Interferon-β 1a inhibits SARS-CoV-2 in vitro when administered after virus infection

The ongoing COVID-19 pandemic has forced the clinical and scientific community to try drug repurposing of existing antiviral agents as a quick option against SARS-CoV-2. Under this scenario, the interferon-β 1a (IFN-β 1a) whose antiviral potential is already known, and is a drug currently used in the clinical management of multiple sclerosis, may represent as a potential candidate. In this report, we demonstrate that IFN-β 1a was highly effective in inhibiting in vitro SARS-CoV-2 replication at clinically achievable concentration when administered after virus infection.