NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has initiated a preliminary human trial for 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 trial represents the vaccine’s first application in human subjects. The World Health Organization has classified the Congo outbreak as a global public health emergency.
Approximately 80 healthy adults are expected to participate in the Phase 1 trial at three sites across Canada. The investigators will assess the vaccine’s safety, tolerability, and capacity to elicit an immune response. The purpose of this early-phase study is not to establish the vaccine’s efficacy in preventing Ebola infection but to evaluate safety and determine appropriate dosage levels before progressing to larger clinical trials. The Coalition for Epidemic Preparedness Innovations has allocated up to $50 million to support testing, manufacturing efforts, and additional research doses.
WHO reported 3,605 confirmed cases and 1,587 deaths in DR Congo up to July 30, with at least 651 recoveries by that date. The latest figures released on August 4 indicate over 3,800 cases and more than 1,700 fatalities. Health authorities identified infections in 49 health zones spanning five provinces, with Ituri remaining the outbreak’s epicenter, accounting for roughly 88% of confirmed cases.
Outbreak underscores absence of licensed vaccine
The ongoing epidemic involves Bundibugyo ebolavirus, one of several species within the Ebola virus family. Currently, there is no approved vaccine or targeted treatment for this particular strain. Existing licensed Ebola vaccines are designed to combat Zaire ebolavirus, which causes a different disease form. Historically, Bundibugyo ebolavirus has triggered previous outbreaks in Uganda and DR Congo, with 17 outbreaks recorded since its initial identification in 1976.
Transmission occurs through direct contact with infected blood, body fluids, tissues, or contaminated materials. To contain the spread, public health teams have ramped up testing, contact tracing, treatment, and infection control measures throughout affected regions. By July 30, authorities had listed 17,863 contacts for monitoring. WHO has also documented 151 confirmed cases among healthcare workers, including 44 deaths. Ongoing conflict, population displacement, and assaults on health facilities have hindered efforts to access and treat patients in several communities.
Additional vaccine candidates progress in development
This Moderna initiative follows a Phase 1 trial launched by the University of Oxford in the UK, with the first dose 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 approximately 620,000 doses of the Oxford vaccine and has supplied 4,000 investigational doses for clinical testing.
Both programs 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. One was developed by IAVI with manufacturing led by Hilleman Laboratories, while the other was created by Public Health Vaccines. At present, none of these vaccines have received approval for public use. The WHO emphasizes that ongoing efforts in surveillance, laboratory diagnostics, patient care, safe burials, and community engagement remain crucial components of the outbreak response.