1. subjects who are known to have hypersensitivity to any component of the investigational drug; 2. subjects who meet diagnostic and treatment criteria for severe and critical cases in the diagnosis and treatment protocol for covid-19 (trial version 10) issued by national health commission of the people's republic of china; 3. abnormal hepatic function at screening: total bilirubin ≥ 1.5 × upper limit of normal (uln); alt or ast ≥ 3 × uln; 4. human immunodeficiency virus (hiv) antibody positive, treponema pallidum-specific antibody (tp-pa) positive or rapid plasma reagin (rpr) positive for syphilis at screening; 5. abnormal renal function at screening: serum creatinine ≥ 1.5 × uln; 6. subjects with impaired immune system (including those treated with corticosteroids\* or other immunosuppressants\*, or those with progression or recurrence of cancer) at screening; note: \*patients using skin preparations are allowed to be enrolled, but the skin preparations cannot be used in the eyes, nose or ears or by inhalation. 7. acute onset of chronic respiratory diseases, including bronchial asthma and chronic obstructive pulmonary disease at screening; 8. there are suspected or confirmed acute systemic infections except for covid-19 at the time of screening (for example, the pathogen detection indicates that it is complicated with influenza; there is a high possibility of bacterial infection as indicated by symptoms, signs, laboratory tests or imaging), which may interfere with the assessment of response to study intervention; 9. any comorbidity requiring surgery within 14 days prior to randomization or during the study, or any life-threatening comorbidity within 30 days prior to randomization as determined by the investigator; 10. subjects who are receiving hiv antiviral treatment at screening; 11. treatment with sars-cov-2 antiviral drugs within 14 days prior to randomization; 12. subjects who have received (within 30 days prior to randomization or within 5 drug half-lives, whichever is longer) or are expected to receive covid-19 monoclonal antibody, intravenous injection of covid-19 human immunoglobulin, or covid-19 convalescent plasma therapy; 13. subjects who have received any covid-19 vaccine within 28 days prior to randomization or planned to receive any covid-19 vaccine during the study; 14. any drug prohibited by the package insert of paxlovid that is currently used or expected to be used during treatment and within 4 days after the last dose of study drug, or any other drug or substance that is highly dependent on cytochrome p450 (cyp) 3a4, cyp2b6, cyp1a2, multidrug resistance gene 1 (mdr1) or organic anion transporting polypeptide (oatp) 1b3 for clearance; any potent cyp3a4 or mdr1 inducers used within 28 days prior to randomization or expected to be used during treatment and within 4 days after the last dose of study drug ; 15. pregnant or lactating women; 16. subjects who have participated in other clinical trials within 3 months prior to administration or are receiving other investigational drugs; 17. subjects with other conditions that, in the judgment of the investigator, make them unsuitable for participation in this study.

1. subjects who are known to have hypersensitivity to any component of the investigational drug; 2. subjects who meet diagnostic and treatment criteria for severe and critical cases in the diagnosis and treatment protocol for covid-19 (trial version 10) issued by national health commission of the people's republic of china; 3. abnormal hepatic function at screening: total bilirubin ≥ 1.5 × upper limit of normal (uln); alt or ast ≥ 3 × uln; 4. human immunodeficiency virus (hiv) antibody positive, treponema pallidum-specific antibody (tp-pa) positive or rapid plasma reagin (rpr) positive for syphilis at screening; 5. abnormal renal function at screening: serum creatinine ≥ 1.5 × uln; 6. subjects with impaired immune system (including those treated with corticosteroids\* or other immunosuppressants\*, or those with progression or recurrence of cancer) at screening; note: \*patients using skin preparations are allowed to be enrolled, but the skin preparations cannot be used in the eyes, nose or ears or by inhalation. 7. acute onset of chronic respiratory diseases, including bronchial asthma and chronic obstructive pulmonary disease at screening; 8. there are suspected or confirmed acute systemic infections except for covid-19 at the time of screening (for example, the pathogen detection indicates that it is complicated with influenza; there is a high possibility of bacterial infection as indicated by symptoms, signs, laboratory tests or imaging), which may interfere with the assessment of response to study intervention; 9. any comorbidity requiring surgery within 14 days prior to randomization or during the study, or any life-threatening comorbidity within 30 days prior to randomization as determined by the investigator; 10. subjects who are receiving hiv antiviral treatment at screening; 11. treatment with sars-cov-2 antiviral drugs within 14 days prior to randomization; 12. subjects who have received (within 30 days prior to randomization or within 5 drug half-lives, whichever is longer) or are expected to receive covid-19 monoclonal antibody, intravenous injection of covid-19 human immunoglobulin, or covid-19 convalescent plasma therapy; 13. subjects who have received any covid-19 vaccine within 28 days prior to randomization or planned to receive any covid-19 vaccine during the study; 14. any drug prohibited by the package insert of paxlovid that is currently used or expected to be used during treatment and within 4 days after the last dose of study drug, or any other drug or substance that is highly dependent on cytochrome p450 (cyp) 3a4, cyp2b6, cyp1a2, multidrug resistance gene 1 (mdr1) or organic anion transporting polypeptide (oatp) 1b3 for clearance; any potent cyp3a4 or mdr1 inducers used within 28 days prior to randomization or expected to be used during treatment and within 4 days after the last dose of study drug ; 15. pregnant or lactating women; 16. subjects who have participated in other clinical trials within 3 months prior to administration or are receiving other investigational drugs; 17. subjects with other conditions that, in the judgment of the investigator, make them unsuitable for participation in this study.

