Two new Ebola vaccines are expected to join clinical trials in the DR Congo

Two new Ebola vaccine candidates designed to protect against the Bundibugyo strain of Ebola are set to join an ongoing clinical trial in the Democratic Republic of the Congo (DRC)

The World Health Organization (WHO) has recommended that both vaccines undergo further clinical testing as research into potential ways to prevent and treat the disease continues.

Two new vaccine candidates are recommended

The Ebola vaccine ChAdOx1, developed by the University of Oxford in partnership with the Serum Institute of India, and Moderna’s mRNA-1469.

Both Ebola vaccine candidates have been selected following a review of available early clinical and preclinical evidence by an independent WHO advisory group.

If they receive national approval, the vaccines will be added to the Tumaini clinical trial. This will be the first time vaccines specifically developed to protect against the Bundibugyo virus are tested during an active outbreak.

The DRC’s Institut National de Recherche Biomédicale is leading the trial, working alongside international research organisations and health partners.

How the Tumaini trial works

The Tumaini trial uses a ring-vaccination approach, which involves offering vaccines to people who have been in contact with confirmed Ebola patients.

Four vaccination rings have already been established, with several more being prepared. The study is designed to assess multiple vaccine candidates within one trial.

The existing vaccine, Ervebo, is also being evaluated to determine its effectiveness against the Bundibugyo virus. It was previously shown to be effective against the Zaire strain of Ebola during an outbreak in West Africa.

Treatment research also progressing

Alongside vaccine development, researchers are investigating potential treatments for people infected with the virus.

The WHO-supported PARTNERS trial is assessing whether the monoclonal antibody MBP134, the antiviral drug remdesivir, or a combination of both can improve survival rates.

Another treatment, maftivimab, is expected to join the study, while a separate investigation is examining obeldevisir as a possible post-exposure prevention option.

When could results be available?

Initial findings from the treatment studies are expected in the coming months, while results from the vaccine trial are anticipated in early 2027.

The research could provide important evidence to help improve the response to future Ebola outbreaks. However, vaccination and treatment will need to work alongside wider public health measures to bring the current outbreak under control.