The Democratic Republic of Congo is battling its worst outbreak of Bundibugyo Ebola, with over 250 people enrolled in a clinical trial testing the experimental antiviral obeldesivir. The trial, led by medical organisation ALIMA, aims to recruit nearly 1,000 participants who have recently come into contact with confirmed Ebola patients but have not developed symptoms. Volunteers are monitored for 21 days, the period when symptoms can emerge after exposure.
The World Health Organization (WHO) is sponsoring the PARTNERS trial in Congo, evaluating the monoclonal antibody MBP134 and the antiviral remdesivir. Researchers are also studying whether combining the two medicines can improve survival. The trial is being coordinated by Congo's National Institute of Biomedical Research, the Institute of Tropical Medicine in Belgium and the University of Oxford.
WHO experts have identified another monoclonal antibody, Maftivimab, as a candidate requiring clinical evaluation against Bundibugyo virus. In the United Kingdom, scientists at the University of Oxford have launched the world's first human trial of a vaccine specifically designed against Bundibugyo ebolavirus. The vaccine, ChAdOx1 BDBV, uses the same platform technology behind the Oxford-AstraZeneca COVID-19 vaccine.
The UK Phase 1 trial is testing the vaccine in healthy adults, an early-stage safety and immunogenicity study to establish whether the vaccine is safe and triggers an immune response. WHO experts have identified a second candidate, the single-dose rVSV Bundibugyo vaccine being developed by the International AIDS Vaccine Initiative, as a promising option. However, its development could take several months before it is ready for clinical evaluation.
Another candidate, ChAdOx1 Bundibugyo, developed by Oxford University and the Serum Institute of India, has been prioritised for further development. There is also the Ervebo vaccine, already licensed against Zaire ebolavirus, being studied because Bundibugyo is a different Ebola species. Whether the vaccine can protect against the virus driving the current Congo outbreak remains uncertain.
WHO has stressed that Ervebo is not licensed specifically against the Bundibugyo virus and that evidence of cross-protection remains limited and inconclusive. Its use in Congo is therefore being evaluated within research settings. The current outbreak has exposed a gap in Ebola preparedness: vaccines and treatments exist for some Ebola viruses, but Bundibugyo virus entered the crisis without a licensed vaccine or approved specific treatment.
As Kenya tightens response efforts, Duale stated that there is no Ebola in Kenya, while the WHO warned of rising Ebola threat. Kenya is among high-risk countries for Ebola spread, according to the CDC.
Key points
- Over 250 people enrolled in clinical trial testing obeldesivir against Bundibugyo Ebola virus
- WHO-sponsored PARTNERS trial evaluating monoclonal antibody MBP134 and antiviral remdesivir
- University of Oxford launches world's first human trial of vaccine against Bundibugyo ebolavirus
