1. prior tracheostomy; 2. concomitant treatment of respiratory support (involving any form of oxygen therapy); 3. any clinical contraindications, as judged by the attending physician; 4. any symptoms consistent with covid-19; 5. pregnant; 6. mentally or neurologically disabled patients who are considered not fit to consent to their participation in the study; 7. prior covid-19 infection. treatment sub study inclusion criteria: 1. capable of understanding and providing signed informed consent and ability to adhere to the requirements and restrictions of this protocol; 2. men and women ≥ 19 years of age unless local laws dictate otherwise; 3. english speaking; 4. must be willing to use an adequate form of contraception (or abstinence) from the time of the first dose with the imp until after the last dose of imp; 5. positive covid-19 test or presentation of clinical symptoms defined as fatigue with either fever \>37.2 (oral) and/or a persistent cough. treatment sub study

1. prior tracheostomy; 2. concomitant treatment of respiratory support (involving any form of oxygen therapy); 3. any clinical contraindications, as judged by the attending physician; 4. any symptoms consistent with covid-19; 5. pregnant; 6. mentally or neurologically disabled patients who are considered not fit to consent to their participation in the study; 7. prior covid-19 infection. treatment sub study inclusion criteria: 1. capable of understanding and providing signed informed consent and ability to adhere to the requirements and restrictions of this protocol; 2. men and women ≥ 19 years of age unless local laws dictate otherwise; 3. english speaking; 4. must be willing to use an adequate form of contraception (or abstinence) from the time of the first dose with the imp until after the last dose of imp; 5. positive covid-19 test or presentation of clinical symptoms defined as fatigue with either fever \>37.2 (oral) and/or a persistent cough. treatment sub study

prior tracheostomy; concomitant treatment of respiratory support (involving any form of oxygen therapy); any clinical contraindications, as judged by the attending physician; any symptoms consistent with covid-19; pregnant; mentally or neurologically disabled patients who are considered not fit to consent to their participation in the study; prior covid-19 infection. treatment sub study inclusion criteria: capable of understanding and providing signed informed consent and ability to adhere to the requirements and restrictions of this protocol; men and women ≥ 19 years of age unless local laws dictate otherwise; english speaking; must be willing to use an adequate form of contraception (or abstinence) from the time of the first dose with the imp until after the last dose of imp; positive covid-19 test or presentation of clinical symptoms defined as fatigue with either fever >37.2 (oral) and/or a persistent cough. treatment sub study

prior tracheostomy; concomitant treatment of respiratory support (involving any form of oxygen therapy); any clinical contraindications, as judged by the attending physician; any symptoms consistent with covid-19; pregnant; mentally or neurologically disabled patients who are considered not fit to consent to their participation in the study; prior covid-19 infection. treatment sub study inclusion criteria: capable of understanding and providing signed informed consent and ability to adhere to the requirements and restrictions of this protocol; men and women ≥ 19 years of age unless local laws dictate otherwise; english speaking; must be willing to use an adequate form of contraception (or abstinence) from the time of the first dose with the imp until after the last dose of imp; positive covid-19 test or presentation of clinical symptoms defined as fatigue with either fever >37.2 (oral) and/or a persistent cough. treatment sub study

1. prior tracheostomy; 2. concomitant treatment of respiratory support (involving any form of oxygen therapy); 3. any clinical contraindications, as judged by the attending physician; 4. any symptoms consistent with covid-19; 5. pregnant; 6. mentally or neurologically disabled patients who are considered not fit to consent to their participation in the study; 7. prior covid-19 infection. treatment sub study inclusion criteria: 1. capable of understanding and providing signed informed consent and ability to adhere to the requirements and restrictions of this protocol; 2. men and women ≥ 19 years of age unless local laws dictate otherwise; 3. english speaking; 4. must be willing to use an adequate form of contraception (or abstinence) from the time of the first dose with the imp until after the last dose of imp; 5. positive covid-19 test or presentation of clinical symptoms defined as fatigue with either fever >37.2 (oral) and/or a persistent cough. treatment sub study

1. prior tracheostomy; 2. concomitant treatment of respiratory support (involving any form of oxygen therapy); 3. any clinical contraindications, as judged by the attending physician; 4. any symptoms consistent with covid-19; 5. pregnant; 6. mentally or neurologically disabled patients who are considered not fit to consent to their participation in the study; 7. prior covid-19 infection. treatment sub study inclusion criteria: 1. capable of understanding and providing signed informed consent and ability to adhere to the requirements and restrictions of this protocol; 2. men and women ≥ 19 years of age unless local laws dictate otherwise; 3. english speaking; 4. must be willing to use an adequate form of contraception (or abstinence) from the time of the first dose with the imp until after the last dose of imp; 5. positive covid-19 test or presentation of clinical symptoms defined as fatigue with either fever >37.2 (oral) and/or a persistent cough. treatment sub study