Hazard Characterization of Modified Vaccinia Virus Ankara Vector: What Are the Knowledge Gaps?

Okeke, Malachy I.; Okoli, Arinze S.; Diaz, Diana; Offor, Collins; Oludotun, Taiwo G.; Tryland, Morten; Bøhn, Thomas; Moens, Ugo

The development and optimization of MVA as a smallpox vaccine continued post smallpox eradication. This in part is driven by the concern that the smallpox virus may re-emerge, either due to accidental escape from containment or due to bioterrorism. Hence, there is a public health need to optimize MVA as an effective but safer alternative to multiplication competent smallpox vaccines. The European Medicines Agency (EMA) has registered Imvanex ® (MVA-BN), as a smallpox vaccine. MVA-BN is a single clone derived from MVA-584 following six rounds of plaque purification [56] . Currently, MVA-BN is the most host restricted MVA variant in vitro as well as the most attenuated in vivo [56] .