Convalescent Plasma (PC) and Human Intravenous Anti-COVID-19 Immunoglobulin (IV Anti COVID-19 IgG) in Patients Hospitalized for COVID-19.

Inclusion Criteria:

1. Obtaining the informed written consent before carrying out the study procedures, by the patients.
2. Adult patients ≥18 years at the time of recruitment for the study.
3. Patients with laboratory-confirmed SARS-CoV-2 infection as determined by polymerase chain reaction on nasal/oropharyngeal swabs or any other relevant specimen <72 hours before randomization.

4. Patients requiring hospitalization for COVID-19 without mechanical ventilation (invasive or non-invasive, including an oxygen mask with reserve bag) and at least one of the following:

   1. Radiographic evidence of pulmonary infiltrates by images (chest radiography, computed tomography, etc.),
   2. Clinical evaluation (evidence of rales/crackles on examination) and oxygen saturation ≤ 94% in ambient air requiring supplemental oxygen.
5. Patient with no more than 72 hours (3 days) of hospitalization prior to the administration of PC treatment (except the days after initial hospital admission for other reasons and prior to COVID-19 infection).
6. Patients who do not have more than 10 days between the onset of symptoms (fever or cough) and the day of administration of treatment or the demonstration of the absence of anti-SARS-CoV-2 antibodies (patients with more than 10 days of symptoms they can only be included if a negative antibody result has been confirmed).

Exclusion Criteria:

1. Patient in a state of pregnancy.
2. Require mechanical ventilation (invasive or non-invasive, including oxygen mask with reserve bag) on examination.
3. Participation in any other clinical trial of an experimental treatment for COVID-19.
4. At the discretion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, regardless of the provision of treatments.
5. Any incompatibility or allergy to the administration of plasma of human origin.
6. Severe chronic kidney disease in stage 4 or requiring dialysis (that is, glomerular filtration rate <30).
7. Any condition that in the investigator's opinion limits participation in the study.