OBJECTIVES: Doripenem, a new carbapenem, has been approved for nosocomial pneumonia (NP) including ventilator-associated pneumonia (VAP), complicated intra-abdominal infections and complicated urinary tract infections in Europe. This study aimed at estimating the budgetary impact of adding doripenem to a hospital formulary for treatment of NP and VAP in Germany. METHODS: An Excel-based model was developed in accordance with Good Research Practices for Budget Impact Analysis disseminated by the ISPOR to estimate the annual impact on a hospital's budget of adding doripenem. Model inputs included annual hospital admissions for NP and VAP, current share of imipenem and meropenem use (50% each, no doripenem use), treatment duration and length of stay (LOS) from clinical trials and assumptions, hospitalization costs from published literature and Federal Health Monitoring, list prices for doripenem from the online pharmaceutical database Lauer-Taxe and discounted prices for imipenem and meropenem from IMS GPI Krankenhaus-Index. All costs were in 2008 Euros. A new proportional share of 50% doripenem, 30% imipenem and 20% meropenem was assumed for this analysis. Sensitivity analyses explored the impact on results of different proportions of doripenem use. RESULTS: The total cost per treated patient (based on NP/VAP pooled population) prior to the introduction of doripenem was estimated to be €12,513. With the new proportional share, total cost was estimated to decrease to €11,896, a 5% reduction in the hospital budget. Addition of doripenem led to a €617 savings per patient primarily due to a reduction in hospital days and days on mechanical ventilation. Increasing the proportion of doripenem use resulted in larger savings to the hospital budget (€1217 per patient at 100% doripenem use). CONCLUSIONS: Results indicate that adding doripenem to a hospital formulary for treatment of NP and VAP will yield potential savings to a hospital’s budget in Germany.