The first batch of an experimental Ebola vaccine has been dispatched to West Africa where it will be used in large-scale trials in coming weeks.
Healthcare workers helping to care for Ebola patients will be among the first to get the vaccine when trials start. Researchers hope to eventually enroll up to 30,000 people in the trial.
The vaccine, co-developed by the National Institutes of Health in the United States and Okairos, a biotechnology firm acquired by UK drugmaker GlaxoSmithKline (GSK) in 2013, is now being tested in safety trials in Britain, the US, Switzerland and Mali.
The vaccine uses a type of chimpanzee cold virus to deliver safe genetic material from the Zaire strain of Ebola, the strain responsible for the unprecedented West African epidemic.
Data show the vaccine is safe in people, including in a West African population and in a range of dose levels, GSK said.
Few cases left in Liberia
News of the first shipment of the vaccine coincided on Friday with the Liberian deputy health minister's announcement that the country only has five remaining confirmed cases of the disease.
"We have five confirmed Ebola cases in Liberia as of today," said Tolbert Nyenswah, who heads the country's Ebola taskforce.
"It means that we are going down to zero, if everything goes well, if other people don't get sick in other places."
Three of the remaining cases were in the capital Monrovia and the other two in Bomi and Grand Cape Mount Counties, he added.
It means that we are going down to zero, if everything goes well.
Nyenswah said last week that Liberia could be free of the virus by the end of next month.
In further positive news, Sierra Leone lifted quarantine measures imposed at the height of the Ebola epidemic on Friday.
The country of six million had restricted travel for around half its population, sealing off six of its 14 districts and numerous tribal chiefdoms in response to the outbreak which has killed more than 3,000 Sierra Leoneans.
"Restrictions on movement will be eased to support economic activity. As such, there will no longer be any district or chiefdom level restrictions on movement," President Ernest Bai Koroma said in an address to the nation.
The World Health Organisation said on Thursday the Ebola outbreak in West Africa, the worst in history, appears to be waning but cautioned against complacency.
The epidemic has seen 21,724 cases reported in nine countries since it started in Guinea a year ago. Some 8,641 people have died.