NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has initiated a preliminary human trial of a vaccine targeting Bundibugyo ebolavirus amid a rising outbreak in the Democratic Republic of the Congo. On August 3, in Truro, Nova Scotia, a volunteer received the inaugural dose of the mRNA-1469 vaccine. This trial represents the vaccine’s initial application in human subjects. The World Health Organization has declared the Congolese outbreak an international public health emergency.
Approximately 80 healthy adults will participate in the Phase 1 trial across three locations in Canada. Researchers will evaluate the vaccine’s safety, tolerability, and capacity to induce an immune response. It is important to note that the trial does not aim to demonstrate the vaccine’s effectiveness in preventing Ebola infection. Early-phase studies primarily assess safety and dosage before progressing to larger-scale testing. 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 through July 30, with at least 651 recoveries noted by that date. Updated figures on August 4 indicated cases exceeding 3,800 and deaths surpassing 1,700. Health authorities identified infections across 49 health zones in five provinces, with Ituri remaining the outbreak’s epicenter, accounting for roughly 88% of confirmed cases.
Outbreak underscores absence of an approved vaccine
The current epidemic involves Bundibugyo ebolavirus, one of several species within the Ebola virus family. To date, no licensed vaccine or targeted treatment exists for this particular strain. The approved Ebola vaccines are directed at Zaire ebolavirus, which causes a different form of the disease. Historically, Bundibugyo ebolavirus has caused earlier outbreaks in Uganda and DR Congo, with the country experiencing 17 Ebola outbreaks since the virus was first identified in 1976.
The virus transmits through direct contact with infected blood, body fluids, organs, or contaminated materials. In response, public health teams have intensified efforts in testing, contact tracing, treatment, and infection control across affected regions. By July 30, officials had monitored 17,863 contacts. WHO also reported 151 confirmed infections among health workers, including 44 fatalities. Ongoing armed conflict, population displacement, and assaults on healthcare facilities have complicated efforts to reach and treat patients in multiple communities.
Additional vaccine candidates advance in development
Following Moderna’s trial, a separate Phase 1 study was launched by the University of Oxford in the UK, with the first dose administered on July 24. This vaccine utilizes the ChAdOx1 platform, whereas Moderna’s candidate employs 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 research.
Both programs are supported by WHO through CEPI, as part of a broader initiative to develop vaccines against Bundibugyo Ebola. In addition, the organization backs two other candidates based on recombinant vesicular stomatitis virus technology—one developed by IAVI with manufacturing led by Hilleman Laboratories, and another by Public Health Vaccines. Currently, none of these candidates have received approval for general public use. WHO emphasizes that ongoing surveillance, laboratory diagnostics, patient care, safe burial practices, and community engagement are crucial elements of the outbreak response.