Liz Szabo

USA TODAY

Doctors Without Borders will begin clinical trials of three experimental Ebola therapies in West Africa in December, the aid group announced Wednesday.

The studies will test therapies already used in some Eblola patients in the USA and Europe: the antiviral drugs brincidofovir and favipiravir, as well as blood donations from Ebola survivors.

Brincidofovir, made by Chimerix of North Carolina, was given to cameraman Ashoka Mukpo, Liberian national Thomas Eric Duncan and physician Craig Spencer. Mukpo and Spencer survived. Duncan received the drug just a couple days before he died.

Favipiravir, an anti-flu drug made by Japan's Fujifilm Holding Corp., was given to a French nurse who worked with Doctors Without Borders.

And blood donations from Ebola survivors, which contain antibodies against the virus, have been used since the first Ebola outbreak in 1976.

More recently, American Ebola patient Kent Brantly, a physician, received a blood donation from a teenage survivor before he left Liberia for treatment at Atlanta's Emory University Hospital. He later donated blood to several other Ebola patients: Mukpo, physician Richard Sacra and nurses Nina Pham and Amber Vinson. Missionary Nancy Writebol, also treated at Emory, donated blood to Vinson and Spencer.

Brantly and Writebol also both received the experimental drug ZMapp. Supplies of that drug, which takes months to manufacture, are now exhausted.

None of those treatments has been proven to work. Although all eight American patients survived, scientists can't say for certain what allowed them to beat the odds, because each received several types of therapy, said Amesh Adalja, senior associate at the Center for Health Security at the University of Pittsburgh Medical Center. And the number of patients treated, even including the additional handful in Europe, was too small to allow researchers to draw any conclusions.

More than 13,000 peoiple have been infected with Ebola in Sierra Leone, Guinea and Liberia, and nearly 5,000 have died, according to the World Health Organization.

The trials will be an international effort involving the World Health Oganization, the University of Oxford, the Wellcome Trust, the International Severe Acute Respiratory and Emerging Infection Consortium, the French National Institute of Health and Medical Research, and the Antwerp Institute of Tropical Medicine in the Netherlands.

"This is an unprecedented international partnership that represents hope for patients to finally get a real treatment against a disease that today kills between 50% and 80% of those infected," Annick Antierens of Doctors Without Borders said in a written statement.

Initial results could be available in February 2015.

"Conducting clinical trials of investigational drugs in the midst of a humanitarian crisis is a new experience for all of us, but we are determined not to fail the people of West Africa," Peter Horby, chief investigator of the brincidofovir trial, said in a written statement.

Doctors Without Border has urged the drugs' developers to scale up production now, to be ready to provide them to large numbers of patients at an affordable price.

Peter Hotez, dean of the National School of Tropical Medicine in Houston, called the trials "very important and highly welcomed."

"Real-time research during public health emergencies is crucially important, whether for Ebola or pandemic influenza," Adalja said.

The WHO has said that it expects vaccine studies to begin in Africa by January.