The World Health Organization has identified a series of experimental treatments and vaccines to be tested in clinical trials as health authorities respond to the ongoing Bundibugyo Ebola outbreak in Central Africa.
In recommendations issued on Thursday, the WHO said three experimental treatments should be prioritized for evaluation against the Bundibugyo strain of Ebola, which currently has no approved therapies or vaccines.
The agency highlighted Mapp Biopharmaceutical’s MBP134, Regeneron’s monoclonal antibody treatment maftivimab, and Gilead Sciences’ antiviral drug remdesivir as the leading treatment candidates.
A member of Uganda People’s Defence Force directs people , after Uganda closed its borders with the Democratic Republic of Congo, as authorities intensify efforts to contain a new Ebola outbreak caused by the Bundibugyo virus strain, at the Mpondwe border post, in Kasese district, Uganda, May 28, 2026. REUTERS/Abubaker Lubowa
The WHO said the therapies, along with several vaccine candidates, should be tested in clinical trials to generate urgently needed data on their effectiveness against the outbreak.
The move comes as Ebola cases continue to spread in the Democratic Republic of Congo, with additional infections also reported in neighboring Uganda.
Regeneron said supplies of maftivimab are already available in the Democratic Republic of Congo and could be used immediately for treatment or as part of clinical studies if requested by the WHO.
For prevention efforts, the WHO identified Gilead’s experimental oral antiviral obeldesivir as a priority option for post-exposure treatment among people who have come into contact with confirmed Ebola patients. The agency noted that the drug’s effectiveness would depend heavily on successful contact tracing operations.
Children run alongside a woman on her tricycle, after Uganda closed its borders with the Democratic Republic of Congo, as authorities intensify efforts to contain a new Ebola outbreak caused by the Bundibugyo virus strain, at the Mpondwe border post, in in Kasese district, Uganda, May 28, 2026. REUTERS/Abubaker Lubowa
Among vaccine candidates, the WHO described a single-dose vaccine known as rVSV Bundibugyo, developed by the International AIDS Vaccine Initiative, as the most promising option currently under development.
However, the organization said the vaccine is unlikely to be ready for trials for another seven to nine months.
A second candidate, ChAdOx1 Bundibugyo, developed by Oxford University and the Serum Institute of India, could potentially enter testing within two to three months, although additional animal studies are still required.
The WHO also reviewed the potential use of Merck’s Ervebo vaccine, currently the only licensed Ebola vaccine. However, the agency advised that it should not be deployed outside research settings because evidence of its effectiveness against the Bundibugyo strain remains limited and inconclusive.
FILE PHOTO: An advocacy poster against the spread of Ebola virus is placed along the walkway at the Platinum Medical Centre, as aid agencies intensify efforts to contain a new Ebola outbreak involving the Bundibugyo Virus in Kampala, Uganda, May 26, 2026. REUTERS/Abubaker Lubowa/File Photo
WHO advisors additionally recommended exploring combination therapies using monoclonal antibodies together with remdesivir.
The agency said it is working alongside authorities in Congo and Uganda, as well as partners including the Africa Centres for Disease Control and Prevention, to design and implement the clinical trials under strict ethical standards.
The Bundibugyo strain is considered rare, and the WHO has described the current outbreak as the third-largest recorded outbreak involving the virus variant.
