Vapendavir-d5 is the deuterium labeled Vapendavir. Vapendavir (BTA798) is a potent enteroviral capsid binder (CB). Vapendavir (BTA798) possesses potent antiviral activity for enterovirus 71 (EV71) replication, with EC 50 values of 0.5-1.4 μM in different EV71 strains.