Ventilator-Associated Pneumonia/Hospital-Acquired Pneumonia Requiring Mechanical Ventilatory Support

• Drug: MERREM I.V. 2g as a 3 hour infusion every 8 hours
• Drug: vancomycin I.V. 1 g every 12 hours
• Drug: tobramycin I.V. 5 mg/kg every 24 hours
• Drug: MERREM I.V. 1g as a 30 minute infusion every 8 hours
• Drug: MERREM I.V. 500 mg as a 3 hour infusion every 8 hours

Inclusion Criteria:

• Onset or exacerbation of pneumonia at least 72 hours after admission to an acute care facility or onset of pneumonia in a nursing home or rehabilitation facility with subsequent transfer to an acute care facility
• Diagnosis of hospital-acquired pneumonia requiring mechanical ventilatory support
• Patient or Patient's legal guardian must sign written informed consent for study participation, pretreatment, and Day 7 bronchoscopy

Exclusion Criteria:

• Patients with hospital-acquired pneumonia caused by pathogens resistant to MERREM
• Patients with allergies to cephalosporins, penicillins and carbapenems
• Patients taking anticonvulsant therapy for a known seizure disorder
• Patients with lung cancer
• Patients with cystic fibrosis, acquired immune deficiency syndrome (AIDS), neutropenia, active tuberculosis, or patients taking immunosuppressive therapy in preparation for or following an organ transplant.
• Patients who are pregnant or breast feeding
• Patients who are unlikely to survive
• Patients with certain infections in another area requiring treatment with additional antibiotics
• Patients with other underlying conditions that would make it difficult to interpret response to study drug.
• Patients who have been part of another clinical study 30 days before entry into this study.
• Patients with hypotension (systolic BP < 85mmHg) or acidosis (arterial pH <7.25 or serum bicarbonate <15 mg/dl) despite attempts at fluid resuscitation
• Patients with profound hypoxia