zelicapavir

Zelicapavir is an oral, small molecule antiviral drug developed by Enanta Pharmaceuticals for the treatment of respiratory syncytial virus (RSV) infections, including both RSV-A and RSV-B. It acts as a nanomolar inhibitor of the RSV nucleoprotein (N-protein), directly targeting the virus's replication machinery rather than preventing viral entry like fusion inhibitors. This mechanism disrupts viral replication and provides a high barrier to resistance, maintaining potency against various clinical isolates and variants resistant to other mechanisms. Zelicapavir has demonstrated favorable safety and pharmacokinetic profiles in clinical studies, with robust antiviral effects observed in Phase II trials in both adult and pediatric populations. The drug has received Fast Track designation from the FDA for its development in RSV infection[1][2][4][5][6][7][8].