NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has initiated a preliminary human trial for a vaccine targeting Bundibugyo ebolavirus amid escalating cases in the Democratic Republic of the Congo. The first dose of the mRNA-1469 vaccine was administered on August 3 in Truro, Nova Scotia. This marks the vaccine’s initial testing in human subjects. The World Health Organization has declared the outbreak in Congo a global public health emergency.
The Phase 1 trial plans to recruit roughly 80 healthy adults across three locations in Canada. Researchers will assess the vaccine’s safety, tolerability, and capacity to stimulate an immune response. The study is not designed to establish the vaccine’s effectiveness in preventing Ebola infection. Early development phases focus on safety and dosage levels before progressing to larger-scale trials. The Coalition for Epidemic Preparedness Innovations has pledged 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, with at least 651 patients recovered by that date. Updated figures on August 4 indicated the cases had risen to over 3,800 and deaths to more than 1,700. Health officials identified infections across 49 health zones in five provinces, with Ituri remaining the outbreak’s epicenter, accounting for approximately 88% of confirmed cases.
Outbreak underscores absence of an approved vaccine
The ongoing epidemic involves Bundibugyo ebolavirus, one of several species within the Ebola virus family. Currently, no approved vaccine or specific treatment exists for this particular species. Existing licensed Ebola vaccines are aimed at Zaire ebolavirus, which causes a different form of the disease. Historically, Bundibugyo ebolavirus has caused outbreaks in Uganda and DR Congo, with 17 outbreaks recorded since the virus was first identified in 1976.
Transmission occurs through direct contact with infected blood, bodily fluids, organs, or contaminated materials. Efforts by health authorities have included expanded testing, contact tracing, treatment, and infection control measures across 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. Ongoing conflict, displacement, and attacks on health facilities have hindered access to patients in multiple communities.
Other vaccine candidates progress in development
Following Moderna’s effort, the University of Oxford in the UK has also initiated a Phase 1 study, with the first dose administered on July 24. Their vaccine utilizes the ChAdOx1 platform, contrasting Moderna’s messenger RNA approach. The Serum Institute of India has produced approximately 620,000 doses of the Oxford vaccine and supplied 4,000 investigational doses for research. CEPI supports both programs as part of a broader initiative to develop vaccines against Bundibugyo Ebola. The organization also backs two additional candidates based on recombinant vesicular stomatitis virus technology, developed by IAVI with manufacturing led by Hilleman Laboratories and another by Public Health Vaccines. None have obtained approval for public use. WHO emphasizes that surveillance, laboratory diagnosis, patient care, safe burials, and community engagement are vital components of the ongoing outbreak response.