Early in the COVID-19 pandemic, several groups of scientists proposed IFN- as a potential therapy for SARS-CoV-2 infection (O’Brien et al., Clinical Infectious Diseases, 2020; Prokunina-Olsson et al., Journal of Experimental Medicine, 2020). That suggestion was based on evidence that the IFN- family provides important first-line immunological defense against viral respiratory tract infections and data indicating that SARS-CoV-2 induces weak expression of IFNs. There are no licensed IFN- therapeutics, however, pegylated-interferon lambda 1, which was shown to be safe and effective in testing among >3,000 patients with chronic viral hepatitis infections, is available as an investigational agent through Eiger Biopharmaceuticals. Several phase 2 clinical trials have been launched to assess the safety and efficacy of pegylated-IFN-1 for treatment or prevention of SARS-CoV-2 / COVID-19. Findings from two trials are now available. [READ MORE]