The Race to Develop a Bundibugyo Ebola Virus Vaccine

In close succession, two separate candidates for an Ebola vaccine to tackle the deadly Bundibugyo strain have entered Phase 1 clinical trials.

It provides a ray of hope amid an Ebola outbreak in the DR Congo (DRC) which, according to DRC public health estimates, has seen a recorded 3,973 cases and 1,801 deaths recorded as of 4 August 2026.

Oxford University researchers are behind one of the trials, while Moderna is advancing the other in Canada, with both leveraging technology used to develop the COVID-19 vaccine.

In addition, a clinical trial of a potential post-exposure prophylaxis medicine is underway, led by the DRC’s National Institute for Biomedical Research, supported by an international consortium of research and outbreak-response partners.

Moderna leads the pharma industry’s efforts

Moderna announced clinical trials began on 4 August 2026.

The vaccine candidate draws on Moderna's mRNA platform — the same technology that proved capable of rapid development, scalability and worldwide rollout during the COVID-19 pandemic. 

It also builds on work Moderna has already put into filoviruses, the family of viruses that includes Ebola.

"Vaccinating the first participants with mRNA-1469 marks an important milestone in advancing a vaccine candidate against Bundibugyo ebolavirus, for which no approved vaccine currently exists," says Stéphane Bancel, Chief Executive Officer of Moderna. 

The programme sits within Moderna's partnership with the Coalition for Epidemic Preparedness (CEPI), which has pledged up to US$50m toward preclinical work and the Phase 1 trial.

"We are grateful to CEPI, Health Canada, the investigators and study participants for their contributions to advance this work," continues Stéphane.

That funding also covers scaling up manufacturing of trial doses alongside early-stage clinical work, a move designed to enable larger Phase 2 and Phase 3 trials to launch quickly should the Phase 1 data hold up.

"Getting Moderna's vaccine candidate into a Phase 1 trial this rapidly is a major step forward in the fight against this deadly outbreak," says Dr. Richard Hatchett, CEO of CEPI.

Using the COVID vaccine template

On 13 July 2026, Oxford University announced that researchers were initiating the first clinical trials for the Bundibugyo strain.

The trial will test the safety of the ChAdOx1 BDBV vaccine and the immune response it triggers in 50 healthy adults between 18 and 55. 

Volunteer recruitment has begun, and the first recruits have received doses of the vaccine candidate.

To get the study up and running quickly and push the vaccine candidate into clinical testing, the Serum Institute of India (SII) has manufactured and stockpiled roughly 620,000 doses.

Scientists at the University of Oxford's Oxford Vaccine Group and Pandemic Sciences Institute developed the vaccine candidate using the same viral vector platform behind the Oxford/AstraZeneca COVID-19 vaccine – a vaccine credited with saving over six million lives in its first year alone.

Professor Katrina Pollock, MRC Clinician Scientist in Vaccinology and Chief Investigator at the Oxford Vaccine Group, says: 'Launching this first-in-human study of a Bundibugyo ebolavirus vaccine is an important milestone for the programme and the culmination of a significant effort by teams across vaccine development, manufacturing and clinical testing. 

“We are focused on delivering a rigorous Phase 1 trial, to the highest standard of care, to evaluate the safety, tolerability and immune responses generated by the vaccine.”

A race against time

As both vaccine candidates move through the clinical trial process, the search for a safe, effective vaccine candidate is a pressing race against time.

The current outbreak is the second-largest in history, only behind the 2014-2016 West African epidemic, which claimed 11,325 lives and infected over 28,600 people.

With concerns among health officials that the virus could be mutating, the vital work by Moderna and Oxford University researchers is of paramount importance in protecting global health.

"This fast-growing epidemic is already the second-largest Ebola outbreak in history, and cases are rising more quickly than they did in the 2014 - 2016 West Africa epidemic, which remains the largest on record. 

"Every day matters, and every vaccine candidate in clinical trials gives us another shot at getting a safe, effective vaccine to the people who need it as swiftly as possible," says Richard.