American researchers published positive results with GS-5806, a novel antiviral that inhibits the activity of respiratory syncytial virus (RSV). The orally administered fusion inhibitor was effective during a placebo-controlled challenge study where healthy adults were experimentally infected with the well-characterized Memphis-37b strain.
John DeVincenzo, associated with the Le Bonheur Children's Hospital (Memphis, TN, USA), and colleagues found that administration of GS-5086 at 2-5 days after infection prevented mucus production, respiratory symptoms, and subsequent development of high viral loads. Peak viral loads were 3-4 logs lower in treated participants. No signs of toxicity were observed. This study is a major step forward towards a treatment for patients with RSV infection.