inclusion criteria: 1. part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who agree to be monitored daily for at least 7 days after randomization and who accept continuing to be assessed for the study procedures. 2. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia.

inclusion criteria: 1. part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who agree to be monitored daily for at least 7 days after randomization and who accept continuing to be assessed for the study procedures. 2. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia.

inclusion criteria: part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who agree to be monitored daily for at least 7 days after randomization and who accept continuing to be assessed for the study procedures. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia.

inclusion criteria: part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who agree to be monitored daily for at least 7 days after randomization and who accept continuing to be assessed for the study procedures. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia.

inclusion criteria: 1. part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who agree to be monitored daily for at least 7 days after randomization and who accept continuing to be assessed for the study procedures. 2. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia.

inclusion criteria: 1. part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who agree to be monitored daily for at least 7 days after randomization and who accept continuing to be assessed for the study procedures. 2. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia.

inclusion criteria: 1. part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who are expected to remain hospitalized or in an inpatient setting for at least 7 days after randomization and who accept continuing to be assessed for the study procedures (home or outpatient unit) for up to 6 months in case of hospital discharge. 2. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who are not planned to be hospitalized. 3. patients who had diarrhea, defined as at least 3 watery stools in the last 24 hours, prior to randomization.

inclusion criteria: 1. part 1 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who are expected to remain hospitalized or in an inpatient setting for at least 7 days after randomization and who accept continuing to be assessed for the study procedures (home or outpatient unit) for up to 6 months in case of hospital discharge. 2. part 2 only, patients with a primary diagnosis of covid-19, with or without pneumonia, who are not planned to be hospitalized. 3. patients who had diarrhea, defined as at least 3 watery stools in the last 24 hours, prior to randomization.