The main objective of this study is to investigate the safety, pharmacokinetics (PK) and the relationship between PK and pharmacodynamics (Minimum Inhibitory Concentration [MIC] and Mutant Prevention Concentration [MPC]) of intravenous BAYQ3939 (400 mg BID and 400 mg TID) in hospitalized patients with bacterial pneumonia or secondary infection of chronic respiratory disease with severe disease or a poor response to other antimicrobials. In addition, the efficacy of the ciprofloxacin, in terms of clinical response and microbiological response, will be investigated, but as a secondary endpoint.

Inclusion Criteria:

• Males and non-pregnant, non-lactating females with written informed consent, 20 years of age or older.

• Within 48 hours prior to the first study drug administration, all patients should have the pathogens identified with appropriate specimens (e.g., sputum, tracheal aspirate, bronchoalveolar lavage [BAL], protected brushing specimen [PBS]), or should have appropriate specimens highly likely to identify the pathogens sampled. (However, the patients with Legionellosis is enrolled when the test of Legionella antigen is positive.)

• The following severe bacterial pneumonia meeting the diagnostic criteria of pneumonia or secondary infection of chronic respiratory disease

  • Severe pneumonia

    • Community-acquired pneumonia: PORT score III, IV or V
    • Hospital-acquired pneumonia [HAP]-Group B and with a low risk for multidrug-resistant pathogens
    • Patients with [HAP]-Group A whose pathogen is suspected to be Pseudomonas aeruginosa
    • Hospitalized patients with bacterial pneumonia with a poor response to other antimicrobials Note: The patients should be limited to CAP patients with PORT score III, IV or V and HAP patients with-Group A or B who don't respond to or have a poor response to other antimicrobials over 3day's treatment.2

  • Secondary infection of chronic respiratory disease

    • Patients who are hospitalized for the treatment of secondary infection of chronic respiratory disease
    • Hospitalized patients with secondary infection of chronic respiratory disease with a poor response to other antimicrobials Note: The patients should be limited to secondary infection of chronic respiratory disease patients who don't respond to or have a poor response to other antimicrobials over 3day's treatment.

Exclusion Criteria:

• Creatinine clearance (Ccr) ≤ 30 mL/min or nephrotic syndrome
• Patient with chronic treatment of immunosuppressive drug
• Decompensated congestive heart failure
• Subject who received more than 24 hours of an antibacterial drug for the current infection
• Patient who requires Intensive Care Unit (ICU) management [In case subjects who don't correspond to the severity for ICU management need to be admitted to ICU due to a circumstance of the site (e.g. shortage of hospital beds), those subjects shall not be excluded]
• Patients with infections other than pneumonia or secondary infection of chronic pulmonary disease
• Lung abscess, or empyema
• Viral, fungal, mycobacterial, or atypical pneumonia as a primary diagnosis
• Known or suspected bacteremia secondary to Staphylococcus aureus
• Known causative microorganisms other than indication (microorganisms) of the study drug, or positive in urinary antigen test of Streptococcus pneumonia
• Infection that necessitates the use of a concomitant antibacterial agent in addition to study medication [excluding subjects with concomitant use of long-term, low-dose macrolide for chronic respiratory diseases, sulbactam sodium/ampicillin sodium (Unasyn-S) and clindamycin (Dalacin-S)]
• Known bronchial obstruction or a history of post-obstructive pneumonia
• Known primary lung cancer