NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has initiated a preliminary human trial of a vaccine targeting Bundibugyo ebolavirus amid escalating outbreaks 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 marks the vaccine’s first application in human subjects. The World Health Organization has officially declared the Congolese outbreak an international public health emergency.
The Phase 1 trial will involve approximately 80 healthy adults at three sites across Canada, where researchers will assess the vaccine’s safety, tolerability, and its capacity to induce an immune response. The primary goal is not to establish the vaccine’s efficacy in preventing Ebola infection but to evaluate safety and dosage. Early-stage testing emphasizes safety profiles and dosage optimization before progressing to larger clinical trials. The Coalition for Epidemic Preparedness Innovations has pledged up to $50 million to support testing, manufacturing, and supplementary research doses.
WHO reported 3,605 confirmed cases and 1,587 deaths in DR Congo through July 30, with 651 patients recovered. Updated statistics on August 4 indicated case numbers exceeding 3,800 and deaths surpassing 1,700. The outbreak has affected 49 health zones across five provinces, with Ituri remaining the epicenter, accounting for roughly 88% of confirmed infections.
Outbreak underscores lack of approved Ebola vaccine
The ongoing epidemic involves Bundibugyo ebolavirus, one of several species within the Ebola family. Currently, no approved vaccine or targeted treatment exists for this particular strain. Existing licensed Ebola vaccines are designed against Zaire ebolavirus, which causes a different form of the disease. Historically, Bundibugyo ebolavirus has triggered previous outbreaks in Uganda and DR Congo, with 17 outbreaks recorded since its identification in 1976.
The virus transmits through direct contact with infected blood, bodily fluids, organs, or contaminated materials. Health authorities have increased testing, contact tracing, treatment, and infection prevention efforts across affected regions. By July 30, they had monitored 17,863 contacts. WHO also reported 151 confirmed infections among healthcare workers, including 44 fatalities. Ongoing armed conflicts, population movements, and attacks on health facilities have hindered access to many communities.
Other vaccine efforts progressing
Following Moderna’s trial, the University of Oxford in the UK launched its own Phase 1 study, administering the first dose on July 24. The Oxford candidate uses the ChAdOx1 platform, contrasting with Moderna’s messenger RNA technology. The Serum Institute of India produced about 620,000 doses for stockpiling and provided 4,000 investigational doses for research purposes. CEPI supports both initiatives as part of broader efforts to develop vaccines against Bundibugyo Ebola. Additionally, two candidates based on recombinant vesicular stomatitis virus technology are in development—one by IAVI with manufacturing led by Hilleman Laboratories, and another by Public Health Vaccines—though neither is approved for public use. WHO emphasizes the importance of surveillance, lab diagnosis, patient care, safe burials, and community engagement as crucial components of the response to the outbreak.