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GSK statement on Oxford University phase I trial results of an Ebola candidate vaccine

Results from a phase I trial published today by Oxford University in the New England Journal of Medicine (NEJM) show that a GSK/NIH Ebola candidate vaccine demonstrated an acceptable safety profile

Results from a phase I trial published today by Oxford University in the New England Journal of Medicine (NEJM) show that a GSK/NIH Ebola candidate vaccine demonstrated an acceptable safety profile and produced an immunological response in 59 healthy adult volunteers. Based on these results and others, GSK has already shipped the first doses of the vaccine candidate to Liberia in preparation for the start of a Phase III clinical trial sponsored by the NIH in the coming weeks.

The study published today assessed three different doses of a monovalent version of the GSK/NIH candidate vaccine which specifically targets the Zaire strain of Ebola that is currently causing disease in west Africa. The candidate vaccine was well tolerated at all three doses.

The primary goal of the trial was to assess safety, but immune responses were also measured and the candidate vaccine was shown to generate an immune response against Ebola.

Commenting on the results, Dr Moncef Slaoui, Chairman of Global Vaccines at GSK said: “We have been encouraged by the positive phase I results we have seen so far from this trial and others. It is on the basis of the totality of all the phase I results that we examined that we took the decision to ship the first doses of GSKs vaccine candidate to Liberia last week.

While these developments are heartening, it is important to remember that this vaccine is still in development and any potential future use in mass vaccination campaigns will depend on whether WHO, regulators and other stakeholders are satisfied that the vaccine candidate provides protection against Ebola without causing significant side effects and how quickly large quantities of vaccine can be made.”

The candidate vaccine used in the trial conducted by Oxford University was co-developed by the NIH’s National Institute of Allergy and Infectious Diseases (NIAID) and Okairos, a biotechnology company acquired by GSK in 2013. It uses a type of chimpanzee cold virus, known as chimpanzee adenovirus type 3 (ChAd3), as a carrier to deliver benign genetic material from the Zaire strain of the Ebola virus, which is responsible for the current Ebola outbreak in west Africa.

Next steps

  • Next phases of the clinical trial programme are expected to begin shortly involving the vaccination of thousands of frontline healthcare workers in Liberia in an NIH sponsored trial. GSK has already shipped 300 vials of our vaccine candidate to Liberia.
  • GSK is exploring how we can also provide vaccine for other phase3 trials being considered in Sierra Leone and Guinea
  • GSK continues to work with the WHO, regulatory agencies and other stakeholders to determine potential solutions to accelerate the development of the candidate Ebola vaccine with the goal of trying to limit the further spread of the epidemic.
  • Its potential future use in mass vaccination campaigns will depend on whether WHO, regulators and other stakeholders are satisfied that the vaccine candidate provides protection against Ebola without causing significant side effects and how quickly large quantities of vaccine can be made.
  • We are actively exploring with relevant organisations and partners all opportunities to accelerate the development of manufacturing at an industrial scale.
  • We are also looking at whether use of a booster vaccine may help provide longer-lasting protection.