inclusion criteria: * male or female ≥ 18 years of age, * using contraceptive consistent with local regulations regarding the methods of contraception for those participating in clinical studies * willing and able to provide written informed consent (or provided by legally acceptable representative if he/she is present and if in line with local regulations), * admitted in icu within 48 hours before randomization for covid-19 related respiratory failure. (icu or equivalent medical structure according to country specificities e.g., acute respiratory care unit, high dependency care unit if they can provide: continuous iv infusion,continuous ecg, respiratory rate, percutaneous oxygen saturation screen monitoring, high flow nasal oxygen) * not requiring immediate (within 24-36 hours) invasive mechanical ventilation according to investigator's judgment, * confirmed pneumoniae due to sars-cov-2, laboratory-confirmed sars-cov-2 infection as determined by rt-pcr (in nasopharynx or throat samples) or other commercial or public health assay in any specimen, performed within 2 weeks prior to randomization, * acute respiratory failure requiring oxygen support (≥ 5l/min) to achieve a transcutaneous oxygen saturation \> 94%, * estimated glomerular filtration rate (egfr) \> 50 ml/min/1.73m2 by the ckd-epi (chronic kidney disease - epidemiology collaboration) equation.

inclusion criteria: * male or female ≥ 18 years of age, * using contraceptive consistent with local regulations regarding the methods of contraception for those participating in clinical studies * willing and able to provide written informed consent (or provided by legally acceptable representative if he/she is present and if in line with local regulations), * admitted in icu within 48 hours before randomization for covid-19 related respiratory failure. (icu or equivalent medical structure according to country specificities e.g., acute respiratory care unit, high dependency care unit if they can provide: continuous iv infusion,continuous ecg, respiratory rate, percutaneous oxygen saturation screen monitoring, high flow nasal oxygen) * not requiring immediate (within 24-36 hours) invasive mechanical ventilation according to investigator's judgment, * confirmed pneumoniae due to sars-cov-2, laboratory-confirmed sars-cov-2 infection as determined by rt-pcr (in nasopharynx or throat samples) or other commercial or public health assay in any specimen, performed within 2 weeks prior to randomization, * acute respiratory failure requiring oxygen support (≥ 5l/min) to achieve a transcutaneous oxygen saturation \> 94%, * estimated glomerular filtration rate (egfr) \> 50 ml/min/1.73m2 by the ckd-epi (chronic kidney disease - epidemiology collaboration) equation.

inclusion criteria: male or female ≥ 18 years of age, using contraceptive consistent with local regulations regarding the methods of contraception for those participating in clinical studies willing and able to provide written informed consent (or provided by legally acceptable representative if he/she is present and if in line with local regulations), admitted in icu within 48 hours before randomization for covid-19 related respiratory failure. (icu or equivalent medical structure according to country specificities e.g., acute respiratory care unit, high dependency care unit if they can provide: continuous iv infusion,continuous ecg, respiratory rate, percutaneous oxygen saturation screen monitoring, high flow nasal oxygen) not requiring immediate (within 24-36 hours) invasive mechanical ventilation according to investigator's judgment, confirmed pneumoniae due to sars-cov-2, laboratory-confirmed sars-cov-2 infection as determined by rt-pcr (in nasopharynx or throat samples) or other commercial or public health assay in any specimen, performed within 2 weeks prior to randomization, acute respiratory failure requiring oxygen support (≥ 5l/min) to achieve a transcutaneous oxygen saturation > 94%, estimated glomerular filtration rate (egfr) > 50 ml/min/1.73m2 by the ckd-epi (chronic kidney disease - epidemiology collaboration) equation.

inclusion criteria: male or female ≥ 18 years of age, using contraceptive consistent with local regulations regarding the methods of contraception for those participating in clinical studies willing and able to provide written informed consent (or provided by legally acceptable representative if he/she is present and if in line with local regulations), admitted in icu within 48 hours before randomization for covid-19 related respiratory failure. (icu or equivalent medical structure according to country specificities e.g., acute respiratory care unit, high dependency care unit if they can provide: continuous iv infusion,continuous ecg, respiratory rate, percutaneous oxygen saturation screen monitoring, high flow nasal oxygen) not requiring immediate (within 24-36 hours) invasive mechanical ventilation according to investigator's judgment, confirmed pneumoniae due to sars-cov-2, laboratory-confirmed sars-cov-2 infection as determined by rt-pcr (in nasopharynx or throat samples) or other commercial or public health assay in any specimen, performed within 2 weeks prior to randomization, acute respiratory failure requiring oxygen support (≥ 5l/min) to achieve a transcutaneous oxygen saturation > 94%, estimated glomerular filtration rate (egfr) > 50 ml/min/1.73m2 by the ckd-epi (chronic kidney disease - epidemiology collaboration) equation.