Study to Evaluate the Efficacy and Safety of Oral Administration With Nemonoxacin and Levofloxacin in Patients With CAP

Inclusion Criteria: 1. Ages between 18 and 70; 2. Weighs between 40 \~ 100 kg, and BMI ≥ 18 kg/m2; 3. Must have a clinical diagnosis of CAP 4. Chest X-ray shows new or persist/progressive infiltrates 5. If female, non-lactating and at no risk or pregnancy (post-menopausal or must use adequate birth control) 6. The patient is able to take the drug orally. Exclusion Criteria: 1. 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 2. 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) 3. Clinically significant conduction or other abnormality on 12-lead ECG, or QTc interval 4. Potassium is \< 3.5 mmol/L 5. Any known disease that seriously affect the immune system 6. Active hepatitis or decompensated cirrhosis; 7. Have used quinolones or fluoroquinolones within 14 days before enrollment 8. Patients who are being or will be on a long-term medication of steroids