HHS Quietly Advances Marburg and Sudan Ebolavirus Vaccine Development Despite Kennedy's Vaccine Skepticism
Key Insights
The Department of Health and Human Services (search) announced plans to fund development of vaccines against Marburg virus (search) and Sudan ebolavirus (search), two hemorrhagic fevers with fatality rates up to 90 percent.
BARDA (search) posted a pre-solicitation notice on June 27 seeking vaccine candidates that have completed Phase 2 clinical trials, with funding to support Phase 3 studies and FDA licensure.
The announcement comes as Health Secretary Robert F. Kennedy Jr. dismantled the Advisory Committee for Immunization Practices and backs cuts to infectious disease research.
The Department of Health and Human Services (search) quietly announced last month its intention to fund the development of vaccines against Marburg virus (search) and Sudan ebolavirus (search), two viruses it considers "material threats to national health security." The move signals that even as Health Secretary Robert F. Kennedy Jr. fires the country's top vaccine committee and backs cuts to infectious disease research, the department remains aware of the dangers a hobbled public health infrastructure would pose to U.S. biosecurity.
The pre-solicitation notice for the two vaccines was posted to a government contracting website on June 27 by the Biomedical Advanced Research and Development Authority (BARDA (search)), an HHS center that partners with the biomedical industry to develop bioterrorism countermeasures.
Targeting Deadly Hemorrhagic Fevers
BARDA (search) is targeting the Marburg virus (search) and Sudan ebolavirus (search) with the proposed vaccines. Both are hemorrhagic fevers in the same family as the Ebola virus (search), characterized by severe symptoms including uncontrolled bleeding and high fatality rates. According to the pre-solicitation notice, infections with these viruses "can lead to case fatality rates of up to 90 percent."
An HHS spokesperson confirmed that "BARDA (search) plans to invest Project BioShield funds to support the advanced development and potential FDA licensure of monovalent vaccines" for the Marburg and Sudan viruses. "These viruses cause deadly hemorrhagic fevers, and no FDA-approved vaccines or treatments currently exist," the spokesperson wrote.
Clinical Development Requirements
Eligible vaccine candidates must be in or have completed Phase 2 clinical trials. BARDA (search) funding may support Phase 3 studies, CMC development, U.S.-based manufacturing, nonclinical studies, assay development, and post-marketing studies required for licensure. The acquisition also includes options for future dose procurement as needed.
Phase 3 clinical trials are the final testing step drugs must complete before FDA approval, and they generally take several years. BARDA (search) is currently funding Marburg and Sudan vaccines in development with the nonprofit Sabin Vaccine Institute (search), with both vaccines having entered clinical trials in the U.S. earlier this year.
Recent Outbreak History Drives Urgency
The immediate need for MARV and SUDV vaccines has been emphasized by recent outbreaks. BARDA (search) cites the SUDV outbreak in 2022 that resulted in 141 confirmed cases and 55 deaths. Additionally, a MARV outbreak in 2024 led to 66 confirmed cases and 15 deaths.
Cases of hemorrhagic fevers are rare in the U.S., but Africa has seen outbreaks of the Marburg and Sudan viruses every few years for decades. The worst hemorrhagic fever (search) outbreak to date was an Ebola outbreak in West Africa in the mid-2010s that infected over 28,000 people, with more than 11,000 deaths.
While two vaccines against Ebola are now commercially available, neither protect against the Marburg or Sudan viruses.
Vaccine Technology and Political Context
The Marburg and Sudan vaccines that BARDA (search) is currently developing aren't mRNA vaccines. Both use a technique called an adenovirus vector, which uses a modified version of a "common cold" virus to present proteins from the hemorrhagic viruses to the immune system and elicit an immune response.
The announcement comes amid significant changes at HHS under Kennedy's leadership. The vaccine-skeptical secretary recently disbanded the Advisory Committee for Immunization Practices, removing all 17 committee members and replacing them with several people who have also been critical of vaccines. Kennedy said his picks were "committed to evidence-based medicine, gold-standard science, and common sense."
Expert Perspectives
"It's almost notable in that it's not remarkable at all," one former ASPR official said of the announcement. "Maybe you give this administration some small bit of credit for not blowing everything up, or maybe BARDA (search) managed to do this under the radar."
Gigi Kwik Gronvall, a professor at Johns Hopkins University and biosecurity expert, noted that while hemorrhagic viruses could pose a biosecurity threat, she was far more concerned by the immediate threat posed by avian influenza (search). HHS recently cancelled funding for a candidate mRNA H5 avian influenza vaccine that was in development with Moderna.
"In an ideal world, we would do both because even though Marburg is not immediately important, it is a naturally occurring disease that is pretty devastating," Gronvall wrote. "It's preparing for that in advance of an actual crisis that biosecurity is all about."
Gronvall wondered if the pre-solicitation announcement flew under Kennedy's radar, noting: "It makes me wonder if this is something that was on auto pilot because they haven't exactly been encouraging of science-based approaches to dealing with any public health threats, especially those of a viral nature."