Periodic Reporting for period 5 - EBOVAC3 (Bringing a prophylactic Ebola vaccine to licensure)
Reporting period: 2022-06-01 to 2023-07-31
Significant progress has been made in the development of this vaccine regimen, in large part due to the contributions made through the above-named IMI-funded projects. On the 1st July 2020, the European Commission granted marketing authorisation to the Janssen Ebola vaccine regime, Zabdeno® (Ad26.ZEBOV) and Mvabea® (MVA-BN-Filo). Data from the EBOVAC 1, 2 and 3 projects were used in the vaccine’s approval process. The authorisation was granted in one month, following a positive opinion adopted by the European Medicine Agency’s Committee for Medicinal Products for Human Use (CHMP) demonstrating the importance of this preventative tool to the Commission and its public health agenda. The Janssen Ebola vaccine regimen, Zabdeno® (Ad26.ZEBOV) and Mvabea® (MVA-BN-Filo), was also granted WHO Prequalification in April 2021. This will facilitate registration of the vaccine in African countries and allow broader access to communities at risk for EVD. The WHO and the government of Sierra Leone have recently begun administering the Janssen Ebola vaccine regimen as part of a WHO early access clinical program aimed at preventing further spread of Ebola in West Africa. In June 2021, the Strategic Advisory Group of Experts (SAGE) on Immunization for the World Health Organization (WHO) granted a recommendation in support of the use of Janssen two-dose Ebola vaccine regimen, Zabdeno® (Ad26.ZEBOV) and Mvabea® (MVA-BN-Filo), both during outbreaks for individuals at some risk of Ebola exposure and preventively, before outbreaks, for national and international first responders.
EBOVAC3 aims to further support the vaccine regimen licensure pathway, providing information on long-term safety and antibody persistence following vaccination and, on the safety, and immunogenicity of the vaccine regimen in infants and health care workers. The project is also preparing for future Ebola outbreaks through activities including mathematical modelling and social science research.
• EBL2005 (Safety and immunogenicity study of the two-dose heterologous vaccine in healthy infants in Guinea & Sierra Leone): the study is complete and results are available.
• EBL2007 (Open-label safety and immunogenicity study of the two-dose heterologous vaccine regimen in health care providers in the Democratic Republic of Congo): the study follow-up and laboratory analyses have been completed and data analysis is ongoing.
• EBL3005 (Long-term safety and immunogenicity study of the two-dose heterologous vaccine regimen in Sierra Leone): the study follow-up and laboratory analyses have been completed and data analysis is ongoing.
• EBL2012 (Open-label safety and immunogenicity study of the two-dose heterologous vaccine regimen in adults and children originally enrolled in the control arm of the EBOVAC-Salone study): the study follow-up has been completed and sample laboratory analyses are ongoing.
For all four trials, study documents including protocols and informed consent forms were developed and approved by the relevant ethics and regulatory authorities. Study sites in Guinea, Sierra Leone, and the Democratic Republic of Congo were identified and site preparations such as staff recruitment and training were carried out. All the first three trials (EBL2005, EBL2007 and EBL3005) started in 2019, reached target recruitment in the second year of the project and have completed participant follow-up. The EBL2012 study has also completed participants’ follow-up.
EBOVAC3’s outbreak preparedness activities were established in the first year of the project. Research protocols were developed for social science research in Guinea and Sierra Leone to examine community understanding, expectations and acceptance of various Ebola vaccine strategies. Data collection started in 2019 and is now complete. The deliverable D5.1 report is under preparation. A workshop was held in March 2022 in Conakry, Guinea, with ethics committees and regulators from Guinea and Sierra Leone to summarise their experiences during the EVD outbreak in 2014-2016. In DRC, a set of interviews were conducted in 2021 with members of ethics committees, health authorities, health professionals and political authorities to collect their experiences during several Ebola outbreaks in recent years.
The work of the EBOVAC family of projects is therefore as important as ever to the global fight against Ebola and supported the licensure in July 2020 of the two-dose Ebola vaccine regimen for prophylactic use in adults and children ≥1-year-old in the European Union. This also enabled WHO prequalification, which was granted in April 2021.
The data gathered from the clinical trials implemented by the EBOVAC3 project could contribute further to the licensure pathway of the two-dose vaccine regimen, providing additional data on the long-term safety and persistence of immune response associated with the vaccine, as well as the safety and immunogenicity of the vaccine in infants and healthcare workers specifically. This will inform the clinical use of the vaccine regimen and facilitate real-world vaccination efforts to combat or prevent future outbreaks of Ebola.
The preparedness activities will inform an understanding of how best to deploy the vaccine to fight Ebola in ways that are tailored to communities and meet the capacities of governments and regulatory authorities.
The economic and social costs of combatting an Ebola epidemic are significant for all affected countries and international responders, including countries in the European Union who provide humanitarian aid. One estimate of the total economic and social burden from the 2014-2016 West Africa Ebola outbreak was $53 billion. An effective vaccine offering long-lasting protection against Ebola could therefore have a significant impact in at-risk countries and also for Europeans.