An Observational Study in Patients With Mild to Moderate COVID-19

Inclusion Criteria: * Participants who have a positive SARS-CoV-2 test result. * Participants who have one or more mild or moderate COVID-19 symptoms. * Participants who have one or more of the following requirements: ≤7 days from the first positive test for SARS-COV-2 virus infection to Day 1; ≤5 days from the first onset of COVID-19 symptoms to Day 1. * Participants who satisfy one or more than one of the following high risks for progression to severe COVID-19, including death. * Participants who understand and agree to comply with planned study procedures. * Participants or legally authorized representatives can give written informed consent approved by the Ethical Review Board governing the site. * Capable of giving signed informed consent, including of compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol. Exclusion Criteria: * Participants who are judged by the investigator as likely to progress to severe/critical COVID-19 prior to randomization. * Participants who have SpO2≤93% on room air at sea level or PaO2/FiO2≤ 300, or respiratory rate ≥30 per minute. * Participants who require mechanical ventilation or anticipated impending need for mechanical ventilation. * Participants who have received or plan to receive a SARS-CoV-2 monoclonal antibody treatment or prevention, or antiviral treatment (including the investigational treatment). * Participants who have received convalescent COVID-19 plasma treatment.