Moderna began a large-scale clinical trial of an mRNA-based bird flu vaccine for humans on April 22, 2026, after the U.S. Department of Health and Human Services canceled previously committed funding for the project.
The trial involves thousands of participants across multiple countries
The Phase 3 study will enroll approximately 10,000 adults aged 18 and older in the United States, Europe, and Southeast Asia to evaluate the vaccine’s safety and efficacy against H5N1 avian influenza strains.
HHS withdrew $300 million in previously pledged support
Health and Human Services Secretary Robert F. Kennedy Jr.’s department canceled $300 million in funding that had been allocated to Moderna under pandemic preparedness initiatives, citing a reassessment of priorities.
Moderna is funding the trial independently using internal resources
The company stated It’s covering all trial costs through existing cash reserves and operational budgets, without additional government subsidies or external grants.
Public health officials warn of rising zoonotic spillover risk
Experts note increased H5N1 detection in dairy cattle and poultry farms globally, with over 500 human cases reported since 2020, though sustained human-to-human transmission remains rare.
The vaccine uses the same mRNA platform as Moderna’s COVID-19 shot
It encodes for the hemagglutinin protein of the H5N1 virus, designed to trigger an immune response without using live virus, similar to the technology deployed during the coronavirus pandemic.
Regulatory agencies are monitoring the trial closely
The U.S. Food and Drug Administration and the European Medicines Agency have granted fast-track designation to the vaccine candidate, which could accelerate review if results meet efficacy thresholds.
Why did HHS cancel the funding for the bird flu vaccine?
HHS stated the cancellation was part of a broader reassessment of public health spending priorities under Secretary Robert F. Kennedy Jr., though specific criteria were not detailed in the announcement.
When could the vaccine be available if the trial succeeds?
If the trial demonstrates sufficient safety and efficacy, Moderna could seek emergency use authorization as early as late 2027, though full approval would likely follow in 2028 or later depending on regulatory review timelines.