DEMOCRATIC REPUBLIC OF THE CONGO — World Health Organization officials announced on June 24, 2026, that a clinical trial to test two drugs against the Bundibugyo ebolavirus will begin the following week. The trial will take place in the Democratic Republic of the Congo.

The clinical trial will evaluate Gilead Sciences' antiviral drug remdesivir and MappBio's monoclonal antibody MBP-134. The trial design tests whether remdesivir or MBP-134 is effective on its own against the Bundibugyo ebolavirus and if a combination of the two drugs shows greater effectiveness. Gilead Sciences supplied doses of remdesivir, and the United States government, through the Biomedical Advanced Research and Development Authority, supplied doses of MBP-134 for the trial.

There are currently no drugs or vaccines that have proven effective against the Bundibugyo species of Ebola. This species was first detected in 2007, and the current outbreak marks the third known instance involving the Bundibugyo species.

As of June 2026, nearly 1,100 cases of the Ebola outbreak have been confirmed in the Democratic Republic of the Congo, with over 275 deaths recorded. Neighboring Uganda has recorded 20 confirmed Ebola cases and two deaths.

The clinical trial is being conducted by a consortium that includes the Democratic Republic of the Congo's National Institute of Biomedical Research, ALIMA, the University of Oxford, and the World Health Organization. ALIMA, Doctors Without Borders, and Samaritan's Purse will be responsible for enrolling participants in the trial.

Vasee Moorthy, acting lead of the World Health Organization's R&D Blueprint group, discussed the participant numbers. Moorthy said, "It means that we are looking at around 1,000 [participants] that would need to be enrolled in the trial before we expect that there will be an answer about the safety and efficacy of any of these options."