International AIDS Vaccine Initiative (IAVI), a nonprofit scientific research organisation, has vaccinated the first participants with its investigational Ebola Sudan vaccine in Uganda.
The trial, led by the World Health Organization (WHO), is being held at the Makerere University Lung Institute in Kampala. WHO prioritised IAVI’s vaccine to support Uganda’s Ebola outbreak response.
The vaccine candidate was prepositioned in the country as part of a global collaboration.
According to IAVI, Uganda’s sixth Ebola Sudan outbreak poses a 50% fatality risk. No licensed vaccines or treatments exist for this Category A priority pathogen.
Existing Ebola Zaire vaccines do not protect against Ebola Sudan.
Uganda’s Ebola outbreak started recently with a health worker’s death in Kampala. Since then, 45 contacts have been identified.
Close contacts are being prioritised for the ring vaccination trial due to high infection risk.
A recent study has confirmed ring vaccination’s effectiveness in containing Ebola outbreaks in the Democratic Republic of the Congo.
The vaccine used, which is Merck’s Zaire ebolavirus vaccine ERVEBO, shares the same rVSV viral vector platform as IAVI’s Ebola Sudan vaccine candidate. ERVEBO is licensed in over a dozen countries.
IAVI president and CEO Mark Feinberg said: “IAVI is grateful for the efforts that the WHO, the Ugandan government, and our public health partners in Uganda have made in enabling the rapid deployment of our investigational Ebola Sudan vaccine candidate to address the ongoing outbreak of Ebola Sudan in Uganda.
“We believe this clinical trial represents an important step toward evaluating the potential of IAVI’s vaccine to protect exposed individuals from Ebola Sudan infection as well as demonstrating its value as a safe, effective, and accessible new tool to include in comprehensive outbreak responses in the future.”
In 2023, IAVI began a Phase 1 clinical trial of its rVSV-based Ebola Sudan vaccine in healthy US adults at three dose levels.
Initial results showed that the vaccine was well-tolerated and triggered immune responses in all groups. These findings were shared in November 2024.
The nonprofit scientific research organisation is now planning a follow-up Phase 1 study in Africa.
rVSV, the backbone of IAVI’s Ebola Sudan vaccine, is also used in IAVI’s portfolio of emerging infectious disease (EID) candidates. This includes a Lassa virus vaccine, currently in Phase 2 trials in West Africa.
