HHS said it pulled funding for testing because the shots are “under-tested.”
Beth Mole – May 29, 2025 9:03 AM | 201

Credit: Digicom Photo/Science Photo Library via Getty
The Department of Health and Human Services—under the control of anti-vaccine advocate Robert F. Kennedy Jr.—has canceled millions of dollars in federal funding awarded to Moderna to produce an mRNA vaccine against influenza viruses with pandemic potential, including the H5N1 bird flu currently sweeping US poultry and dairy cows.
Last July, the Biden administration’s HHS awarded Moderna $176 million to “accelerate the development of mRNA-based pandemic influenza vaccines.” In the administration’s final days in January, HHS awarded the vaccine maker an additional $590 million to support “late-stage development and licensure of pre-pandemic mRNA-based vaccines.” The funding would also go to the development of five additional subtypes of pandemic influenza.
On Wednesday, as news broke that the Trump administration was reneging on the contract, Moderna reported positive results from an early trial of a vaccine targeting H5 influenza viruses. In a preliminary trial of 300 healthy adults, the vaccine candidate appeared safe and boosted antibody levels against the virus by 44.5-fold.
An HHS spokesperson said that the decision to cancel the funding—which would support thorough safety and efficacy testing of the vaccines—was because the vaccines needed more testing.
“This is not simply about efficacy—it’s about safety, integrity, and trust.” HHS spokesperson Andrew Nixon told The Washington Post. “The reality is that mRNA technology remains under-tested.”
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Nixon went on to claim that the Trump administration wouldn’t repeat the “mistakes of the last administration, which concealed legitimate safety concerns.” The accusation refers to mRNA-based COVID-19 vaccines, which were developed and initially released under the first Trump administration. They have since been proven safe and effective against the deadly virus.
Kennedy, a staunch anti-vaccine advocate, has unflaggingly made false claims about the safety and efficacy of mRNA COVID-19 vaccines. In 2021, Kennedy petitioned the Food and Drug Administration to revoke authorization for COVID-19 vaccines and refrain from issuing future approvals. In recent days, Kennedy has also restricted access to COVID-19 vaccines and unilaterally revoked recommendations for healthy children and pregnant people to get the vaccines.
The federal funding for pandemic influenza vaccines was awarded as health officials around the country, including federal officials, were closely monitoring the swift and unprecedented spread of H5N1 bird flu through US dairy cows, which also spread to 70 people and killed one. Under the Trump administration, regular updates on the outbreak have ceased, and experts fear that cases are going undocumented.
In a statement Wednesday, Moderna CEO Stéphane Bancel struck an optimistic note, saying the company would pursue other funding sources to continue moving forward.
“While the termination of funding from HHS adds uncertainty, we are pleased by the robust immune response and safety profile observed in this interim analysis of the Phase 1/2 study of our H5 avian flu vaccine, and we will explore alternative paths forward for the program,” he said. “These clinical data in pandemic influenza underscore the critical role mRNA technology has played as a countermeasure to emerging health threats.”