Randomized, open-label, parallel-group, multicenter study of the efficacy and tolerability of IV gatifloxacin with the option for oral stepdown gatifloxacin versus IV ceftriaxone (with or without erythromycin or clarithromycin) with the option for oral stepdown clarithromycin for treatment of patients with mild to moderate community-acquired pneumonia requiring hospitalization.

Background: Empiric therapy for community-acquired pneumonia (CAP) requires the use of antibiotics with activity against a broad spectrum of respiratory pathogens and suitable pharmacokinetic properties to simplify IV-to-oral step-down therapy switches.

Objective: The aim of this study was to compare the efficacy and tolerability of IV gatifloxacin with the option for oral stepdown gatifloxacin with a standard regimen of IV ceftriaxone (with or without erythromycin or clarithromycin) with the option for oral stepdown clarithromycin in patients with mild to moderate CAP requiring hospitalization.

Methods: In a randomized, open-label, parallel-group, multicenter study, adults with CAP received 7 to 14 days of treatment with either IV gatifloxacin 400 mg QD with the stepdown option or IV ceftriaxone 1 or 2 g QD (with or without erythromycin 0.