FAQs about the context of this clinical trial

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Professor Claire-Anne SiegristProfessor
Claire-Anne Siegrist
Head of Vaccinology Center

1. Why did WHO ask the University Hospitals of Geneva to perform this clinical trial?

The proximity of the two institutions makes operations and contacts easier: WHO has asked the University Hospitals of Geneva (HUG) to store the VSV vaccine doses donated by the Public Health Agency of Canada, which will be used for all the phase I clinical trials. In addition, the HUG have internationally recognized scientific and medial expertise in clinical trials, vaccinology and virology. That is why they were selected to be among the four medical centres which will conduct the first trials of VSV-Ebola vaccine on humans.

Dr Marie-Paule Kieny, Assistant Director-General of WHO Health Systems and Innovation: "WHO is working with the University Hospitals of Geneva and Lausanne not only because of their proximity, but also because they have a worldwide reputation in clinical research."

2. Why not test this vaccine in areas affected by the epidemic? 

Phase I clinical trials aim primarily at determining vaccine safety as well as the dose required to trigger an immune response. These are preliminary tests for which it would be challenging to recruit volunteers who are directly exposed to the Ebola virus. Also, these people live in countries where it would not be easy to collect accurate data on vaccine safety.

Dr Marie-Paule Kieny, Assistant Director-General of WHO Health Systems and Innovation:
"Such trials are impossible to implement in the countries of West Africa affected by the Ebola virus, because their health systems are currently very much disturbed by the epidemic."

3. Will the future vaccines be given for free or will they be sold? 

WHO and GAVI (Global Alliance for Vaccines and Immunization) could distribute them for no charge, conditional on the availability of external funding (e.g. from the Wellcome Trust, the Bill & Melinda Gates Foundation, the Aga Khan Foundation or the World Bank). It is also likely that armies in different countries will secure a certain number of vaccine doses to counter any potential bioterrorist threat.

Dr Marie-Paule Kieny, Assistant Director-General of WHO Health Systems and Innovation:
"Vaccine producers will of course be financially compensated. Discussions are underway to set up a partnership which is likely to include GAVI – the Global Alliance for Vaccines and Immunization – and donor countries.”

4. If WHO decides on a large scale vaccination campaign, how will priorities be set? 

The vaccine will primarily be used to protect frontline medical workers who are in contact with people affected by Ebola virus disease, and staff in charge of cleaning infected premises and the bodies of people who have died of the disease. In the areas where the outbreak is out of control, massive vaccination of the population must be envisaged.

Dr Marie-Paule Kieny, Assistant Director-General of WHO Health Systems and Innovation:
"If the vaccine candidates prove effective, priorities for vaccination will be set by representatives of the three countries most affected by Ebola virus disease and by experts who are modeling the spread of the epidemic. Priority will be given to those most exposed to the virus: medical staff, and those in charge of cleaning medical premises and burying the victims."

Dr Vasee Moorthy, vaccine expert at WHO:
"It is difficult to predict when vaccines will be available. If the clinical trials are successful, we are told that a few thousand doses of vaccine will be available in the first months of 2015. If we further expand the number of laboratories able to produce vaccines, a high number of doses should be available by the end of 2015."

5. Why was this vaccine not been made available earlier to WHO? 

Between its discovery in 1976 and 2013, the Ebola virus caused between 10 and 100 deaths per year. Before the current outbreak, Ebola was therefore considered an "orphan disease" for which it was difficult to justify the launch of clinical trials costing tens to hundreds of millions of dollars. Experts also thought that the Ebola virus would always be kept in check through infection prevention control. The magnitude of the current epidemic has altered these views.

Dr Marie-Paule Kieny, Assistant Director-General of WHO Health Systems and Innovation:
"The vaccines were made available to WHO in August 2014. I would like to thank the University Hospitals of Geneva for having been so prompt in setting up the clinical trial to test this vaccine on humans for the first time."

6. Who is funding the clinical trial at the University Hospitals of Geneva? 

Costs related to the Phase I clinical trials at the University Hospitals of Geneva (115 volunteers), in Hamburg (40), Kenya (40) and Gabon (60) will be supported by the Wellcome Trust (UK), a charitable foundation supporting advances in global health.

7. Who funded the production of vaccines to be used at the University Hospitals of Geneva? 

The Canadian government. In August 2014, it declared that it would donate 800 doses of its experimental vaccine to WHO, as a contribution to the struggle against the epidemic.

8. What other vaccines are being considered by WHO ?

Only 2 vaccines are sufficiently advanced to be tested on humans now. One is the VSV-ZEBOV vaccine to be tested at the HUG, in Hamburg, Kenya and Gabon (and by the US Army).
The other is the chimpanzee adenovirus vaccine-chAd3. It will be tested at the CHUV (Centre Hospitalier Universitaire Vaudois) in Lausanne, in Mali, in Gambia and the USA. The first tests in humans started in September 2014 in the United States and the United Kingdom.

For updates, please visit the website of the CHUV

Dr Marie-Paule Kieny, Assistant Director-General of WHO Health Systems and Innovation:
"There are currently two vaccine candidates which may counter the Ebola virus; one based on a chimpanzee adenovirus and the other on the vesicular stomatitis virus. We are at an early stage of the evaluation. The first objective is to investigate how safe they are, what side effects they cause, and how good they are at generating an immune response."

Dr Vasee Moorthy, vaccine expert at WHO:
"There are several vaccines at pre-clinical research stages. The two vaccines whose clinical trials are supported by WHO offer important guarantees: they are produced using high quality laboratory processes and have been successfully tested on the best animal models – macaque monkeys. All monkeys vaccinated with these vaccines were protected against Ebola virus."


9. How can these vaccines contribute to stopping the current epidemic?

Dr Vasee Moorthy, vaccine expert at WHO: "Currently, those involved in the struggle against the epidemic should not rely only on the vaccines. Controlling the spread of the infection, tracing the contacts of infected persons and applying standard measures to control the epidemic are top priorities. We have high hopes for these vaccines, but they have yet to show their usefulness in protecting humans. Even if everything works according to plan, we do not expect to have sufficient amounts of vaccine before the end of 2015."

10. When and where will the other phase I clinical trials on the VSV vaccine take place?

Vaccination of volunteers by the US Army started in mid-October 2014. In Gabon, Kenya and Germany, clinical trials started in November or December 2014.


Dernière mise à jour : 29/01/2019