ABSTRACT
Recent studies have identified an association between perturbed type I interferon (IFN) responses and the severity of coronavirus disease 2019 (COVID-19). IFNα intervention may normalize the dysregulated innate immunity of COVID-19. However, details regarding its utilization and therapeutic evidence have yet to be systematically evaluated. The aim of this comprehensive review was to summarize the current utilization of IFNα for COVID-19 treatment and to explore the evidence on safety and efficacy. A comprehensive review of clinical studies in the literature prior to December 1st, 2021, was performed to identify the current utilization of IFNα, which included details on the route of administration, the number of patients who received the treatment, the severity at the initiation of treatment, age range, the time from the onset of symptoms to treatment, dose, frequency, and duration as well as safety and efficacy. Encouragingly, no evidence was found against the safety of IFNα treatment for COVID-19. Early intervention, either within five days from the onset of symptoms or at hospital admission, confers better clinical outcomes, whereas late intervention may result in prolonged hospitalization.