* 1. severe 2019-ncov pneumonia met one of the following criteria: respiratory distress, rr ≥ 30 times / min, or sao2 / spo2 ≤ 93% in resting state, or arterial partial pressure of oxygen (pao2) /concentration of oxygen (fio2) ≤ 300mmhg (1mmhg = 0.133kpa) * 2. critical severe 2019-ncov pneumonia met one of the following criteria: respiratory failure and mechanical ventilation required, or shock, or combined with other organ failure required icu monitoring treatment * 3. severe liver disease (e.g. child pugh score ≥ c, ast \> 5 times upper limit) * 4. known allergic reaction to any of components of asc09 / ritonavir compound tablets * 5. patients with definite contraindications in the label of ritonavir * 6. positive serum pregnancy test result for women with childbearing potential at screening * 7. using hiv protease inhibitor drugs * 8. not suitable for the study, in the opinion of the investigator (e.g. patient may be transferred to another hospital during the study period, patient with multiple basic diseases, etc.)

* 1. severe 2019-ncov pneumonia met one of the following criteria: respiratory distress, rr ≥ 30 times / min, or sao2 / spo2 ≤ 93% in resting state, or arterial partial pressure of oxygen (pao2) /concentration of oxygen (fio2) ≤ 300mmhg (1mmhg = 0.133kpa) * 2. critical severe 2019-ncov pneumonia met one of the following criteria: respiratory failure and mechanical ventilation required, or shock, or combined with other organ failure required icu monitoring treatment * 3. severe liver disease (e.g. child pugh score ≥ c, ast \> 5 times upper limit) * 4. known allergic reaction to any of components of asc09 / ritonavir compound tablets * 5. patients with definite contraindications in the label of ritonavir * 6. positive serum pregnancy test result for women with childbearing potential at screening * 7. using hiv protease inhibitor drugs * 8. not suitable for the study, in the opinion of the investigator (e.g. patient may be transferred to another hospital during the study period, patient with multiple basic diseases, etc.)

- 1. severe 2019-ncov pneumonia met one of the following criteria: respiratory distress, rr ≥ 30 times / min, or sao2 / spo2 ≤ 93% in resting state, or arterial partial pressure of oxygen (pao2) /concentration of oxygen (fio2) ≤ 300mmhg (1mmhg = 0.133kpa) - 2. critical severe 2019-ncov pneumonia met one of the following criteria: respiratory failure and mechanical ventilation required, or shock, or combined with other organ failure required icu monitoring treatment - 3. severe liver disease (e.g. child pugh score ≥ c, ast > 5 times upper limit) - 4. known allergic reaction to any of components of asc09 / ritonavir compound tablets - 5. patients with definite contraindications in the label of ritonavir - 6. positive serum pregnancy test result for women with childbearing potential at screening - 7. using hiv protease inhibitor drugs - 8. not suitable for the study, in the opinion of the investigator (e.g. patient may be transferred to another hospital during the study period, patient with multiple basic diseases, etc.)

- 1. severe 2019-ncov pneumonia met one of the following criteria: respiratory distress, rr ≥ 30 times / min, or sao2 / spo2 ≤ 93% in resting state, or arterial partial pressure of oxygen (pao2) /concentration of oxygen (fio2) ≤ 300mmhg (1mmhg = 0.133kpa) - 2. critical severe 2019-ncov pneumonia met one of the following criteria: respiratory failure and mechanical ventilation required, or shock, or combined with other organ failure required icu monitoring treatment - 3. severe liver disease (e.g. child pugh score ≥ c, ast > 5 times upper limit) - 4. known allergic reaction to any of components of asc09 / ritonavir compound tablets - 5. patients with definite contraindications in the label of ritonavir - 6. positive serum pregnancy test result for women with childbearing potential at screening - 7. using hiv protease inhibitor drugs - 8. not suitable for the study, in the opinion of the investigator (e.g. patient may be transferred to another hospital during the study period, patient with multiple basic diseases, etc.)