? Patients 18 years and older? Patients with a diagnosis of COVID-19 based on a compatible clinical presentation AND a positive SARS-CoV-2 PCR on a respiratory sample such as a nasopharyngeal swab, sputum, or BAL fluid? Clinical features compatible with hyperinflammation:- Hypoxia, without other explanation for hypoxia than COVID-19 OR- ferritin >2000 µg/L or doubling of serum ferritin in 20-48 hoursHypoxia is defined according to ASTCT CRS Consensus grading: grade II. [Lee DW, et al. BBMT 2019,25(4):625-638] Inclusion of patients already requiring oxygen administration prior to COVID-19 should be discussed with the study team.? Written informed consent.? Patient is capable of giving informed consent.

? Patients 18 years and older? Patients with a diagnosis of COVID-19 based on a compatible clinical presentation AND a positive SARS-CoV-2 PCR on a respiratory sample such as a nasopharyngeal swab, sputum, or BAL fluid? Clinical features compatible with hyperinflammation:- Hypoxia, without other explanation for hypoxia than COVID-19 OR- ferritin >2000 µg/L or doubling of serum ferritin in 20-48 hoursHypoxia is defined according to ASTCT CRS Consensus grading: grade II. [Lee DW, et al. BBMT 2019,25(4):625-638] Inclusion of patients already requiring oxygen administration prior to COVID-19 should be discussed with the study team.? Written informed consent.? Patient is capable of giving informed consent.