Early switch therapy from intravenous sulbactam/ampicillin to oral garenoxacin in patients with community-acquired pneumonia: a multicenter, randomized study in Japan

The switch from intravenous to oral antibiotic therapy is recommended for treating hospitalized patients with community-acquired pneumonia (CAP). We performed a multicenter, randomized study to assess the benefit of switching from intravenous sulbactam/ampicillin (SBT/ABPC) to oral garenoxacin (GRNX) in patients with CAP. Among adult CAP patients who must be hospitalized for intravenous antibiotic treatment, those with Pneumonia Patient Outcomes Research Team (PORT) scores of II-IV (mild to moderate) were initially treated with intravenous SBT/ABPC (6 g/day) for 3 days. A total of 108 patients who fulfilled the inclusion criteria (improved respiratory symptoms, CRP < 15 mg/dl, adequately improved oral intake, fever ≤ 38 °C for ≥ 12 h), were divided into two groups based on the antibiotic administered, the GRNX (switch to GRNX 400 mg/day) and SBT/ABPC groups (continuous administration of SBT/ABPC), for 4 days. Improvement in clinical symptoms, chest radiographic findings, and clinical effectiveness were evaluated by a central review board. Improvement in clinical symptoms was 96.3 and 90.2 % in the GRNX and SBT/ABPC groups, respectively. Improvement in chest radiographic findings was 94.4 and 90.2 % and clinical effectiveness was 94.4 and 90.2 % in the GRNX and SBT/ABPC groups, respectively. Microbiological efficacy was 90.9 and 69.2 % in the GRNX and SBT/ABPC groups, respectively. There were no significant differences between the groups. Converting to GRNX was as effective as continuous SBT/ABPC treatment in mild to moderate CAP patients in whom initial intravenous antibiotic treatment was successful.