Moderna has shared positive results from a late-stage study of its seasonal influenza (flu) vaccine candidate mRNA-1010.
The phase 3 P304 trial randomised 40,805 adults aged 50 years and older to receive either a single dose of mRNA-1010 or a standard-dose licensed comparator, with a median follow-up of six months.
Moderna’s vaccine demonstrated a relative vaccine efficacy (rVE) in the overall study population that was 26.6% higher than the comparator.
Strong rVE was observed for each influenza strain contained in the vaccine, and results were shown to be consistent across age groups, risk factors and previous flu vaccination status, with mRNA-1010 demonstrating an rVE of 27.4% in participants aged 65 years and older.
Seasonal flu is an acute respiratory infection caused by influenza viruses, which circulate in all parts of the world. Although most people can recover within a week without requiring medical attention, there is a risk of severe illness among certain groups, including young children, older adults and those with serious medical conditions.
According to the Centers for Disease Control and Prevention, seasonal flu-related hospitalisations and outpatient visits reached a 15-year high during the 2024-2025 season, with more than 600,000 people in the US hospitalised due to flu-related illness last year.
“[These] strong phase 3 efficacy results are a significant milestone in our effort to reduce the burden of influenza in older adults,” said Moderna’s chief executive officer, Stéphane Bancel. “The severity of this past flu season underscores the need for more effective vaccines.”
The World Health Organization cites vaccination as the current principal means of reducing the impact of flu on mortality and illness, but the ever-evolving nature of influenza viruses requires continuous global monitoring and frequent reformulation of vaccines.
“An mRNA-based flu vaccine has the potential advantage to more precisely match circulating strains, support rapid response in a future influenza pandemic, and pave the way for COVID-19 combination vaccines,” Bancel explained.
The company said it is planning to present full results from the trial at an upcoming medical conference and will “engage with regulators on filing submissions for mRNA-1010”.