NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has initiated a preliminary human trial of a vaccine targeting Bundibugyo ebolavirus amid a rising outbreak in the Democratic Republic of the Congo. On August 3, in Truro, Nova Scotia, a volunteer received the initial dose of the mRNA-1469 vaccine. This trial represents the vaccine’s first application in humans. The World Health Organization has declared the Congolese outbreak an international public health emergency.
The Phase 1 trial plans to recruit approximately 80 healthy adults across three Canadian sites. The study aims to evaluate the vaccine’s safety, tolerability, and capacity to induce an immune response. It is not designed to determine whether the vaccine prevents Ebola infection. As with most early-stage trials, the focus is on safety and dosage before advancing to larger-scale testing. The Coalition for Epidemic Preparedness Innovations has allocated up to $50 million to fund testing, manufacturing efforts, and additional research doses.
WHO reported 3,605 confirmed cases and 1,587 deaths in DR Congo through July 30, with at least 651 recoveries. Updated data from August 4 indicate cases have surpassed 3,800 and deaths over 1,700. Infections have been identified in 49 health zones across five provinces, with Ituri remaining the outbreak’s epicenter, accounting for about 88% of confirmed cases.
Outbreak underscores absence of approved vaccine
The ongoing epidemic involves Bundibugyo ebolavirus, which is one of several species within the Ebola virus family. Currently, no approved vaccine or targeted treatment exists for this particular species. Existing licensed Ebola vaccines are designed for Zaire ebolavirus, which causes a different form of the disease. Historically, Bundibugyo ebolavirus has caused previous outbreaks in Uganda and DR Congo. Since the virus’s discovery in 1976, researchers have documented 17 Ebola outbreaks in the country.
Transmission occurs primarily through direct contact with infected blood, bodily fluids, organs, or contaminated materials. Health authorities have expanded efforts in testing, contact tracing, treatment, and infection prevention in affected regions. By July 30, officials had listed 17,863 contacts for monitoring. WHO also reported 151 confirmed infections among healthcare workers, including 44 fatalities. The situation is further complicated by armed conflicts, population movements, and attacks on health facilities, which hinder access to patients in several communities.
Other vaccine candidates move forward
Following Moderna’s efforts, the University of Oxford in the UK launched another Phase 1 trial, with the first dose administered on July 24. The Oxford candidate utilizes the ChAdOx1 platform, whereas Moderna’s vaccine is based on messenger RNA technology. The Serum Institute of India has produced the Oxford vaccine, assembling a stockpile of about 620,000 doses, and has supplied 4,000 investigational doses for research purposes.
Both programs receive support from CEPI as part of a broader initiative to develop Bundibugyo Ebola vaccines. The organization also funds two other candidates employing recombinant vesicular stomatitis virus technology—one developed by IAVI with manufacturing led by Hilleman Laboratories, and the other by Public Health Vaccines. None of these candidates currently have approval for public use. WHO emphasizes that surveillance, laboratory diagnosis, patient care, safe burials, and community engagement remain vital components of the outbreak response.