Scientists are racing to develop four Ebola vaccines to tackle the outbreak in DR Congo, two of which could be ready for clinical trials in two months, the head of a global vaccine coalition told Semafor.

More than 500 cases of the Bundibugyo strain, for which there is no proven vaccine, have been reported in the outbreak, which is concentrated in eastern DR Congo.

Two of the experimental vaccines — one being developed by Oxford University scientists, and another by Moderna — harness technology used to create vaccines for COVID-19 and could be in trials by the end of summer, Richard Hatchett, CEO of the Coalition for Epidemic Preparedness Innovations, said.

Still, Hatchett cautioned, even if a vaccine performed well in clinical trials, it would take at least two more months to move to further trials and receive regulatory approval.

Emanuele Capobianco, director of global health security at GAVI, a global vaccine alliance, also warned in a separate interview that it was likely that it was “going to take several months, potentially years” to end the outbreak. He likened the current outbreak to the 2018 epidemic Zaire strain in eastern DR Congo which lasted two years, despite there being a vaccine for that strain.