Long-awaited trials to test two potential vaccines against the Ebola virus will begin in West Africa within the next few weeks, U.S. health officials said Thursday.
Plans are underway to conduct large-scale, random double-blind controlled trials of two vaccine candidates in Liberia and Sierra Leone.
“A safe and effective Ebola vaccine will undoubtedly be a critically important tool to help prevent Ebola virus infections in future outbreaks,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in a call with reporters Thursday. “And depending on the trajectory of the current epidemic, it could contribute significantly to its current containment.”
The National Institute of Allergy and Infectious Diseases will conduct clinical trials in Liberia of the vaccine candidate the agency co-developed with pharmaceutical giant GlaxoSmithKline. That potential vaccine uses a cold virus found in chimpanzees to deliver genetic material from the two Ebola strains responsible for the current Ebola outbreak. The second candidate that will be tested, known as rVSV-EBOV, was co-developed by drugmakers NewLink Genetics Corp. and Merck & Co., and is derived from strains of the vesicular stomatitis virus, a common animal virus, to carry Ebola protein.
In December, HHS awarded NewLink and Merck a $30 million contract to develop and manufacture its experimental vaccine.
Trials will involve those Fauci said are on the frontline of the Ebola outbreak, including healthcare workers and members of burial teams or households of those infected. Up to 27,000 people are expected to participate in the trial, which will take up to a year to complete, Fauci said.
As of Jan. 18, the number of Ebola cases since the start of epidemic has reached more than 21,000, according to the World Health Organization. More than 8,600 people have died. But the rate of new cases in Guinea, Liberia and Sierra Leone has been trending downward, with each country now having sufficient capacity to treat and isolate patients.
A second, smaller clinical trial of one of the vaccine candidates is expected to take place in Sierra Leone. It will be conducted by the Centers for Disease Control and Prevention and will target up to 6,000 participants. According to Dr. Anne Schuchat, director of CDC's National Center for Immunization and Respiratory Diseases, it is still unknown at this point which vaccine candidate will be used in Sierra Leone.
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