To Evaluate SCTA01 Treatment of High-risk Outpatients With COVID-19

Inclusion Criteria:

1. Male or non-pregnant female adults, ≥18 years old of age at the time of randomization;
2. Participants should have at least one of COVID-19 risk factor;
3. Participants should have at least 2 COVID-19 related symptoms;
4. Has symptoms consistent with COVID-19 as determined by the investigator with onset ≤7 days before randomization;
5. First positive SARS-CoV-2 viral infection tested (PCR or antigen-based diagnostic tests) in samples collected ≤3 days prior to start of the infusion;
6. Participants are currently not hospitalized;
7. Participant (or legal authorized representative) has signed the ICF before any clinical activity related to SCTA01 trial;
8. Women with childbearing potential must agree to use effective contraceptive methods during the study period;
9. Patient should not participate in other clinical studies related to COVID-19 or SARS-CoV-2 infection.

Exclusion Criteria:

1. Have known allergies to any of the components used in the formulation of the SCTA01/placebo;
2. Participants with a history of severe anaphylaxis, such as severe anaphylactic reaction, urticaria, and angioedema;
3. Have SpO2 ≤ 93% on room air at sea level or PaO2/FiO2 < 300, respiratory rate ≥30 per minute, heart rate ≥125 per minute (FDA);
4. Require mechanical ventilation or anticipated impending need for mechanical ventilation;
5. Suspected or proven serious bacterial, fungal, viral, or other infection (besides COVID-19) that in the opinion of the investigator could constitute a risk when taking part in this study;
6. Have any serious concomitant systemic disease, condition or disorder that, in the opinion of the investigator, should preclude participation in this study;
7. Have any co-morbidity requiring surgery within <29 days, or that is considered life threatening within 29 days;
8. Have a history of previous SARS-CoV-2 infection;
9. Received convalescent plasma, COVID-19 vaccine, or anti-SARS-CoV-2 spike(S) protein targeted therapy;
10. Have participated in a clinical study involving an investigational intervention within past 30 days or 5-half lives of investigational product, whichever is longer;
11. Have received an investigational intervention for SARS-CoV-2 prophylaxis within 30 days before dosing;
12. Pregnant or lactating women;
13. Anticipated hospitalization or transfer to another medical site which is not a study site within 72 hours;
14. Participants unable to follow the protocol during the study;
15. Participants deemed inappropriate for enrollment by the investigator due to other factors.