NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has begun an early-phase trial of a vaccine targeting Bundibugyo ebolavirus amid the increasing outbreak in the Democratic Republic of the Congo. On August 3, a volunteer in Truro, Nova Scotia, received the initial dose of the mRNA-1469 vaccine. This trial represents the first time the vaccine has been administered to humans. The World Health Organization has officially declared the Congolese outbreak an international public health emergency.
Approximately 80 healthy adults will participate in the Phase 1 study conducted at three locations in Canada. Investigators will evaluate the vaccine’s safety, tolerability, and its capacity to elicit an immune response. The study does not aim to establish the vaccine’s effectiveness in preventing Ebola infection. As is typical in early-stage research, the focus is on safety and dosage prior to larger-scale trials. The Coalition for Epidemic Preparedness Innovations has pledged up to $50 million to support testing, manufacturing, and additional research doses.
WHO reported 3,605 confirmed cases and 1,587 deaths in DR Congo through July 30. By that date, at least 651 patients had recovered. Updated statistics released on August 4 indicated cases had surpassed 3,800, with fatalities exceeding 1,700. Health officials identified infections across 49 health zones within five provinces. Ituri continued to be the outbreak’s epicenter, accounting for roughly 88% of confirmed infections.
Outbreak Reveals Absence of Approved Ebola Vaccine
The ongoing epidemic involves Bundibugyo ebolavirus, one among multiple species within the Ebola virus family. Currently, no approved vaccine or targeted treatment exists for this particular strain. Existing licensed Ebola vaccines primarily protect against Zaire ebolavirus, which causes a different clinical form. Historically, Bundibugyo ebolavirus has caused outbreaks in Uganda and DR Congo, with a total of 17 outbreaks recorded since researchers first identified the virus in 1976.
Transmission occurs via direct contact with infected blood, body fluids, organs, or contaminated materials. Public health teams have intensified efforts in testing, contact tracing, treatment, and infection control across affected zones. By July 30, officials had listed 17,863 contacts for monitoring. WHO also documented 151 confirmed infections among healthcare workers, including 44 fatalities. Ongoing armed conflict, population displacement, and assaults on health facilities have hindered access to patients in several communities.
Other Vaccines Progress in Clinical Development
Following Moderna’s trial, the University of Oxford in Britain initiated its own Phase 1 study, administering the first dose of its candidate on July 24. The Oxford vaccine is based on the ChAdOx1 platform, whereas Moderna’s approach uses messenger RNA technology. The Serum Institute of India produced the Oxford vaccine, creating a stockpile of approximately 620,000 doses and supplying 4,000 investigational doses for research purposes.
Both programs receive support from CEPI, which is committed to developing vaccines against Bundibugyo Ebola. The organization also backs two additional candidates using recombinant vesicular stomatitis virus technology, developed by IAVI with manufacturing led by Hilleman Laboratories, and another by Public Health Vaccines. None of these vaccines currently hold approval for public use. WHO emphasizes that surveillance, laboratory diagnosis, patient care, safe burials, and community engagement remain crucial components of the ongoing outbreak response.