Candidates from Oxford and Moderna are the first built specifically for Bundibugyo virus to be tested during an outbreak
By Bunmi Yekini
The World Health Organization said expert groups have recommended adding two new vaccine candidates to a clinical trial in the Democratic Republic of the Congo, where an outbreak of Bundibugyo virus disease is under way.
The two candidates are ChAdOx1, developed by the University of Oxford with the Serum Institute of India, and Moderna’s mRNA-1469. The WHO said it is the first time vaccines designed specifically against Bundibugyo virus will be evaluated in the middle of an outbreak.
WHO’s Technical Advisory Group on Candidate Vaccines Prioritization recommended both this week, based on available preclinical and early clinical evidence. The companies were told on Monday. The vaccines will enter the trial once national approvals are in place.
“The fact that these vaccines are ready to enter clinical trials is a testament to the power of science and partnership,” WHO Director-General Tedros Adhanom Ghebreyesus said.
“Vaccines alone will not end this outbreak, but they could become a powerful new tool for bringing it under control,” he said.
The trial, called Tumaini, is led by the DRC’s national biomedical research institute, the Institut National de Recherche Biomédicale, with the University of Antwerp. Partners include the WHO, Epicentre, Médecins Sans Frontières, the Institute of Tropical Medicine in Antwerp, Africa CDC, the Congolese health ministry and the Institut National de Santé Publique. The Coalition for Epidemic Preparedness Innovations funded the rapid development of the candidates.
Tumaini tests several vaccines in one trial using ring vaccination, in which contacts of confirmed patients are enrolled. The method was pioneered during the West Africa Ebola outbreak a decade ago, when a trial in Guinea showed that the Ervebo vaccine worked against Zaire ebolavirus. Ervebo is also being assessed in Tumaini for efficacy against Bundibugyo virus.
Four vaccination rings are in place, with more being set up. They include contacts of people who fell ill or died from Ebola.
Work on treatments is also moving. The WHO-sponsored PARTNERS trial, launched in July, is testing whether the monoclonal antibody MBP134, the antiviral remdesivir, or both together improve survival in confirmed patients. Maftivimab will soon be added. A separate study of obeldevisir as post-exposure prophylaxis is under way.
WHO said initial findings from the treatment trials are expected in the coming months, and vaccine trial results in early 2027.