The first human trials of a vaccine against the deadly Ebola virus will start next week in the U.S., officials announced Thursday, just as the World Health Organization predicted as many as 20,000 people could be infected in West Africa before the epidemic is brought under control.
The National Institutes of Health will sponsor the first trial of the vaccine, one of several being developed against Ebola. It's fast-tracked the testing because of the outbreak of Ebola that is ravaging three West African countries.
"The early stage trial will begin initial human testing of a vaccine co-developed by NIAID and GlaxoSmithKline (GSK) and will evaluate the experimental vaccine's safety and ability to generate an immune system response in healthy adults," the NIH said in a statement. "Testing will take place at the NIH Clinical Center in Bethesda, Maryland."
Ebola has killed more than 1,500 people out of more than 3,000 infected in Liberia, West Africa and Guinea in the ongoing outbreak, by far the worst outbreak of Ebola ever seen. And the WHO says those numbers almost certainly understate the true numbers of those infected and killed. WHO predicted on Thursday that as many as 20,000 could become infected.
"In parallel, NIH has partnered with a British-based international consortium that includes the Wellcome Trust and Britain's Medical Research Council and Department for International Development to test the NIAID/GSK vaccine candidate among healthy volunteers in the United Kingdom and in the West African countries of Gambia (after approval from the relevant authorities) and Mali," NIH said.
"Additionally, the U.S. Centers for Disease Control and Prevention has initiated discussions with Ministry of Health officials in Nigeria about the prospects for conducting a Phase 1 safety study of the vaccine among healthy adults in that country."
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The National Institute of Allergy and Infectious Diseases, part of the NIH, has been working on an Ebola vaccine for years. The idea was to develop it to defend people in case Ebola or a related virus, Marburg, was ever used in a biological attack. Previous outbreaks of the virus were always too small and too easily controlled to justify developing a vaccine quickly.
NIAID was working with a small Swiss-Italian biotech company called Okairos to develop the vaccine. It's been shown to protect monkeys against Ebola.
Glaxo bought the company last year.
The next step is to test the vaccine in people, both to see if it's safe and to see if it stimulates the immune system in a way that would be predicted to protect people from infection.
The vaccine is made using a virus called an adenovirus that infects chimpanzees but not people. The virus is genetically engineered with a single piece of Ebola virus, a protein that the immune system can recognize, but which doesn't make people sick.
Several other companies are working to develop Ebola vaccines, including Crucell, a small biotech called Profectus Biosciences, Iowa-based NewLink Genetics and Immunovaccine Inc., based in Nova Scotia, Canada.
Two American medical missionaries, Dr. Kent Brantly and Nancy Writebol, were treated with an experimental therapy made by California-based Mapp Biopharmaceutical. Three Liberian doctors also received the drug. One died and the other two have recovered.
WHO published what it called a road map on Thursday for fighting the outbreak.
"Clearly, a massively scaled and coordinated international response is needed to support affected and at-risk countries in intensifying response activities and strengthening national capacities," it says.
"Response activities must be adapted in areas of very intense transmission and particular attention must be given to stopping transmission in capital cities and major ports, thereby facilitating the larger response and relief effort."
This outbreak is different from other outbreaks across Africa over the past 40 years, it says.
"This Roadmap assumes that in many areas of intense transmission the actual number of cases may be 2-4 fold higher than that currently reported," it says.
None of the provisions call for vaccination -- it's far to soon for that. Instead, the plan calls for better tracking down and diagnosis of cases, a fast-track training program to get more health workers on the job, safer burials and better control of travelers.
"Today we know the best way to prevent the spread of Ebola infection is through public health measures, including good infection control practices, isolation, contact tracing, quarantine, and provision of personal protective equipment," NIAID director Dr. Tony Fauci said in a statement. "However, a vaccine will ultimately be an important tool in the prevention effort. The launch of Phase 1 Ebola vaccine studies is the first step in a long process."
—By Maggie Fox, NBC News