The purpose of this study is to compare the safety and effectiveness of doripenem in patients with hospital-acquired pneumonia (HAP).

Doripenem is an antibiotic medication not yet approved by the US FDA. This is a phase 3, multicenter, prospective, open-label (though with blinded outcome assessments), randomized study of doripenem versus a comparator antibiotic in patients with hospital-acquired pneumonia. The study consists of screening phase, open-label treatment phase, and follow-up. Both patients on ventilator and not on ventilator are enrolled. The primary endpoint is the clinical response rate at early follow-up visit. The patients may receive either doripenem or comparator; total duration of the treatment is 7 to 14 days.

Inclusion Criteria:

• Patients hospitalized for >= 48 hours or those with prior hospital admission of at least 48 hours who were discharged within the last 48 hours.

Exclusion Criteria:

• Hospital-acquired pneumonia known at the time of enrollment to be caused by pathogen(s) resistant to certain antibiotics
• Any rapidly progressing disease or immediately life-threatening illness