Moncef Slaoui

Ebola: our fast track response

The Ebola outbreak spread across West Africa at unprecedented scale and speed. GSK responded to the crisis by contributing humanitarian support and accelerating the development of an investigational Ebola vaccine. Dr Moncef Slaoui explains how GSK took action to fast track the development of a candidate vaccine for clinical trials.

We are committed to fast tracking the development and manufacture of our investigational Ebola vaccine, to try and help tackle the current Ebola outbreak and prevent any in the future.

The candidate Ebola vaccine uses components from a type of chimpanzee cold virus combined with a single protein taken from the Zaire strain of Ebola – the type responsible for West Africa’s current epidemic. First results of early stage studies in healthy volunteers in the UK, US, Switzerland and Mali are encouraging and suggest that the vaccine has an acceptable tolerability profile, and can generate an immune response against Ebola. We don’t know yet whether this investigational vaccine will be effective though.

A larger scale phase III trial began this January in Liberia that aims to establish whether the candidate vaccine can actually protect people against Ebola. We shipped the first doses of our candidate Ebola vaccine to West Africa in January to enable this study to start.

The large phase II/III clinical trial (PREVAIL) involving the candidate vaccine and led by the US National Institutes of Health (NIH) began in Liberia. The trial compares the GSK’s candidate vaccine (and the candidate vaccine from Merck) to a control vaccine, to assess whether the immune response seen in phase I trials translates into meaningful protection against Ebola.

The WHO (World Health Organization) has also announced that GSK’s vaccine candidate will be included in the WHOs phase 3 efficacy trial in Guinea.

We have only been able to fast track development of the Ebola vaccine because of the extraordinary collaboration between many different organisations, including the U.S. National Institutes of Health, the WHO, the Wellcome Trust and the UK Government

We have dedicated significant resources trying to industrialise the process we use to manufacture the trial Ebola vaccine, so we can make it in large quantities. Some major challenges continue to face us in scaling up the production of this vaccine: just filling vials with trial Ebola vaccine under the sterile conditions required, for example, without derailing the production of other life-saving vaccines that are extremely important for public health.

If the vaccine proves successful, we’ll work closely with our partners to make sure it gets to the people who need it. I’m pleased that we are seeing groups like Gavi, [1] the Global Vaccine Alliance for Immunisation, make funds available for future Ebola vaccines.

It is likely that Ebola will return in the affected countries or others in the region because the virus is endemic and cannot be eradicated completely. What the global public health community is learning through the emergency response, though, is that together we can hope to be able to tackle Ebola.

While our experience will be invaluable in our response to any and all future Ebola outbreaks, the global community must design and implement more proactive preparedness approaches to further improve our capacity to prevent and/or quickly control unpredictable disease outbreaks such as Ebola, but also SARS, Pandemic Flu and many others…


[1] Gavi: Created in 2000, Gavi is an international organisation – the Global Vaccine Alliance Initiative. Gavi brings together the public and private sectors with the shared goal of creating equal access to new and underused vaccines, for children living in the world’s poorest countries.

infographic ebola

Ebola vaccine journey infographic

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