According to some recent evidence, some patients with COVID-19 may develop secondary haemophagocytic lymphohistiocytosis, an underrecognized hyperinflammatory syndrome characterized by a fulminant and fatal hypercytokinaemia, with development of ARDS and multiorgan failure [46,47,67]. Consequently, immunosuppressive and/or immunomodulatory therapies have been proposed to contrast COVID-19–associated hyperinflammation.