GlaxoSmithKline has said the Ebola vaccine it is currently trying to fast-track through trials will come too late for the current epidemic.
The pharmaceuticals firm has been working on a vaccine for the virus, with trials already taking place in Africa, the US and the UK.
But the head of the company's Ebola vaccine research has said necessary data and manufacturing levels will not be ready until next year, or even the year after.
Dr Ripley Ballou told BBC Radio 4's File on Four: "To have a vaccine that people can use, you have to have the vaccine registered and it has to be manufactured on a scale that is consistent with the intended use.
"It is going to be well into next year if not the year beyond before we have that kind of level of manufacturing and the data that is necessary."
A GSK spokesman told The Independent the first phase of trials with the GSK/NIH vaccine were underway in the US, the UK and Mali, while further trials were due to start in the coming weeks.
See the Ebola outbreak mapped
See the Ebola outbreak mapped
1/7 25 March 2014
This outbreak of the Ebola virus first emerged in the Guéckédou region of Guinea, at a crossroads with both Liberia and Sierra Leone
2/7 31 March
On 31 March the WHO confirmed the outbreak was now international, spreading first into Liberia's northern-most Lofa region
3/7 27 May
The virus spread to Sierra Leone at the end of May - just as agencies were hoping the worst was over
4/7 27 July
In Sierra Leone the virus boomed, and then it spread to Nigeria when the Liberian diplomat Patrick Sawyer flew from Monrovia to Lagos
5/7 9 August
The Nigeria cases sparked fears around the world, and there have now been deaths in Spain and Saudi Arabia involving people who had travelled to West Africa. The numbers of cases continue to rise
6/7 17-20 September
In mid-September, Senegal confirmed its first case linked to the Ebola outbreak, a development the WHO described as a top priority emergency. Numbers of cases continued to grow exponentially in Guinea, Sierra Leone and Liberia, as experts warned they could number one million by January if not contained
7/7 8 October
Two cases of Ebola have now been reported in the US and Europe - the first times the virus has been contracted among health workers outside Africa
The spokesman said: "Early safety and immunogenicity data will be available later this year, with the trials expected to be finished by mid-2015.
"In parallel, GSK has begun manufacturing approximately 10,000 additional doses of the vaccine candidate so that if the phase one trials are successful, we can begin the next phases of the clinical trial programme as soon as possible.
"We hope to commence these trials early in 2015 which are likely to include high risk populations, such as frontline health workers in the three affected countries, including Sierra Leone, Guinea and Liberia.
"Beyond that, are working with other partners and stakeholders to try to accelerate the development of manufacturing at an industrial scale so that if the trials are successful, we will be in a position to significantly ramp up production to help combat this or future Ebola outbreaks."
David Cameron today insisted Britain was "leading the way" in providing assistance to West Africa as he urged other members of the international community to "look to their responsibilities" to help tackle the Ebola epidemic.
The Prime Minister backed a call by United Nations secretary-general Ban Ki-moon for other countries to deliver more in the way of funding and resources.
"This is the biggest health problem facing our world in a generation," Mr Cameron said as he arrived at the 50-plus Asia Europe Meeting in Milan, Italy.
"It is very likely to affect a number of the countries here today.
"Britain, in my view, has been leading the way. The action we are taking in Sierra Leone where we are committing well over £100 million, 750 troops, training 800 members of health staff, providing 700 beds - we are doing a huge amount.
"I think it is time for other countries to look at their responsibilities and their resources and act in a similar way to what Britain is doing in Sierra Leone, America is doing in Liberia, France is doing in Guinea.
"Other countries now need to step forward with resources and action because taking action at source in West Africa is the best way to protect all of us here in Europe."
His call came after Mr Ban said last night that a "huge and urgent global response" was needed to deal with the crisis and that countries which have "the capacity" should provide funding now.
"This is quite serious. We need an urgent global response and support," he said.
Additional reporting by Press Association