Positive CHMP opinion for including Mpox real-world effectiveness data in European Marketing Authorization for smallpox and Mpox vaccine.- Bavarian Nordic

In the absence of real-world data before the 2022 outbreak, the European marketing authorization of MVA-BN, granted in 2013 for smallpox prevention and extended in 2022 to include mpox, was based on efficacy data in non-human primates and immunogenicity data from numerous studies involving more than 4,000 healthy and immune-compromised individuals. These data demonstrated that MVA-BN had a favorable safety profile and induced immune responses that were non-inferior when compared to traditional smallpox vaccines, which are known to confer cross-protection against mpox and other orthopoxviruses.

After a systematic review and analysis of data from real-world observational studies conducted in vaccine-eligible individuals and published after the onset of the global mpox outbreak in 2022, Bavarian Nordic submitted an application to EMA in late 2023 for a type II variation, representing a major change to the marketing authorization for MVA-BN.

In the real-world studies, vaccine effectiveness against mpox disease was demonstrated at least 14 days after vaccination, with adjusted vaccine effectiveness estimates ranging from 35% (95% CI, -2-59) to 89% (95% CI, 76-95) after one MVA-BN dose and from 66% (95% CI, 47-78) to 90% (95% CI, 86-92) after two MVA-BN doses. Furthermore, in a surveillance study, MVA-BN was shown to reduce the risks of mpox-related hospitalization. Compared with unvaccinated mpox patients, the odds of hospitalization were 0.27 (95% CI, 0.08-0.65) after one MVA-BN dose, and 0.20 (95% CI, 0.01-0.90) after two MVA-BN doses. The estimated relative risk reduction was 73% after one MVA-BN dose and 80% after two MVA-BN doses.

“The 2022 global mpox outbreak provided an opportunity to assess the effectiveness of our vaccine in at-risk populations across different geographies, both before and after exposure to the mpox virus, and we are pleased to receive the recommendation to include real-life data in our marketing authorization in Europe, which confirm a high effectiveness of up to 90% after two doses of the vaccine as recommended by the authorities. It is furthermore encouraging that data show the vaccine to significantly reduce the risk of hospitalizations, thus confirming our vaccine as an important and versatile tool in the fight against mpox globally,” said Paul Chaplin, President and Chief Executive Officer of Bavarian Nordic.