shigeki, Aoki Nobuki, Saito Atsushi
• Format: Journal Article
• Language: Japanese
• Published: Japanese Society of Chemotherapy 2004; 公益社団法人 日本化学療法学会
• Subjects: AUC/MIC; levofloxacin; PK/PD; pneumonia; Streptococcus pneumoniae
• ISSN: 1340-7007; 1884-5886
• DOI: 10.11250/chemotherapy1995.52.793

We studied the efficacy and safety of levofloxacin (LVFX) at 200 mg b.i.d. for 7 days, and the correlation between efficacy and the AUC/MIC ratio in patients with suspected pneumococcal pneumonia. Subjects were suspected of having mild to moderate pneumococcal pneumonia because pneumococcal antigen was detected in the urine or Gram staining of sputum was positive before the start of treatment. We measured blood LVFX twice in each patient and used the Bayesian method with population parameters to calculate AUC.Of the 71 subjects enrolled, 57 were analyzed for clinical efficacy, and efficacy was 93.0%(53/57). Of these, 46 had pneumococcal pneumonia, diagnosed as positive for Streptococcus pneumoniae by culture or urinary antigen. Efficacy was 93.5%(43/46). Of the 30 in whom S. pneumoniae was isolated and identified, bacterial eradication was 96.7%(29/30).Side effects occurred in 17 of 70 patients, i.e., 15 mild, and LVFX administration was continued. Two had moderate side effects and recovered quickly after LVFX administration was discontinued.The AUC/MIC ratio calculated for 22 patients in whom the MIC of LVFX for S. pneumoniae could be measured was 68.5±31.9 (mean±S.D.). Of these, only 1 patient was AUC/MIC < 25.Considering from above results, it was suggested that 200 mg LVFX administered twice a day could achieve an adequate AUC/MIC ratio and high clinical efficacy in patients with suspected pneumococcal pneumonia. 経口ニューキノロン薬であるlevonoxacin (LVFX) を用い, 肺炎球菌感染が疑われる肺炎患者を対象として, 1回200mg, 1日2回, 7日間投与における有効性ならびに安全性の検討を行った。また有効性とAUC/MICとの相関性についても検討した。対象患者は, 試験開始前に尿中の肺炎球菌抗原が陽性もしくは喀痰グラム染色により肺炎球菌の感染が疑われた軽症～ 中等症の肺炎患者とし, AUCの算出は, 症例ごとに2点の血中濃度を測定し母集団のパラメータよりベイジアン推定法を用いて算出した。本試験に組み人れられた全71例中, 臨床効果解析対象57例における有効率は93.0%(53/57) であり, そのうち肺炎球菌が培養陽性もしくは同尿中抗原が陽性であったことにより肺炎球菌性肺炎と診断された患者は46例で, その有効率は93.5%(43/46) であった。菌消失率は肺炎球菌培養陽性例で96.7%(29/30) であった。副作用は, 安全性評価対象70例中17例にみられ, うち15例は軽微でLVFXの投与は継続され, 2例の中等度の症例については投与を中止したが, その後速やかに回復した。LVFXに対する肺炎球菌のMICの測定が可能であった22例におけるAUC/MICは68.5±31.9 (mean±S.D.) であり, うちAUC/MICが25を下回ったのは1例のみであった。以上の結果より, 肺炎球菌感染が疑われる肺炎患者に対するLVFXの1回200mg・1日2回投与法は, 大部分の症例で十分なAUC/MICが得られ, 高い臨床的有用性が期待できるものと考えられた。