* moderate to severe hypoxic respiratory failure requiring supplemental oxygen at rest, mechanical ventilation, ecmo, or any other noninvasive ventilation modality. * crp \>15 mg/l or d-dimer \> 0.75 µg/ml. * estimated glomerular filtration rate (egfr) \< 40 ml/min/1.73m2, or requiring dialysis. * ast/alt \> 3-times uln, or total bilirubin \> 1.5 times uln (except if due to gilbert's syndrome). * pregnancy or breastfeeding. * use of systemic corticosteroids or immunomodulant within 4 weeks prior to screening. * receipt of an investigational agent or investigational use of a licensed agent within 16 weeks prior to screening. * hiv infection or underlying history of known or unknown primary or acquired immunodeficiency associated with lymphopenia and/or recurrent opportunistic infections. * autoimmune disease requiring systemic treatment except for vitiligo or endocrine disease (such as diabetes, thyroid disease, and adrenal disease) controlled by replacement therapy. * malignancy requiring treatment 1 year prior to screening.

* moderate to severe hypoxic respiratory failure requiring supplemental oxygen at rest, mechanical ventilation, ecmo, or any other noninvasive ventilation modality. * crp \>15 mg/l or d-dimer \> 0.75 µg/ml. * estimated glomerular filtration rate (egfr) \< 40 ml/min/1.73m2, or requiring dialysis. * ast/alt \> 3-times uln, or total bilirubin \> 1.5 times uln (except if due to gilbert's syndrome). * pregnancy or breastfeeding. * use of systemic corticosteroids or immunomodulant within 4 weeks prior to screening. * receipt of an investigational agent or investigational use of a licensed agent within 16 weeks prior to screening. * hiv infection or underlying history of known or unknown primary or acquired immunodeficiency associated with lymphopenia and/or recurrent opportunistic infections. * autoimmune disease requiring systemic treatment except for vitiligo or endocrine disease (such as diabetes, thyroid disease, and adrenal disease) controlled by replacement therapy. * malignancy requiring treatment 1 year prior to screening.

- moderate to severe hypoxic respiratory failure requiring supplemental oxygen at rest, mechanical ventilation, ecmo, or any other noninvasive ventilation modality. - crp >15 mg/l or d-dimer > 0.75 µg/ml. - estimated glomerular filtration rate (egfr) < 40 ml/min/1.73m2, or requiring dialysis. - ast/alt > 3-times uln, or total bilirubin > 1.5 times uln (except if due to gilbert's syndrome). - pregnancy or breastfeeding. - use of systemic corticosteroids or immunomodulant within 4 weeks prior to screening. - receipt of an investigational agent or investigational use of a licensed agent within 16 weeks prior to screening. - hiv infection or underlying history of known or unknown primary or acquired immunodeficiency associated with lymphopenia and/or recurrent opportunistic infections. - autoimmune disease requiring systemic treatment except for vitiligo or endocrine disease (such as diabetes, thyroid disease, and adrenal disease) controlled by replacement therapy. - malignancy requiring treatment 1 year prior to screening.

- moderate to severe hypoxic respiratory failure requiring supplemental oxygen at rest, mechanical ventilation, ecmo, or any other noninvasive ventilation modality. - crp >15 mg/l or d-dimer > 0.75 µg/ml. - estimated glomerular filtration rate (egfr) < 40 ml/min/1.73m2, or requiring dialysis. - ast/alt > 3-times uln, or total bilirubin > 1.5 times uln (except if due to gilbert's syndrome). - pregnancy or breastfeeding. - use of systemic corticosteroids or immunomodulant within 4 weeks prior to screening. - receipt of an investigational agent or investigational use of a licensed agent within 16 weeks prior to screening. - hiv infection or underlying history of known or unknown primary or acquired immunodeficiency associated with lymphopenia and/or recurrent opportunistic infections. - autoimmune disease requiring systemic treatment except for vitiligo or endocrine disease (such as diabetes, thyroid disease, and adrenal disease) controlled by replacement therapy. - malignancy requiring treatment 1 year prior to screening.

- moderate to severe hypoxic respiratory failure requiring supplemental oxygen at rest, mechanical ventilation, ecmo, or any other noninvasive ventilation modality. - crp >15 mg/l or d-dimer > 0.75 µg/ml. - estimated glomerular filtration rate (egfr) < 40 ml/min/1.73m2, or requiring dialysis. - ast/alt > 3-times uln, total bilirubin > 1.5 times uln (except if due to gilbert's syndrome). - pregnancy or breastfeeding. - use of systemic corticosteroids or immunomodulant within 4 weeks prior to screening. - receipt of an investigational agent or investigational use of a licensed agent within 16 weeks prior to screening. - hiv infection or underlying history of known or unknown primary or acquired immunodeficiency associated with lymphopenia and/or recurrent opportunistic infections. - autoimmune disease requiring systemic treatment except for vitiligo or endocrine disease (such as diabetes, thyroid disease, and adrenal disease) controlled by replacement therapy. - malignancy requiring treatment 1 year prior to screening.

- moderate to severe hypoxic respiratory failure requiring supplemental oxygen at rest, mechanical ventilation, ecmo, or any other noninvasive ventilation modality. - crp >15 mg/l or d-dimer > 0.75 µg/ml. - estimated glomerular filtration rate (egfr) < 40 ml/min/1.73m2, or requiring dialysis. - ast/alt > 3-times uln, total bilirubin > 1.5 times uln (except if due to gilbert's syndrome). - pregnancy or breastfeeding. - use of systemic corticosteroids or immunomodulant within 4 weeks prior to screening. - receipt of an investigational agent or investigational use of a licensed agent within 16 weeks prior to screening. - hiv infection or underlying history of known or unknown primary or acquired immunodeficiency associated with lymphopenia and/or recurrent opportunistic infections. - autoimmune disease requiring systemic treatment except for vitiligo or endocrine disease (such as diabetes, thyroid disease, and adrenal disease) controlled by replacement therapy. - malignancy requiring treatment 1 year prior to screening.