IFNB1 and COVID-19: IFN therapy has also been studied recently in COVID-19, with early subcutaneous IFN-β proving effective at reducing severe outcomes, and early subcutaneous IFN-β and IFN-λ both proving effective at speeding up virus clearance when administered in the first 7 days from symptom onset (Hung et al., 2020; Feld et al., 2021).