This study will test the safety and efficacy of TG-873870(Nemonoxacin) compared with Levofloxacin in adult patients with Community-Aquired Pneumonia(CAP)

Community-acquired Pneumonia(CAP) remains a leading cause of death in both developing and developed countries. In the choice of antibacterial agents used to treat CAP, fluoroquinolones have received considerable attention because of their wide spectrum of bactericidal activity. TG-873870(Nemonoxacin), a non-fluorinated quinolone (NFQ), is a selective bacterial topoisomerase inhibitor. This study will test the safety and efficacy of TG-873870(Nemonoxacin) compared with Levofloxacin in adult patients with Community-Aquired Pneumonia (CAP) .

Inclusion Criteria:

• If female, non-lactating and at no risk or pregnancy (post-menopausal or must use adequate birth control)
• Must be a suitable candidate for oral antibiotic therapy and must be able to swallow capsules intact
• Must have a clinical diagnosis of CAP based on clinical evidence
• Must have a chest radiograph demonstrating new or persistent/progressive infiltrates
• Must be able to produce sputum

Exclusion Criteria:

• Clinically significant conduction or other abnormality on 12-lead ECG, or QTc interval
• Patients with CAP that, in the investigator's judgment, is severe enough to require hospitalization for intravenous antibiotic therapy and/or supplemental oxygen therapy with ICU support
• Known or suspected severe bronchiectasis, cystic fibrosis, active pulmonary tuberculosis or infection with other mycobacteria or fungi, known bronchial obstruction, a history of post-obstructive pneumonia, other confounding respiratory diseases, such as lung cancer, malignancy metastatic to the lungs, lung abscess, empyema, suspected aspiration pneumonia due to vomiting, or non-bacterial respiratory infection (chronic obstructive pulmonary disease [COPD] is not exclusionary)
• Infection acquired in a hospital, nursing home, or other long-term care facility, or hospitalization for any reason within the previous 14 days
• Treatment with any antibiotics within the past 7 days prior to randomization, unless documents to be a treatment failure(72 hours treatment and not responding)
• Anticipation of the requirement for additional treatment with non-study antibacterials for any reason during the patient's participation in the study
• Treatment with chemotherapeutic agents or oncolytics during the 6 months prior to randomization or anticipated requirement for such agents during the course of the study
• Known or suspected CNS disorder that may predispose the patient to seizures or lower the seizure threshold