NOVA SCOTIA, CANADA / RankWire.AI / – Moderna has commenced early human testing of a vaccine targeting Bundibugyo ebolavirus as the Democratic Republic of the Congo faces a growing outbreak. On August 3, in Truro, Nova Scotia, a volunteer received the initial dose of the mRNA-1469 vaccine. This marks the vaccine’s inaugural application in humans. The World Health Organization has classified the Congolese outbreak as an international public health emergency.
Approximately 80 healthy adults will participate in the Phase 1 trial at three Canadian sites. The focus of this research is to assess the safety, tolerability, and capacity of the vaccine to elicit an immune response. It does not aim to demonstrate the vaccine’s effectiveness in preventing Ebola infection. Early-phase studies primarily evaluate safety and dosage parameters before proceeding to larger-scale trials. 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 through July 30, with at least 651 recoveries recorded by that date. Updated data from August 4 indicated cases exceeding 3,800 and fatalities surpassing 1,700. Health officials identified infections across 49 health zones in five provinces, with Ituri remaining the outbreak’s epicenter, responsible for about 88% of confirmed cases.
Outbreak underscores the absence of an approved vaccine
The ongoing epidemic is caused by Bundibugyo ebolavirus, which belongs to the diverse Ebola virus family. Currently, there are no licensed vaccines or specific treatments targeting this particular species. Existing authorized Ebola vaccines are designed for Zaire ebolavirus, responsible for a different disease form. Historically, Bundibugyo ebolavirus has led to outbreaks in Uganda and DR Congo. Since its initial discovery in 1976, the country has experienced 17 Ebola outbreaks.
Transmission occurs through direct contact with infected blood, body fluids, organs, or contaminated materials. Public health teams have ramped up efforts in testing, contact tracing, treatment, and infection control measures across affected regions. As of July 30, officials had listed 17,863 contacts for monitoring. WHO also noted 151 confirmed infections among healthcare workers, including 44 fatalities. Ongoing armed conflicts, displacement, and attacks on health facilities have hindered access to patients in multiple communities.
Additional vaccine candidates progress in development
Following Moderna’s efforts, the University of Oxford in Britain initiated a Phase 1 study with the first dose administered on July 24. This vaccine employs the ChAdOx1 platform, contrasting with Moderna’s messenger RNA approach. The Serum Institute of India has produced the Oxford vaccine, assembling a stockpile of approximately 620,000 doses, and has supplied 4,000 investigational doses for clinical trials.
Both programs are supported by CEPI as part of an expanded initiative to develop vaccines against Bundibugyo Ebola. The organization also 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. Neither has received approval for public use. WHO emphasizes that surveillance, laboratory diagnosis, patient care, safe burial practices, and community engagement remain vital components of the outbreak response.