Moderna Launches mRNA Bird Flu Vaccine Trial as HHS Funding Ends, UK and US Begin Groundbreaking Studies for Pandemic Preparedness

Moderna has initiated a Phase 3 clinical trial for its investigational mRNA vaccine targeting the H5N1 avian influenza virus, marking a significant step in pandemic preparedness efforts amid evolving global health threats.

The vaccine, designated mRNA-1018, utilizes the same messenger RNA technology employed in Moderna’s COVID-19 vaccines and is designed to instruct the body to produce specific viral proteins to train the immune system against potential infection.

According to the trial announcement, approximately 4,000 participants will be enrolled across the United Kingdom and the United States, with the study expected to run for seven months. Participants will receive two doses administered three weeks apart.

In the UK, 3,000 individuals are set to receive the vaccine at 26 sites spanning England and Scotland, with half of the participants aged over 65. The trial is backed by the National Institute for Health and Care Research (NIHR) and sponsored by Moderna.

Early trial data indicated that the vaccine candidate was generally well tolerated, with most side effects described as mild to moderate and no safety concerns identified during initial testing phases.

The A(H5N1) strain has demonstrated increasing geographic spread in recent years, affecting not only avian populations but also mammalian species including mink, marine mammals, and dairy cattle in the United States. Human cases have been reported among farm workers with direct exposure to infected animals.

While health authorities maintain that sustained human-to-human transmission of the current H5N1 strain remains uncommon, experts emphasize the importance of proactive vaccine development given the virus’s ongoing evolution and potential pandemic risk.