NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has initiated an early-phase clinical trial of a vaccine targeting Bundibugyo ebolavirus as the outbreak in the Democratic Republic of the Congo continues to escalate. On August 3, a volunteer in Truro, Nova Scotia, received the inaugural dose of the mRNA-1469 vaccine. This marks the vaccine’s first application in human subjects. The World Health Organization has classified the Congolese outbreak as an international public health emergency.

The Phase 1 trial plans to recruit approximately 80 healthy adults across three sites in Canada. The primary goals are to assess the vaccine’s safety, tolerability, and capacity to elicit an immune response. The study is not designed to demonstrate the vaccine’s effectiveness in preventing Ebola infection. These early trials concentrate on safety and dosage levels prior to larger, more definitive studies. The Coalition for Epidemic Preparedness Innovations has allocated up to $50 million to fund testing, manufacturing, and additional research doses.
WHO reported 3,605 confirmed cases and 1,587 deaths in DR Congo as of July 30. By that date, 651 patients had recovered. Updated data released on August 4 indicates cases have surpassed 3,800 and fatalities are above 1,700. Health officials identified infections across 49 health zones within five provinces, with Ituri remaining the outbreak’s epicenter, accounting for roughly 88% of confirmed cases.
Outbreak exposes absence of an approved vaccine
The ongoing epidemic involves Bundibugyo ebolavirus, a member of the Ebola virus family. Currently, there is no licensed vaccine or targeted treatment for this specific species. Existing approved Ebola vaccines are designed for Zaire ebolavirus, which causes a different form of the disease. Historically, Bundibugyo ebolavirus has caused outbreaks in Uganda and DR Congo. Since its discovery in 1976, the country has experienced 17 Ebola outbreaks.
Transmission occurs through direct contact with infected blood, bodily fluids, organs, or contaminated materials. In response, public health teams have ramped up testing, contact tracing, treatment, and infection prevention measures across affected regions. By July 30, officials had identified 17,863 contacts for monitoring. WHO also documented 151 confirmed infections among healthcare workers, including 44 fatalities. Ongoing armed conflict, population displacement, and attacks on health facilities have hindered access to many communities.
Additional vaccine candidates progress in development
The Moderna trial follows a separate Phase 1 study initiated by the University of Oxford in the United Kingdom. The first dose of the Oxford candidate was administered on July 24. The Oxford vaccine employs the ChAdOx1 platform, whereas Moderna’s candidate utilizes messenger RNA technology. The Serum Institute of India has produced about 620,000 doses of the Oxford vaccine, including 4,000 investigational doses supplied for clinical research.
Both initiatives are supported by CEPI as part of a broader effort to develop vaccines against Bundibugyo Ebola. The organization also backs two other candidates based on recombinant vesicular stomatitis virus technology, developed by IAVI with manufacturing led by Hilleman Laboratories, and one by Public Health Vaccines. None of these vaccines have received approval for public use. WHO emphasizes that surveillance, laboratory diagnostics, patient management, safe burials, and community engagement are crucial elements of the ongoing outbreak response.
