AGE AND RISK FACTORS 1. Participant must be aged 12 years or older at time of consent AND at high risk of progression of COVID-19 based on the presence of one or more of the following risk factors: a. For 12-17 years old: diabetes, obesity (BMI ≥85th percentile for age/gender based on CDC growth charts), chronic kidney disease (e.g. eGFR <60), sicklecell disease, congenital heart disease, neurodevelopmental disorders, chronic lung diseases (i.e. chronic obstructive pulmonary disease, moderate to severe asthma requiring steroids, interstitial lung disease, cystic fibrosis, and pulmonary hypertension), immunosuppressive disease or immunosuppressive medications, or chronic liver disease b. For 18-54 years old: diabetes (requiring medication), obesity (BMI ≥ 30, chronic kidney disease (i.e., eGFR <60 by MDRD), congenital heart disease, congestive heart failure (NYHA class II or more), chronic lung diseases (i.e. chronic obstructive pulmonary disease, moderate to severe asthma requiring steroids, interstitial lung disease, cystic fibrosis, and pulmonary hypertension), sickle cell disease, neurodevelopmental disorders, immunosuppressive disease or receiving immunosuppressive medications, or chronic liver disease OR 2. Participant ≥ 55 years old, irrespective of co-morbidities TYPE OF PARTICIPANT AND DISEASE CHARACTERISTICS 3. Participants who have a positive SARS-CoV-2 test result within 7 days of randomization (by any validated diagnostic test e.g. RT-PCR, antigen based testing on any specimen type) AND 4. Oxygen saturation ≥94% on room air AND 5. Have symptoms of COVID-19 defined by one or more of the following: fever, chills, cough, sore throat, malaise, headache, joint or muscle pain, change in smell or taste, vomiting, diarrhea, shortness of breath on exertion AND 6. Participant to be dosed less than or equal to 7 days from onset of symptoms to dosing day (D1) SEX AND CONTRACEPTIVE/BARRIER REQUIREMENTS 7. No gender restrictions 8. Female participants must meet and agree to abide by the following contraceptive criteria. Contraception use by women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies. A female participant is eligible to participate if she is not pregnant or breastfeeding, and one of the following conditions applies: a. Is a woman of non-childbearing potential (WONCBP). OR b. Is a WOCBP and using a contraceptive method that is highly effective, with a failure rate of <1%, during the study intervention period and for up to 24 weeks after the last dose of study intervention. The investigator should evaluate potential for contraceptive method failure (e.g., noncompliance, recently initiated) in relationship to the first dose of study intervention. A WOCBP must have a negative highly sensitive pregnancy test (urine or serum as required by local regulations) before the first dose of study intervention. -If a urine test cannot be confirmed as negative (e.g., an ambiguous result), a serum pregnancy test is required. In such cases, the participant must be excluded from participation if the serum pregnancy result is positive. INFORMED CONSENT 9. Capable of giving signed informed consent. OR 10. If participants are not capable of giving written informed consent, alternative consent procedures will be followed as defined in Section 10.1.3 of protocol. OR 11. Participants <18 years old will be required to sign an assent form in addition to a parent or guardian signing the informed consent.

AGE AND RISK FACTORS 1. Participant must be aged 12 years or older at time of consent AND at high risk of progression of COVID-19 based on the presence of one or more of the following risk factors: a. For 12-17 years old: diabetes, obesity (BMI ≥85th percentile for age/gender based on CDC growth charts), chronic kidney disease (e.g. eGFR <60), sicklecell disease, congenital heart disease, neurodevelopmental disorders, chronic lung diseases (i.e. chronic obstructive pulmonary disease, moderate to severe asthma requiring steroids, interstitial lung disease, cystic fibrosis, and pulmonary hypertension), immunosuppressive disease or immunosuppressive medications, or chronic liver disease b. For 18-54 years old: diabetes (requiring medication), obesity (BMI ≥ 30, chronic kidney disease (i.e., eGFR <60 by MDRD), congenital heart disease, congestive heart failure (NYHA class II or more), chronic lung diseases (i.e. chronic obstructive pulmonary disease, moderate to severe asthma requiring steroids, interstitial lung disease, cystic fibrosis, and pulmonary hypertension), sickle cell disease, neurodevelopmental disorders, immunosuppressive disease or receiving immunosuppressive medications, or chronic liver disease OR 2. Participant ≥ 55 years old, irrespective of co-morbidities TYPE OF PARTICIPANT AND DISEASE CHARACTERISTICS 3. Participants who have a positive SARS-CoV-2 test result within 7 days of randomization (by any validated diagnostic test e.g. RT-PCR, antigen based testing on any specimen type) AND 4. Oxygen saturation ≥94% on room air AND 5. Have symptoms of COVID-19 defined by one or more of the following: fever, chills, cough, sore throat, malaise, headache, joint or muscle pain, change in smell or taste, vomiting, diarrhea, shortness of breath on exertion AND 6. Participant to be dosed less than or equal to 7 days from onset of symptoms to dosing day (D1) SEX AND CONTRACEPTIVE/BARRIER REQUIREMENTS 7. No gender restrictions 8. Female participants must meet and agree to abide by the following contraceptive criteria. Contraception use by women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies. A female participant is eligible to participate if she is not pregnant or breastfeeding, and one of the following conditions applies: a. Is a woman of non-childbearing potential (WONCBP). OR b. Is a WOCBP and using a contraceptive method that is highly effective, with a failure rate of <1%, during the study intervention period and for up to 24 weeks after the last dose of study intervention. The investigator should evaluate potential for contraceptive method failure (e.g., noncompliance, recently initiated) in relationship to the first dose of study intervention. A WOCBP must have a negative highly sensitive pregnancy test (urine or serum as required by local regulations) before the first dose of study intervention. -If a urine test cannot be confirmed as negative (e.g., an ambiguous result), a serum pregnancy test is required. In such cases, the participant must be excluded from participation if the serum pregnancy result is positive. INFORMED CONSENT 9. Capable of giving signed informed consent. OR 10. If participants are not capable of giving written informed consent, alternative consent procedures will be followed as defined in Section 10.1.3 of protocol. OR 11. Participants <18 years old will be required to sign an assent form in addition to a parent or guardian signing the informed consent.