MVA-BN® (Modified Vaccinia Ankara - Bavarian Nordic) is a proprietary and patented vaccine platform technology of Bavarian Nordic. MVA-BN is a robust and adaptable platform suitable for addressing a wide variety of infectious diseases and cancers. It is a further attenuated version of the Modified Vaccinia Ankara (MVA) virus, which is a highly attenuated strain of the poxvirus Chorioallantois Vaccinia virus Ankara (CVA).

MVA-BN® is approved as a smallpox vaccine in Canada and the EU (under the trade names IMVAMUNE® and IMVANEX® respectively).

A major advantage of MVA-BN is the virus’ inability to replicate in a vaccinated individual, in contrast to the original smallpox vaccines. The replication cycle is blocked at a very late stage, which ensures that new viruses are not generated and released in the body. This means that the virus cannot spread in a vaccinated person, which likely contributes to the favorable safety profile observed for MVA-BN-based vaccines in more than a dozen clinical studies conducted by Bavarian Nordic. More than 7,600 individuals, nearly 1,000 of whom are immunocompromised, have been vaccinated with MVA-BN-based vaccines, showing the platform displays high immunogenicity and a favorable safety profile.

In terms of efficacy, MVA-BN induces strong cellular activity (CTL) as well as humoral (antibody) immune response and has demonstrated an ability to stimulate a response even in individuals with pre-existing immunity against vaccinia. MVA-BN homologous vaccines consist of an initial prime dose to activate the immune system, followed by a second booster dose of the same vaccine. These are simpler and easier to develop and license than heterologous vaccines, which use different types of vaccine technologies.