subjects who are known to have hypersensitivity to any component of the investigational drug; subjects who meet diagnostic and treatment criteria for severe and critical cases in the diagnosis and treatment protocol for covid-19 (trial version 10) issued by national health commission of the people's republic of china; abnormal hepatic function at screening: total bilirubin ≥ 1.5 × upper limit of normal (uln); alt or ast ≥ 3 × uln; human immunodeficiency virus (hiv) antibody positive, treponema pallidum-specific antibody (tp-pa) positive or rapid plasma reagin (rpr) positive for syphilis at screening; abnormal renal function at screening: serum creatinine ≥ 1.5 × uln; subjects with impaired immune system (including those treated with corticosteroids* or other immunosuppressants*, or those with progression or recurrence of cancer) at screening; note: *patients using skin preparations are allowed to be enrolled, but the skin preparations cannot be used in the eyes, nose or ears or by inhalation. acute onset of chronic respiratory diseases, including bronchial asthma and chronic obstructive pulmonary disease at screening; there are suspected or confirmed acute systemic infections except for covid-19 at the time of screening (for example, the pathogen detection indicates that it is complicated with influenza; there is a high possibility of bacterial infection as indicated by symptoms, signs, laboratory tests or imaging), which may interfere with the assessment of response to study intervention; any comorbidity requiring surgery within 14 days prior to randomization or during the study, or any life-threatening comorbidity within 30 days prior to randomization as determined by the investigator; subjects who are receiving hiv antiviral treatment at screening; treatment with sars-cov-2 antiviral drugs within 14 days prior to randomization; subjects who have received (within 30 days prior to randomization or within 5 drug half-lives, whichever is longer) or are expected to receive covid-19 monoclonal antibody, intravenous injection of covid-19 human immunoglobulin, or covid-19 convalescent plasma therapy; subjects who have received any covid-19 vaccine within 28 days prior to randomization or planned to receive any covid-19 vaccine during the study; any drug prohibited by the package insert of paxlovid that is currently used or expected to be used during treatment and within 4 days after the last dose of study drug, or any other drug or substance that is highly dependent on cytochrome p450 (cyp) 3a4, cyp2b6, cyp1a2, multidrug resistance gene 1 (mdr1) or organic anion transporting polypeptide (oatp) 1b3 for clearance; any potent cyp3a4 or mdr1 inducers used within 28 days prior to randomization or expected to be used during treatment and within 4 days after the last dose of study drug ; pregnant or lactating women; subjects who have participated in other clinical trials within 3 months prior to administration or are receiving other investigational drugs; subjects with other conditions that, in the judgment of the investigator, make them unsuitable for participation in this study.

