DR Congo launches clinical trial testing Ebola vaccines as outbreak spreads

The World Health Organization has confirmed the launch of a clinical trial in the Democratic Republic of the Congo to evaluate vaccines against an ongoing Ebola epidemic.

Trial participants in Bunia, the capital of the northeastern Ituri province, have begun receiving doses of Ervebo, according to a statement posted on social media by WHO Director-General Tedros Adhanom Ghebreyesus. Ituri has served as the central zone of the current crisis, which represents the country's seventeenth recorded Ebola outbreak.

The existing Ervebo vaccine is authorized to fight the Zaire strain of Ebola. Researchers are now testing whether the shot provides cross-protection against the Bundibugyo species responsible for the present wave of infections. Tedros noted that the DRC-led initiative aims to assess the effectiveness of vaccines developed to target the Bundibugyo virus.

Named the Tumaini trial, the project utilizes a single structure designed to test the safety, immune response, and overall efficacy of several potential vaccines. The study relies on ring vaccination, a method that inoculates close contacts facing high exposure risks. Unlike many earlier clinical programs, this study incorporates pregnant women and adolescents aged 12 and above to build data for groups typically omitted from such research.

Health officials intend to add two other candidate vaccines formulated specifically for the Bundibugyo strain into the trial soon. These include an adenoviral vector vaccine created by the University of Oxford and an mRNA-based option developed by the United States biotechnology firm Moderna. Both candidates have received backing from the Coalition for Epidemic Preparedness Innovations and are moving through early-stage evaluations.

WHO emergencies director Chikwe Ihekweazu explained that the study was organized to provide the necessary scientific evidence to see whether the vaccines can shield vulnerable populations from infection.

The Democratic Republic of the Congo officially declared the outbreak in May, and it has since escalated into the nation's deadliest on record. Authorities have counted over 9,700 cases and more than 4,600 fatalities.

The virus has also crossed borders into three other African nations across the eastern, central, and western regions, marking the widest geographic reach of any Ebola outbreak ever recorded on the continent. The escalating spread previously prompted the WHO to declare the situation a public health emergency of international concern.