A global group says it will pay pharmaceutical company Merck & Co. $5 million for a stockpile of an Ebola vaccine that showed success in a trial in Guinea last year following the 2014 outbreak of the deadly virus disease in Africa.

Gavi, a Geneva-based organization that works to help poor countries vaccinate their children, made the announcement Jan. 20 at the World Economic Forum in Switzerland.

The vaccine, being developed by the U.S. drug manufacturer and still in the investigative stage, would be held for use in emergencies or for further clinical trials, Gavi said in a statement.

It is the first time the organization has committed to purchasing a vaccine before it has been licensed.

Its $5 million to Merck is what is known as an "Advance Purchase Commitment," a guarantee that Gavi will buy the vaccine once approved.

"It says the company [Merck] is not going to be left holding the bag," for the costs of research and development, said Dr. Seth Berkley, Gavi CEO.

The agreement "will help Merck take the vaccine through licensure and WHO prequalification," the organization said in its statement.

Merck said it was committed to producing and stockpiling 300,000 doses and embarking on the approval process.

If the drug, known as VSV-EBOV, wins eventual approval, it would be among the world's first licensed Ebola vaccines.

The announcement comes as concerns continue about recent cases of Ebola showing up in West Africa, where the 2014 outbreak killed more than 11,000 people in Liberia, Guinea and Sierra Leone and infected 28,600.

There were also deaths from Ebola in Mali, Nigeria and the United States.

"The most recent Ebola-related death in Sierra Leone and the fact that we know the reservoirs of Ebola still exist underline why we must learn lessons from the devastating impact of the crisis and ensure we are better prepared for infectious disease outbreaks," Berkley said.

Doctors without Borders, which has been conducting the Guinea trial with the Merck vaccine, says it has extended that trial to Sierra Leone and plans to continue the use of the vaccine in an investigative mode if another outbreak should happen.

"The world is still worryingly underprepared for potential future health threats and a change of mindset is required to ensure we invest in research and development today to protect ourselves in years to come," Berkley added.