The study showed that a single vaccination of Imvamune could protect a variety of immune suppressed animals on the same day as a lethal challenge with Ectromelia virus; a natural poxvirus infection of mice that closely models smallpox infection in humans.
Some of these mice were so immune suppressed that vaccination with a traditional smallpox vaccine (Dryvax) led to the death of the animals prior to any challenge with Ectromelia. Not only was Imvamune therefore shown to be safer than traditional smallpox vaccines, but a single vaccination with Imvamune given up to three days post the lethal challenge with Ectromelia protected the mice. According to the company, this is the first therapeutic or post-exposure protection, demonstrated for a smallpox vaccine in a relevant animal model.
Anders Hedegaard, president and CEO of Bavarian Nordic, said: “With Imvamune we can offer a safer vaccine and a solid protection both before and after exposure. No other smallpox vaccine has shown to offer these important features.”