1. Inpatients 20 years or over obtained by written consent2. Patients who are positive for COVID-19 by PCR or other methods based on gene amplification or antigen testing 3. Patients with a finding consistent with novel coronavirus pneumonia on chest CT examination4. Patients with room air SpO2 <96% at rest5. Patients who require less than 5 L/min oxygen concentration6. Patients who are not on a ventilator7. Patients whose AST or ALT value is 2.5 times or less than the institutional upper limit8. Patients whose total bilirubin level is 2.5 times or less than the institutional upper limit9. Patients with creatinine clearance (calculated by Cockcroft-Gault formula) of 30 mL/min or more

1. Inpatients 20 years or over obtained by written consent2. Patients who are positive for COVID-19 by PCR or other methods based on gene amplification or antigen testing 3. Patients with a finding consistent with novel coronavirus pneumonia on chest CT examination4. Patients with room air SpO2 <96% at rest5. Patients who require less than 5 L/min oxygen concentration6. Patients who are not on a ventilator7. Patients whose AST or ALT value is 2.5 times or less than the institutional upper limit8. Patients whose total bilirubin level is 2.5 times or less than the institutional upper limit9. Patients with creatinine clearance (calculated by Cockcroft-Gault formula) of 30 mL/min or more