DR CONGO — Three new Ebola vaccines are being developed to address an outbreak of the Bundibugyo species of Ebola virus that has killed nearly 250 people. More than 1,000 suspected cases have been reported in the Democratic Republic of Congo, with nine confirmed cases in Uganda.
The outbreak stems from the Bundibugyo species, for which no approved vaccine currently exists. A vaccine is available for the Zaire species of Ebola, but it is not effective against Bundibugyo. This current strain has been observed in only two previous outbreaks, and the outbreak was detected only after spreading in a conflict zone with limited healthcare resources.
The International AIDS Vaccine Initiative (IAVI), Moderna, and the University of Oxford are each developing distinct vaccines targeting the Bundibugyo glycoprotein. IAVI is modifying its existing Zaire Ebola vaccine to address Bundibugyo, using a live, harmless virus engineered to carry the Ebola glycoprotein. Moderna is leveraging its mRNA technology, while Oxford is using vaccine technology deployed during the Covid pandemic. All three approaches aim to train the immune system to recognize the Bundibugyo virus.
“I think this is clearly threatening to be as severe an outbreak as that, if not even worse, and development of a vaccine, and other countermeasures, is clearly a priority,” said Mark Feinberg, head of IAVI. He added that he is “optimistic about the potential” of the IAVI vaccine. It would typically take seven to nine months to prepare for clinical trials, though efforts are underway to accelerate that timeline.
Stéphane Bancel, chief executive officer of Moderna, said, “We will move with urgency and scientific rigor to support the response and help bring a potential vaccine closer to the communities that need it most.” The University of Oxford’s vaccine is expected to be ready for clinical trials in two to three months, while IAVI’s candidate showed close to 100% protection in monkey studies.
Richard Hatchett, CEO of the Coalition for Epidemic Preparedness Innovations (CEPI), said, “With Bundibugyo virus spreading rapidly and no licensed vaccines, every day counts in the race against this deadly disease.” CEPI is funding early research for all three vaccine efforts. Differences in vaccine technologies may affect protection levels or dosing requirements, which will be evaluated in clinical trials.