The ongoing outbreak centred on DR Congo is fuelled by the Bundibugyo variant of the virus.
There is no approved vaccine but the World Health Organization said experts have recommended adding two new candidate drugs to an ongoing clinical trial.
The vaccines, one developed by the University of Oxford and the Serum Institute of India, and another by the firm Moderna, will join the trial once they are approved by Congolese health authorities.
It will be the first time jabs specifically designed to protect against the Bundibugyo virus are tested during an outbreak.
Since the outbreak, Ebola cases have also been confirmed in Kenya, Nigeria and Uganda.
