Study objective: To determine the cost-effectiveness of sequential TV to oral gatifloxacin therapy vs IV ceftriaxone with or without IV erythromycin to oral clarithromycin therapy to treat community-acquired pneumonia (CAP) patients requiring hospitalization. Patients: Two hundred eighty-three patients enrolled in a randomized, double-blind, clinical trial were eligible for inclusion in the cost-effectiveness analysis. Methods: Data collected included patient demographics, clinical and microbiological outcomes, length of stay (LOS), and antibiotic-related LOS (LOSAR). Costs evaluated include drug acquisition (level 1); plus costs of preparation, dispensing, and administration, treating adverse events, and clinical failures (level 2); plus hospital per diem costs (level 3). Robustness of economic findings was tested using sensitivity analyses. Results: Two hundred three patients were clinically and economically evaluable (98 receiving gatifloxacin and 105 receiving ceftriaxone). IV erythromycin was administered to 35 patients in the ceftriaxone-treated group. Oral conversion was achieved in 98% of patients in each group. Clinical cure and microbiological eradication rates did not differ statistically (98% and 97% with gatifloxacin vs 92% and 92% with ceftriaxone, respectively). Overall, neither geometric mean LOS nor LOSAR differed significantly (4.2 days and 4.1 days with gatifloxacin vs 4.9 days and 4.9 days with ceftriaxone, respectively). Treatment failures in the ceftriaxone group contributed to a mean incremental increase in LOSAR of 1.09 days and increased mean cost per patient. The geometric mean costs per patient (level 3) were $5,109 for gatifloxacin and $6,164 for ceftriaxone (p = 0.011). The cost-effectiveness ratios (mean cost per expected success) were $5,236:1 and $7,047:1 for gatifloxacin and ceftriaxone, respectively. Conclusions: Gatifloxacin monotherapy for CAP patients requiring hospitalization is clinically effective and provides an economic advantage compared to the regimen of ceftriaxone with or without erythromycin IV with a switch to oral clarithromycin.
