LONDON - Clinical trials of three potential Ebola treatments will begin in December in Guinea and Liberia at medical centres run by Medecins Sans Frontieres, the medical charity said on Thursday.

The separate trials, involving up to several hundred patients, are designed to test the drugs brincidofovir, from the US firm Chimerix, and favipiravir, from Japan's Fujifilm, and to see how well blood plasma taken from Ebola survivors may work in curing those still infected.

Initial results could be available in February 2015, MSF said in a statement.

The studies will not use placebo groups and will involve only Ebola patients who give informed consent. Researchers will monitor the patients and collect data on survival rates and other effects. The trials can be stopped early if a treatment begins to show clear benefits or harm.

Researchers said it may also be possible in coming months to add new experimental drugs to the trials if they become ready for testing.

Annick Antierens, a doctor who coordinates MSF's investigational partnerships, said the cooperation involved in conducting the trials was unprecedented and "represents hope for patients to finally get a real treatment".

The West Africa Ebola epidemic has infected more than 13,000 people, the vast majority in Guinea, Sierra Leone and Liberia, and killed some 5,000 of them, according to World Health Organization data.

The three trials will be led by different teams: Britain's University of Oxford will lead one in Liberia, and the Dutch Antwerp Institute of Tropical Medicine and the French National Institute of Health and Medical Research will lead two others in Guinea.

MSF said the trials are designed to minimise disruption to patients and respect internationally-accepted ethical standards with the aim that "sound scientific data will be produced and shared for public good".

The charity urged drugmakers to scale up production now, to try to ensure no gap between the end of the trials and any large-scale introduction of the medicines if they are found to be safe and effective.

"We need to keep in mind that there is no guarantee that these therapies will be the miracle cure," Antierens said. "But we need to do all we can to try the products available today to increase the chances of finding an effective treatment."

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