Why is this study being done?
The current outbreak of Ebola virus disease in West Africa is estimated by the World Health Organization to have caused more than 10,000 deaths to date and is still ongoing. This outbreak is caused by a variant of the Ebola virus called the Zaire strain. There is no effective treatment or cure for Ebola and an effective vaccine would be an important step in controlling the spread of disease.
A vaccine is a medical product given to prevent infectious diseases by stimulating the human body to form a protective response against the infection. This protective response is called the immune response, and it is our body’s way of fighting diseases.
EBOVAC 2 (phase 2 clinical studies) has been selected by the Innovation Medicines Initiative Ebola+ programme to expedite the vaccine regimens development.
How do the EBOVAC2 trials differ from other ongoing trials?
The prime-boost vaccine regimen strategy requires two vaccinations with two different vaccines. The advantage of this strategy is the potentially better and more durable immunity. This is original in the Ebola context and different from other ongoing vaccination strategies with only one vaccination.
What is the purpose of the phase 2 studies?
The main objective of EBOVAC2 is to provide extensive and robust data on the safety and immunogenicity of the Ad26.ZEBOV and MVA-BN-Filo vaccine regimen. The immune response of different vaccine schedules for prevention of the Ebola virus infection will be compared. The same vaccines are used for all schedules, except that the timing of the boost (2nd) vaccination is different.
Who are the volunteers?
In Europe: healthy adults aged 18 to 65 years.
In Africa: volunteers include healthy adults and elderly aged up to 70, HIV positive adults an healthy children and adolescents aged 1 to 17 years.
Who is undertaking the trials?
The phase 2 studies in Europe and Africa are sponsored by Crucell Holland B.V., one of the Janssen Pharmaceutical Companies of Johnson & Johnson, and coordinated by Inserm.
What is known about these vaccines?
The experimental vaccines used in this study are called Ad26.ZEBOV and MVA-BN-Filo.
Ad26.ZEBOV is a vaccine regimen designed to provide active specific acquired immunity to the Ebola virus (formerly known as Zaire ebolavirus).
MVA-BN-Filo® is a vaccine preparation designed to provide active acquired immunity to the Sudan virus, the Ebola virus, the Marburg virus, and the Tai Forest virus (formerly known as Côte d’Ivoire ebolavirus).
Ad26.ZEBOV and MVA-BN®-Filo® have been studied in animals and are well tolerated so far. The vaccines are currently being tested in phase 1 studies in healthy volunteers in the US, the UK and Africa. Immunizing with these vaccines is expected to stimulate the body’s immune system and may provide protection against infection with the Ebola virus.
Neither Ad26.ZEBOV nor MVA-BN-Filo® are approved by agencies for use in any country. Therefore, they can only be used for research purposes such as in these clinical studies.
Could the vaccine infect trial participants with Ebola?
No, these vaccines will not cause Ebola infection. The genetic material contained in the investigational vaccine cannot cause someone to become infected with the Ebola virus. Trial participants that have received the investigational vaccines will develop antibodies against this genetic material, but this does not mean that they have been infected.
How long is the study?
Participants receiving the study vaccines will be involved in the study for about 1 year, while those receiving the placebo will be in the study for approximately 10 to 18 weeks.
Will participants have side effects from participating in the studies?
The well-being and safety of study participants is always our top priority.
The Phase 2 study protocols are being reviewed by appropriate regulatory authorities and ethics committees. These reviews are done to help ensure that the study would be scientifically, ethically, and clinically appropriate and that it would adhere to accepted standards for protecting human clinical research participants. However, some participants may experience side effects. A number of safety features are built into the study’s design, including daily and weekly reviews of patient data by clinical staff and the study protocol team.
See EBOVAC1 and EBOVAC3 website for more information.