Patients 18 years and older SARS-CoV-2 infection confirmed by PCR in any specimen < 9 days prior to randomization Admitted to the hospital ward or the ICU due to COVID-19 SpO2 ≤ 94% on room air OR oxygen demand OR breathing support Written informed consent obtained

Patients 18 years and older SARS-CoV-2 infection confirmed by PCR in any specimen < 9 days prior to randomization Admitted to the hospital ward or the ICU due to COVID-19 SpO2 ≤ 94% on room air OR oxygen demand OR breathing support Written informed consent obtained

Patients 18 years and older SARS-CoV-2 infection confirmed by PCR in any specimen < 72 hours prior to randomization Admitted to the hospital ward or the ICU due to COVID-19 SpO2 ≤ 94% on room air OR oxygen demand OR breathing support Written informed consent obtained

Patients 18 years and older SARS-CoV-2 infection confirmed by PCR in any specimen < 72 hours prior to randomization Admitted to the hospital ward or the ICU due to COVID-19 SpO2 ≤ 94% on room air OR oxygen demand OR breathing support Written informed consent obtained