inclusion criteria: * willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. * age ≥18 years * evidence of sars-cov-2 infection by pcr test of naso-/oro-pharyngeal swab or tracheal aspirate sample within 14 days of randomization * peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening * evidence of infiltrates on chest radiography * females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.

inclusion criteria: * willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. * age ≥18 years * evidence of sars-cov-2 infection by pcr test of naso-/oro-pharyngeal swab or tracheal aspirate sample within 14 days of randomization * peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening * evidence of infiltrates on chest radiography * females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.

inclusion criteria: - willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. - age ≥18 years - evidence of sars-cov-2 infection by pcr test of naso-/oro-pharyngeal swab or tracheal aspirate sample within 14 days of randomization - peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening - evidence of infiltrates on chest radiography - females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.

inclusion criteria: - willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. - age ≥18 years - evidence of sars-cov-2 infection by pcr test of naso-/oro-pharyngeal swab or tracheal aspirate sample within 14 days of randomization - peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening - evidence of infiltrates on chest radiography - females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.

inclusion criteria: - willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. - age ≥18 years - evidence of sars-cov-2 infection by pcr test of naso-/oro-pharyngeal swab or tracheal aspirate sample within 7 days of randomization - peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening - evidence of infiltrates on chest radiography - females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.

inclusion criteria: - willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. - age ≥18 years - evidence of sars-cov-2 infection by pcr test of naso-/oro-pharyngeal swab or tracheal aspirate sample within 7 days of randomization - peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening - evidence of infiltrates on chest radiography - females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.

inclusion criteria: - willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. - age ≥18 years - evidence of sars-cov-2 infection by pcr test of nasopharyngeal swab sample within 7 days of randomization - peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening - evidence of infiltrates on chest radiography - females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.

inclusion criteria: - willing and able to provide written informed consent prior to performing study procedures or have a legally authorized representative available to do so. - age ≥18 years - evidence of sars-cov-2 infection by pcr test of nasopharyngeal swab sample within 7 days of randomization - peripheral capillary oxygen saturation (spo2) ≤ 94% on room air or requiring supplemental oxygen, non-invasive or invasive mechanical ventilation at screening - evidence of infiltrates on chest radiography - females of childbearing age and males, must be willing to practice an effective contraceptive method or remain abstinent during the study period.