Moderna starts H5N1 trial
- Moderna has begun a large late‑stage human trial of an mRNA H5N1 bird flu vaccine today. (finance.yahoo.com) - Reports call this the first late‑stage mRNA bird‑flu trial, restarted after U.S. funding was lost. (independent.co.uk) - Officials say the trial responds to a 'real possibility' of human threat and uses COVID‑era mRNA technology. (timesofindia.indiatimes.com)
Messenger RNA vaccines use genetic instructions to teach the body to recognize a virus, and Moderna has now started a Phase 3 human trial of an H5 bird flu shot in the U.S. and U.K. (accessnewswire.com) Moderna said on April 21 that the first participants had been dosed in the late-stage study of mRNA-1018, an investigational vaccine aimed at H5 pandemic influenza. The trial is expected to enroll about 4,000 healthy adults age 18 and older. (accessnewswire.com) The study is testing two things that decide whether a vaccine can move toward approval: safety and immunogenicity, which means whether it triggers an immune response. Moderna’s earlier Phase 1/2 study enrolled 1,504 adults from July 2023 to July 2024 to generate the data needed to pick an H5 candidate for this larger trial. (clinicaltrials.gov) H5N1 is a bird flu virus that mostly spreads in animals, but health agencies are tracking it because spillovers into mammals and occasional human infections keep happening. The Centers for Disease Control and Prevention said on March 6 that H5 bird flu is widespread in wild birds worldwide and is causing outbreaks in poultry and U.S. dairy cows, with sporadic human cases in exposed workers. (cdc.gov) The Centers for Disease Control and Prevention still says the current public-health risk to the general population is low. In Britain, the UK Health Security Agency said the virus continues to evolve and spread in birds and other animal hosts, while warning that it could adapt to spread from person to person. (cdc.gov) (accessnewswire.com) The program nearly stalled last year after the U.S. government pulled back funding. Health and Human Services announced on August 5, 2025 that it was winding down Biomedical Advanced Research and Development Authority support for mRNA vaccine development, after Moderna had already lost pandemic-flu funding in May 2025. (hhs.gov) (healio.com) That canceled support totaled $766 million, including $176 million awarded in 2024 and another $590 million added in January 2025 for pandemic influenza work, according to reporting and company disclosures. Moderna said interim Phase 1/2 data in about 300 adults showed a rapid and durable immune response, while HHS said the project did not meet its standards for continued federal investment. (biopharmadive.com) (healio.com) The trial restarted with different backing. The Coalition for Epidemic Preparedness Innovations, or CEPI, said in December 2025 that it would invest up to $54.3 million to support the pivotal Phase 3 study and help push mRNA-1018 toward licensure. (cepi.net) If the vaccine works, Moderna said regulatory filings would also lean on data from its separate seasonal flu vaccine program, mRNA-1010, which has already been accepted for review in the U.S., European Union, Canada and Australia. Moderna also said that, if licensed during a flu pandemic, it would reserve 20% of H5 manufacturing capacity for low- and middle-income countries at affordable prices under its CEPI agreement. (accessnewswire.com) For now, the new study is a preparedness test, not a response to sustained human-to-human spread. The next marker is whether this 4,000-person trial can show that an mRNA bird flu vaccine is safe and produces the immune response regulators want to see. (accessnewswire.com)
