Relenza® is GlaxoSmithKline's brand of zanamivir, a first in-class antiviral drug for the treatment and prevention of influenza. Zanamivir was licensed to GlaxoSmithKline by Biota in 1990 and launched worldwide in 1999.
Relenza is delivered directly to the primary site of infection on the lungs, using a Disk Inhaler™ device. The drug works by destroying an enzyme, neuraminidase, on the surface of the virus, essential for the multiplication and spread of influenza. Relenza is not a vaccine.