Part 1 1. Age ≥18 years and ≤79 years at the time of obtaining informed consent. 2. Participants must: a. have positive SARS-CoV-2 result (any validated test, e.g. RT-PCR [performed on an appropriate specimen, e.g. respiratory tract sample]) b. AND be hospitalized due to diagnosis of pneumonia (chest X-ray or computerized tomography [CT] scan consistent with COVID-19) c. AND be developing new onset of oxygenation impairment requiring any of the following - high-flow oxygen (≥15L/min) - non-invasive ventilation (NIV, CPAP, BIPAP) - mechanical ventilation ≤48h prior to dose d. AND have increased biological markers of systemic inflammation (either CRP >ULN or serum ferritin >ULN). 3. No gender restriction. 4. Female participants must meet and agree to abide by the contraceptive criteria detailed in the protocol. 5. Capable of giving written informed consent. If participants are not capable of giving written informed consent, alternative consent procedures will be followed. Part 2 1. Age 70 years or above at the time of obtaining informed consent. 2. Participants must: a. have positive SARS-CoV-2 result (any validated test, e.g. RT-PCR [performed on an appropriate specimen, e.g. respiratory tract sample]) b. AND be hospitalized due to diagnosis of pneumonia (chest X-ray or computerized tomography [CT] scan consistent with COVID-19) c. AND be developing new onset of oxygenation impairment requiring any of the following - high-flow oxygen (≥15L/min) - non-invasive ventilation (NIV, CPAP, BIPAP) - mechanical ventilation ≤48h prior to dose d. AND have increased biological markers of systemic inflammation (either CRP >ULN or serum ferritin >ULN). 3. No gender restriction 4. Capable of giving written informed consent. If participants are not capable of giving written informed consent, alternative consent procedures will be followed.

Part 1 1. Age ≥18 years and ≤79 years at the time of obtaining informed consent. 2. Participants must: a. have positive SARS-CoV-2 result (any validated test, e.g. RT-PCR [performed on an appropriate specimen, e.g. respiratory tract sample]) b. AND be hospitalized due to diagnosis of pneumonia (chest X-ray or computerized tomography [CT] scan consistent with COVID-19) c. AND be developing new onset of oxygenation impairment requiring any of the following - high-flow oxygen (≥15L/min) - non-invasive ventilation (NIV, CPAP, BIPAP) - mechanical ventilation ≤48h prior to dose d. AND have increased biological markers of systemic inflammation (either CRP >ULN or serum ferritin >ULN). 3. No gender restriction. 4. Female participants must meet and agree to abide by the contraceptive criteria detailed in the protocol. 5. Capable of giving written informed consent. If participants are not capable of giving written informed consent, alternative consent procedures will be followed. Part 2 1. Age 70 years or above at the time of obtaining informed consent. 2. Participants must: a. have positive SARS-CoV-2 result (any validated test, e.g. RT-PCR [performed on an appropriate specimen, e.g. respiratory tract sample]) b. AND be hospitalized due to diagnosis of pneumonia (chest X-ray or computerized tomography [CT] scan consistent with COVID-19) c. AND be developing new onset of oxygenation impairment requiring any of the following - high-flow oxygen (≥15L/min) - non-invasive ventilation (NIV, CPAP, BIPAP) - mechanical ventilation ≤48h prior to dose d. AND have increased biological markers of systemic inflammation (either CRP >ULN or serum ferritin >ULN). 3. No gender restriction 4. Capable of giving written informed consent. If participants are not capable of giving written informed consent, alternative consent procedures will be followed.