inclusion criteria: * subject (or authorized legal representative) who can provide written informed consent before beginning any study procedure. * understand and agree to abide by the study procedures. * adult #18 years of age at the time of inclusion in the study. * confirmation of sars-cov-2 infection by a microbiological test performed before randomization, no longer than 72 hours. * severity 3-4 according to the who 7-point ordinal scale.

inclusion criteria: * subject (or authorized legal representative) who can provide written informed consent before beginning any study procedure. * understand and agree to abide by the study procedures. * adult #18 years of age at the time of inclusion in the study. * confirmation of sars-cov-2 infection by a microbiological test performed before randomization, no longer than 72 hours. * severity 3-4 according to the who 7-point ordinal scale.

inclusion criteria: - subject (or authorized legal representative) who can provide written informed consent before beginning any study procedure. - understand and agree to abide by the study procedures. - adult #18 years of age at the time of inclusion in the study. - confirmation of sars-cov-2 infection by a microbiological test performed before randomization, no longer than 72 hours. - severity 3-4 according to the who 7-point ordinal scale.

inclusion criteria: - subject (or authorized legal representative) who can provide written informed consent before beginning any study procedure. - understand and agree to abide by the study procedures. - adult #18 years of age at the time of inclusion in the study. - confirmation of sars-cov-2 infection by a microbiological test performed before randomization, no longer than 72 hours. - severity 3-4 according to the who 7-point ordinal scale.