WHO Begins Ebola Vaccine Trial in DR Congo

The first clinical trial of an Ebola vaccine during the outbreak in the Democratic Republic of the Congo (DR Congo) began on Friday, the head of the World Health Organisation, Tedros Adhanom Ghebreyesus, has announced.

The country’s worst-ever Ebola outbreak has recorded more than 9,700 cases and over 4,600 deaths.

One major challenge facing the response is the lack of approved vaccines or treatments specifically for the Bundibugyo virus, the strain responsible for the current outbreak.

The trial will assess whether an existing Ebola vaccine, Ervebo, which is approved against the more common Zaire strain, offers any protection against the Bundibugyo strain.

In a post on X, Tedros said the first participants received the vaccine in Bunia, DR Congo, under a clinical trial named Tumaini, which means “hope” in Swahili.

“Science gives us hope. Today, in Bunia, DRC, the first participants were vaccinated in a new Ebola vaccine trial called Tumaini, which means ‘hope’ in Swahili,” he said.

“This trial will help us understand whether any of the vaccine candidates designed for Bundibugyo virus work.

“In the meantime, the existing Everbo vaccine (licensed for use in preventing other Ebola virus disease) will be tested.

“WHO is supporting this DRC-led effort to find answers and save lives.”

The Tumaini trial uses a single clinical trial framework to assess the safety and effectiveness of multiple vaccine candidates. In addition to Ervebo, the trial is expected to incorporate two experimental vaccines specifically designed to target the Bundibugyo virus. Both candidates are undergoing earlier-stage clinical trials.

One is a ChAdOx1 adenoviral vector vaccine being developed by the University of Oxford, while the other is an mRNA-based candidate developed by US pharmaceutical group Moderna.

The trial is expected to provide evidence on whether the vaccines can help protect people against the Bundibugyo strain, for which no vaccine or treatment has been approved.

The WHO is supporting the DR Congo-led initiative as health authorities continue efforts to contain the outbreak and reduce further deaths.