Ebola virus
Ebola virus
Credit: Festa. This image comes from Shutterstock

Oxford to lead Ebola vaccine trial

An unprecedented international consortium, including Oxford, has been assembled to accelerate trials of a candidate Ebola vaccine

Oxford University’s Jenner Institute is to start clinical safety  tests of a candidate Ebola vaccine, aimed at preventing the disease that has killed more than 1,200 people in the current outbreak in West Africa.

The candidate vaccine will be given to healthy volunteers in the UK, The Gambia and Mali from as early as September, as part of a series of safety trials.

The human trials of this vaccine, being co-developed by the US National Institutes of Health (NIH) and GlaxoSmithKline (GSK), are to be accelerated with international consortium funding in response to the Ebola epidemic. The World Health Organisation (WHO) has declared the outbreak a public health emergency of international concern.

The Jenner Institute team, led by Professor Adrian Hill has been funded with a £2.8 million grant from the Wellcome Trust, the Medical Research Council (MRC) and the UK Department for International Development (DFID). The money will allow the team to start safety tests of the vaccine alongside similar trials in the US run by the National Institute of Allergy and Infectious Diseases (NIAID, a part of the NIH).

The phase 1 trials will begin as soon as they receive ethical and regulatory approvals, which will be considered on an expedited basis. If approvals are granted, the UK research teams could start vaccinating volunteers from mid-September.

The consortium’s funding will also enable GSK to begin manufacturing up to approximately 10,000 additional doses of the vaccine at the same time as the initial clinical trials. If the trials are successful, stocks could be made available immediately by GSK to the WHO to create an emergency immunisation programme for high risk communities.

The candidate vaccine is against the Zaire species of Ebola, which is the one circulating in West Africa. The vaccine uses a single benign Ebola virus protein to generate an immune response. It does not contain infectious Ebola virus  material and therefore cannot cause a person who is vaccinated to become infected with Ebola.

Pre-clinical research by the NIH and Okairos, a biotechnology company acquired last year by GSK, indicated that it provides promising protection in non-human primates exposed to Ebola, without significant adverse effects.

The safety trials, involving small groups of healthy volunteers, are now required to ensure that the vaccine does not cause unforeseen side effects, and that it generates a good immune response to Ebola in humans. The trials are necessary before the vaccine can be rolled out to larger at-risk populations, even on an experimental basis.

Oxford’s Jenner Institute has extensive experience of clinical trials of similar vaccines, which they have evaluated clinically for six other diseases in Europe and Africa. To accelerate the Ebola trials, the NIH generously agreed to provide the NIAID/GSK Ebola vaccine for the Oxford studies, which will run in parallel to those in the US.

If the first volunteers vaccinated in the Oxford study show a good response with no adverse reactions, it will be extended to volunteers at the MRC Unit in The Gambia. A second West African arm of the study, led by Professor Myron M. Levine of the Center for Vaccine Development at the University of Maryland School of Medicine, and Professor Samba Sow of the University of Maryland Center for Vaccine Development in Mali, will then begin in Bamako, Mali.

The Oxford study will involve 60 volunteers, while those in The Gambia and Mali will each involve 40. Each set of volunteers will be split into groups of 20 that will receive different doses of the vaccine so researchers can evaluate the best dose to use in terms of both safety and activity.  The trial will be based at the Oxford Vaccine  Centre at the Churchill Hospital and interested potential participants are invited to contact the centre by email: [email protected].

NIAID are testing this same vaccine in the US, in addition to a related vaccine that is designed to protect against two Ebola species (Ebola Zaire and Ebola Sudan).

This collaborative multi-trial approach will help ensure the fastest possible progress to determining the best candidate vaccine approach and delivery. The addition of West African arms will also ensure that the studies take account of differences between European and West African populations that might affect safety or immune response.

It is hoped that the phase 1 trials might be finished by the end of 2014, after which deployment of the vaccine could be fast-tracked should it prove to be safe and immunogenic.

Professor Hill, Director of the Jenner Institute, said: “The tragic events unfolding in Africa demand an urgent response. In recent years, similar investigational vaccines have safely immunised infants and adults against a range of diseases including malaria, HIV and Hepatitis C. We, and all our partners on this project, are optimistic that this candidate vaccine may prove useful against Ebola.”

Dr Jeremy Farrar, Director of the Wellcome Trust, said: “This epidemic has shown how difficult it can be to control Ebola. How useful drugs and vaccines might be in complementing existing public health interventions can only be assessed in epidemics. The initial safety work we're announcing today with our international partners will hopefully make that possible during this crisis and for inevitable future epidemics.”

The UK’s International Development Secretary, Justine Greening said: “We are co-funding these important clinical trials to find a safe vaccine for Ebola as well as providing critical care on the ground. Britain is a world leader in medical research and mobilising our unique strengths to find a vaccine could be pivotal to containing Ebola and preventing future outbreaks.”