Treatment of SARS with human interferons

Effective antiviral agents are needed to treat severe acute respiratory syndrome-associated coronavirus (SARS-CoV) infection. We assessed the antiviral potential of recombinant interferons against two clinical isolates of SARS-CoV—FFM-1, from Frankfurt patients, and Hong Kong—replicated in Vero and Caco2 cells. Interferon β was five to ten times more effective in Caco2 cells. Interferon α effectively inhibited SARS-CoV replication, but with a selectivity index 50–90 times lower than that for interferon β. Interferon γ was slightly better than interferon α in Vero cell cultures, but was completely ineffective in Caco2 cell cultures. Interferon β could be useful alone or in combination with other antiviral drugs for the treatment of SARS.