HHS Cancels Millions in Pandemic Influenza mRNA Vaccine Development Grants

The US Department of Health and Human Services (HHS) has announced the cancellation of a series of grants for Moderna’s late-stage development of pre-pandemic influenza vaccines, including against H5N1 avian influenza, also known as bird flu, according to a news release from Moderna. This comes as the company announced positive interim data from a phase 1/2 clinical trial (NCT05972174) of mRNA-1018, a vaccine candidate targeting the H5 avian flu virus subtype, with significant efficacy and tolerable safety.^1,2

Under the leadership of HHS Secretary Robert F. Kennedy Jr., the Department is making numerous changes to policies on vaccines. | Image Credit: © Tada Images - stock.adobe.com

"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," Stéphane Bancel, CEO of Moderna, said in the news release. “These clinical data in pandemic influenza underscore the critical role mRNA technology has played as a countermeasure to emerging health threats."¹

According to reporting by NBC News, NPR, and Pharmacy Times^®, the grants included a $176 million award in July 2024, followed by a $590 million grant in January 2025. The grants, awarded through the Rapid Response Partnership Vehicle (RRPV) Consortium with funding from the Biomedical Advanced Research and Development Authority (BARDA), were intended to accelerate the development of mRNA-based pandemic influenza vaccines. The HHS leads the Administration for Strategic Preparedness and Response (ASPR), which is designed to facilitate research and stockpile resources in the event of major public health threats.^3-6

When Pharmacy Times reached out for comment on the impacts this announcement could have on further influenza vaccine development and any background the company might have on HHS’ decision, a representative from Moderna referred to the statement from Bancel. When asked if there were future actions the company was anticipating from HHS, the Moderna representative deferred to HHS for comment.

In the phase 1/2 study of Moderna’s 2-dose mRNA-1018 vaccine regimen, which enrolled approximately 300 healthy adults aged 18 years and older, individuals demonstrated a significant increase in immunity from baseline to follow-up at day 43. Preexisting immunity among the participants was minimal, as only 2.1% of individuals indicated hemagglutination inhibition (HAI) antibody titers of 1:40 or more, which is an HAI titer considered to correlate with strong protection, according to the investigators. At the day 43 follow-up point, 3 weeks following the second vaccination, 97.8% of participants demonstrated titers of 1:40 or more, with a 44.5-fold increase from baseline.¹

Critically, mRNA-1018 was generally well-tolerated among participants, and there were no dose-limiting tolerability concerns observed by the investigators. A majority of solicited adverse reactions were grade 1 or 2 in nature, and notably, they did not increase significantly with the number of doses administered or between first and second doses of the vaccine, according to the investigators.¹

Andrew Nixon, HHS communications director, said in a statement released to CNN, STAT, and other news organizations that HHS “concluded that continued investment in Moderna’s H5N1 mRNA vaccine was not scientifically or ethically justifiable,” alleging that mRNA technology “remains under-tested” and that “legitimate safety concerns” regarding the technology were hidden from the public. This is despite extensive research and investigation into mRNA vaccines, which have found that these vaccines are highly effective and safe for patients.^7-9

The grant cancellations come at a pivotal point, as H5N1 influenza continues to spread through poultry through outbreaks in all 50 states. According to the CDC, there have been 70 human cases of H5N1 in the United States since the outbreak began, and 1 death has been reported. With fears of a further outbreak and possible human-to-human transmission, the announcement of Moderna’s grant cancellation for mRNA-1018 could strike a major blow in efforts to prepare and counter the virus.¹⁰

As the landscape of mRNA vaccination remains fluctuating, pharmacists should stay aware of updates and future announcements from HHS and be prepared to counsel patients on major changes to vaccine composition or schedules.

REFERENCES

1. Moderna. Moderna announces an update on investigational pandemic influenza program. News Release. Released May 28, 2025. Accessed May 30, 2025. https://investors.modernatx.com/news/news-details/2025/Moderna-Announces-Update-on-Investigational-Pandemic-Influenza-Program-/default.aspx

2. ClinicalTrials.gov. A Study of mRNA-1018 Pandemic Influenza Candidate Vaccines in Healthy Adults. National Library of Medicine. Last Updated August 9, 2024. Accessed May 30, 2025. https://clinicaltrials.gov/study/NCT05972174?rank=1

3. Gerlach A. US Department of Health and Human Services grants $590 million to accelerate H5N1 mRNA vaccine development. Pharmacy Times. Published January 20, 2025. Accessed May 30, 2025. https://www.pharmacytimes.com/view/us-department-of-health-and-human-services-grants-590-million-to-accelerate-h5n1-mrna-vaccine-development

4. The Associated Press. Trump administration cancels $766 million Moderna contract to fight future pandemics including bird flu. NBC News. Published May 29, 2025. Accessed May 30, 2025. https://www.nbcnews.com/health/health-news/trump-administration-cancels-766-million-moderna-contract-fight-future-rcna209707

5. Stein R. Trump administration cancels plans to develop a bird flu vaccine NPR. Published May 28, 2025. Accessed May 30, 2025. https://www.npr.org/2025/05/28/nx-s1-5414642/trump-vaccine-bird-flu-mrna

6. Moderna. Moderna announces updates on pandemic influenza program. News Release. Released January 17, 2025. Accessed May 30, 2025. https://news.modernatx.com/news/news-details/2025/Moderna-Announces-Updates-on-Pandemic-Influenza-Program/default.aspx

7. Dillinger K. HHS cancels $590 million contract with Moderna for bird flu vaccine. CNN. Published May 28, 2025. Accessed May 30, 2025. https://www.cnn.com/2025/05/28/health/hhs-moderna-bird-flu-vaccine

8. Branswell H, Herper M. HHS cancels nearly $600 million Moderna contract on vaccines for flu pandemics. STAT. Published May 28, 2025. Accessed May 30, 2025. https://www.statnews.com/2025/05/28/moderna-flu-vaccine-development-cancelled-by-hhs-mrna-platform-offers-speedy-pandemic-response/

9. Jamous YF, Alhomoud DA. The safety and effectiveness of mRNA vaccines against SARS-CoV-2. Cureus. 2023;15(9):e45602. doi:10.7759/cureus.45602

10. CDC. H5 bird flu: Current situation. Last updated May 30, 2025. Accessed May 30, 2025. https://www.cdc.gov/bird-flu/situation-summary/index.html