Tens of thousands of doses of experimental Ebola vaccines could be available for “real-world” testing in West Africa as soon as January as long as they are deemed safe, a top World Health Organization official said Tuesday.

Dr. Marie Paule Kieny, an assistant director general for WHO, said clinical trials that are either underway or planned in Europe, Africa and the U.S. are expected to produce preliminary safety data on two vaccines by December.

If the vaccines are declared safe, she said they will be used in trials in West Africa beginning in January to test their effectiveness among tens of thousands – but not millions – of people.

“I’m not suggesting at this moment that there would be mass vaccination campaigns at population levels starting in 2015,” she said, adding that none of the volunteers who take part in the trials could accidentally contract Ebola from the testing.

The Ebola outbreak in West Africa has already killed over 4,500 people, mostly in Liberia, Guinea and Sierra Leone, since it emerged 10 months ago. Experts have said the world could face 10,000 new cases of Ebola a week in two months if authorities don’t take stronger steps to fight the deadly virus.

Safety isn’t the only question before larger studies of the vaccines begin – the shots must also trigger an adequate immune-system response in the first volunteers tested.

One of the two vaccines that Kieny mentioned was developed by the U.S. National Institutes of Health and GlaxoSmithKline (NYSE: GSK) from a modified chimpanzee cold virus and an Ebola protein. It is in clinical trials now in the U.K. and in Mali and will be used in trials in Lausanne, Switzerland, by the start of February.

GSK Gearing Up

In its latest update about the vaccine, GSK noted the progress being made and possible next steps.

“This investigational vaccine has shown promising results in pre-clinical (non-human) studies. Clinical development of the vaccine candidate is progressing at an unprecedented rate, with first phase 1 safety trials with the vaccine candidate underway in the USA, UK and Mali, and further trials due to start in the coming weeks. These will study the safety of the vaccine and if it generates a good immune response to Ebola in humans. Initial data from the phase 1 trials are expected by the end of the year,” GSK explains in a website devoted to Ebola.

“The UK-led trials are being supported by funding from an international consortium involving the Wellcome Trust, the Medical Research Council and the UK Government.

“In parallel, funding from the consortium is enabling GSK to begin manufacturing around 10,000 additional doses of the vaccine. This means that, if the phase 1 trials are successful, we can begin the next phases of the clinical trial programme in early 2015 which will involve the vaccination of thousands of frontline healthcare workers in the three affected countries – Sierra Leone, Guinea and Liberia. If the vaccine candidate is able to protect these healthcare workers as we hope it will, it could significantly contribute to efforts to bring this epidemic under control.”

GSK operates its North American headquarters in Research Triangle Park, N.C.

Two other Triangle firms, Chimerix and BioCryst, also have Ebola vaccines under development.

GSK says the vaccine is being manufactured at a plant in Rome, which Glaxo acquired last year along with the Italian company that developed the Ebola vaccine, Okairos AG.

“We have other vaccine facilities around the world and we are seeing what we can do to ramp up production to commercial scale,” said Mary Anne Rhyne, Glaxo’s U.S. director of external communications.

A Second Vaccine

The second front-runner, developed by the Public Health Agency of Canada and known as VSV-EBOV, has been sent to the U.S. Walter Reed Army Institute of Research in Maryland for testing on healthy volunteers, with preliminary results about its safety expected by December. The next stage would be to test it more broadly, including among those directly handling Ebola cases in West Africa.

Canada has donated 800 vials of the experimental vaccine to WHO but the shipment was delayed by a Lufthansa pilots’ strike. Those are now expected to arrive in Switzerland on Wednesday for testing coordinated by the U.N. health agency among volunteers at the University Hospital of Geneva, and volunteers in Hamburg, Germany, and in Gabon and Kenya, Kieny said.

“These data are absolutely crucial to allow decision-making on what dose level should go in the efficacy testing in Africa,” Kieny said. “We expect, we hope, to have a go-ahead by the end of the month.”

That would allow the vaccine to be shipped for use in Africa immediately afterward.

Kieny said decisions about “which strategy to use and how and where and who” regarding the vaccines will be made in the next few weeks. Then vaccines will be given to health workers and select segments of the general population “early in 2015, in January.”