Relatively selective COX-2 inhibitors (e.g., celecoxib, etoricoxib) (28) may reduce pro-inflammatory cytokine levels, as shown in mice with influenza A infection (TNF-α, G-CSF, and IL-6) (29) and in hospitalized COVID-19 patients (IL-6) (19, 30). Here, IL6 is linked to COVID-19.