NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has initiated a preliminary clinical trial for a vaccine targeting Bundibugyo ebolavirus. This development comes as an outbreak intensifies in the Democratic Republic of the Congo. The first dose of the mRNA-1469 vaccine was administered to a volunteer on August 3 in Truro, Nova Scotia. This marks the vaccine’s debut in human testing. The World Health Organization has declared the Congolese outbreak an international public health emergency.
The Phase 1 trial will include approximately 80 healthy adults across three sites in Canada. Researchers aim to evaluate the vaccine’s safety, tolerability, and ability to stimulate an immune response. The study does not intend to demonstrate the vaccine’s effectiveness in preventing Ebola infection. Early-stage trials primarily focus on safety and dosage, laying the groundwork for larger subsequent studies. 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 as of July 30. By that date, at least 651 patients had recovered. Updated data released on August 4 indicated the case count had surpassed 3,800, with deaths exceeding 1,700. Health officials identified infections across 49 health zones in five provinces. Ituri remained the epicenter, accounting for roughly 88% of confirmed cases.
Outbreak exposes the absence of an approved vaccine
The ongoing epidemic involves Bundibugyo ebolavirus, one among several species within the Ebola virus family. Currently, no vaccine or specific treatment has been approved for this particular species. Existing licensed Ebola vaccines are designed to target Zaire ebolavirus, which causes a different form of the disease. Historically, Bundibugyo ebolavirus has triggered outbreaks in Uganda and DR Congo. Since the virus was first identified 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 scaled up testing, contact tracing, treatment, and infection control efforts across affected regions. As of July 30, officials had listed 17,863 contacts for monitoring. The WHO also reported 151 confirmed infections among healthcare workers, including 44 fatalities. Ongoing armed conflict, population displacement, and attacks on health facilities have hindered access to patients in several communities.
Additional vaccine candidates progress in development
Following Moderna’s efforts, the University of Oxford in Britain launched another Phase 1 trial. The first dose of their candidate was administered on July 24. This vaccine utilizes the ChAdOx1 platform, whereas Moderna’s version employs messenger RNA technology. The Serum Institute of India produced the Oxford vaccine and assembled a stockpile of about 620,000 doses. It also supplied 4,000 investigational doses for clinical research.
Both programs are supported by CEPI as part of a broader initiative 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. The other was created by Public Health Vaccines. None of these candidates currently has approval for public use. WHO emphasizes that surveillance, laboratory diagnosis, patient care, safe burials, and community engagement continue to be vital components of the outbreak response.