subjects who are known to have hypersensitivity to any component of the investigational drug; subjects who meet diagnostic and treatment criteria for severe and critical cases in the diagnosis and treatment protocol for covid-19 (trial version 10) issued by national health commission of the people's republic of china; abnormal hepatic function at screening: total bilirubin ≥ 1.5 × upper limit of normal (uln); alt or ast ≥ 3 × uln; human immunodeficiency virus (hiv) antibody positive, treponema pallidum-specific antibody (tp-pa) positive or rapid plasma reagin (rpr) positive for syphilis at screening; abnormal renal function at screening: serum creatinine ≥ 1.5 × uln; subjects with impaired immune system (including those treated with corticosteroids* or other immunosuppressants*, or those with progression or recurrence of cancer) at screening; note: *patients using skin preparations are allowed to be enrolled, but the skin preparations cannot be used in the eyes, nose or ears or by inhalation. acute onset of chronic respiratory diseases, including bronchial asthma and chronic obstructive pulmonary disease at screening; there are suspected or confirmed acute systemic infections except for covid-19 at the time of screening (for example, the pathogen detection indicates that it is complicated with influenza; there is a high possibility of bacterial infection as indicated by symptoms, signs, laboratory tests or imaging), which may interfere with the assessment of response to study intervention; any comorbidity requiring surgery within 14 days prior to randomization or during the study, or any life-threatening comorbidity within 30 days prior to randomization as determined by the investigator; subjects who are receiving hiv antiviral treatment at screening; treatment with sars-cov-2 antiviral drugs within 14 days prior to randomization; subjects who have received (within 30 days prior to randomization or within 5 drug half-lives, whichever is longer) or are expected to receive covid-19 monoclonal antibody, intravenous injection of covid-19 human immunoglobulin, or covid-19 convalescent plasma therapy; subjects who have received any covid-19 vaccine within 28 days prior to randomization or planned to receive any covid-19 vaccine during the study; any drug prohibited by the package insert of paxlovid that is currently used or expected to be used during treatment and within 4 days after the last dose of study drug, or any other drug or substance that is highly dependent on cytochrome p450 (cyp) 3a4, cyp2b6, cyp1a2, multidrug resistance gene 1 (mdr1) or organic anion transporting polypeptide (oatp) 1b3 for clearance; any potent cyp3a4 or mdr1 inducers used within 28 days prior to randomization or expected to be used during treatment and within 4 days after the last dose of study drug ; pregnant or lactating women; subjects who have participated in other clinical trials within 3 months prior to administration or are receiving other investigational drugs; subjects with other conditions that, in the judgment of the investigator, make them unsuitable for participation in this study.

has hypersensitivity or other contraindication to any of the components of the study interventions. patients with severe or critical covid-19. active liver disease, or obvious abnormal liver function (alt or ast ≥ 3uln, or total bilirubin ≥ 1.5uln). receiving dialysis or have known moderate to severe renal impairment. compromised immune system. acute episode of chronic respiratory diseases, including bronchial asthma, chronic obstructive pulmonary disease. suspected or confirmed concurrent active systemic infection other than covid-19. any comorbidity requiring surgery within 14 days prior to study entry, or that is considered life-threatening within 30 days prior to study entry, as determined by the investigator. treatment with antivirals against sars-cov-2 within 14 days prior to randomization. current or expected use of strong cyp3a4 inducers, inhibitors or medications that are highly dependent on cyp3a4 for clearance. has received or is expected to receive covid-19 monoclonal antibody or convalescent covid-19 plasma during study treatment. has received any sars-cov-2 vaccine within 3 months prior to randomization. participating in another interventional clinical study with an investigational compound or device. pregnant, lactating women or those with a positive pregnancy test. previous administration with any investigational drug within 3 months before the study drug administration. participants who are judged by the investigator to be unsuitable to participate in this study.

has hypersensitivity or other contraindication to any of the components of the study interventions. patients with severe or critical covid-19. active liver disease, or obvious abnormal liver function (alt or ast ≥ 3uln, or total bilirubin ≥ 1.5uln). receiving dialysis or have known moderate to severe renal impairment. compromised immune system. acute episode of chronic respiratory diseases, including bronchial asthma, chronic obstructive pulmonary disease. suspected or confirmed concurrent active systemic infection other than covid-19. any comorbidity requiring surgery within 14 days prior to study entry, or that is considered life-threatening within 30 days prior to study entry, as determined by the investigator. treatment with antivirals against sars-cov-2 within 14 days prior to randomization. current or expected use of strong cyp3a4 inducers, inhibitors or medications that are highly dependent on cyp3a4 for clearance. has received or is expected to receive covid-19 monoclonal antibody or convalescent covid-19 plasma during study treatment. has received any sars-cov-2 vaccine within 3 months prior to randomization. participating in another interventional clinical study with an investigational compound or device. pregnant, lactating women or those with a positive pregnancy test. previous administration with any investigational drug within 3 months before the study drug administration. participants who are judged by the investigator to be unsuitable to participate in this study.