MVA-BN RSV is our product candidate for the prevention of RSV (Respiratory Syncytial Virus). The vaccine incorporates five different RSV antigens to stimulate a broad immune response against both RSV subtypes (A and B), thus mimicking the immune response observed following a natural response to an RSV infection.

We have rapidly advanced the clinical development of the vaccine and have generated highly promising Phase 2 results, confirming both broad and durable antibody and T cell responses against RSV, as well as mucosal immune responses that may be important for protection against RSV. The Phase 2 program in elderly included a revaccination of subjects after one year, following which the immune responses were rapidly and significantly increased, notably in subjects with the weakest immunity prior to the booster vaccination.

The Company has developed a Phase 3 program, originally planned to start in 2021. However, due to COVID-19 and the social distancing measures taken globally, the prevalence of other respiratory viruses, including RSV, has been lower and this may very likely continue into the 2021/22 season and as such could adversely affect the planned efficacy study. To maintain the momentum of the program despite the challenges faced by COVID-19, a Phase 2 human RSV challenge study has been planned for 2021, while also postponing the recruitment into the Phase 3 study until 2022. The human challenge study will generate the first efficacy data against RSV during 2021 and potentially further de-risk the Phase 3 efficacy trial.

RSV (respiratory syncytial virus) has been recognized as a significant cause of respiratory illness in all age groups. It is highly infectious and the most common cause of lower respiratory tract infection in infants and children worldwide, resulting in a high number of hospitalizations. RSV infections are also a serious health concern in the elderly and in adults with cardiopulmonary disease.

According to estimates from WHO, RSV infects more than 64 million people globally each year and causes a similar number of deaths as influenza, yet unlike influenza, there is no vaccine to prevent RSV.

There are only two subtypes of RSV, A and B, which are typically present either simultaneously or alternately during yearly epidemics.