Project Summary:

The Ebola vaccine projects – EBOVAC1, EBOVAC2, EBOVAC3, EBODAC and EBOMAN – are a series of trials and associated projects, which aim to assess a novel prime-boost preventive vaccine regimen against Ebola Virus Disease (EVD). In a prime-boost vaccine regimen, individuals are first given a dose to prime the immune system, and then a boost dose, which is intended to enhance the immune response and increase the duration of the response. The vaccine has been developed by Janssen Vaccines and Prevention B.V. and the trials are funded by the Innovative Medicines Initiative (IMI, a partnership between the EU and the European pharmaceutical industry).

Between them the EBOVAC1 and EBOVAC2 projects will assess – through several clinical trials conducted in phases in Europe and Africa – the safety, tolerability and immunogenicity of the vaccine regimen in response to the urgent public health need raised by the Ebola epidemic.

The EBOVAC3 project aims to support an essential part of the remaining clinical and manufacturing activities required for the licensure of the two-dose vaccine regimen in the European Union and the United States.

Building on work carried out under the EBOVAC1 and EBOVAC2 projects, EBOVAC3 is running clinical trials to gather safety and immunogenicity data in infants in Sierra Leone and Guinea; as well as health care workers in an area unaffected by Ebola in the Democratic Republic of Congo. It is also following up participants who received the vaccine regimen in the EBOVAC-Salone trial in Sierra Leone to assess the safety and immunogenicity of the regimen in the longer term.

In addition to the clinical trials, EBOVAC3 aims to characterise outbreak preparedness in Sierra Leone, Guinea and the Democratic Republic of Congo through social science research, and mapping of the existing preparedness activities in each of the three countries.

The EBOVAC1 project in Sierra Leone also includes the PREVAC study. PREVAC is a large, randomized, placebo-controlled Phase II clinical trial to assess the safety and ability of three different Ebola vaccine strategies to stimulate an immune response that may protect against Ebola virus disease.

The PREVAC-UP project is built around the PREVAC consortium. Its two primary objectives are to determine (i) the long-term immunogenicity and safety and (ii) durability of humoral and cellular immune responses of Ebola vaccine regimes over 60 months. The project also aims to evaluate the effect of co-infections, such as malaria and helminths on the immune response to vaccination. An integrative statistical analysis of the immune response will be used to explore the mechanism of action of the vaccines and to identify early correlates of durable antibody induction. The project also builds on the extensive community mobilisation efforts previously generated through PREVAC to provide a trans-national platform for social and health science research and training. Finally, this project will expand and sustain capacity building and training of scientists in the four participating African countries.

For both trials extensive social science research has been conducted with adult and adolescent participants and people from the local communities exploring understandings and experiences of the trials and the vaccine in a post-Ebola context.