Vaccine candidate demonstrates 26.6% higher relative efficacy in adults 50 and older, with strong protection across flu strains.
Moderna, Inc announced positive phase 3 results for its seasonal influenza vaccine candidate, mRNA-1010, demonstrating a 26.6% higher relative vaccine efficacy (rVE) compared to a licensed standard-dose flu vaccine in adults aged 50 years and older (95% CI: 16.7%, 35.4%). The pivotal study enrolled 40,805 adults across 11 countries and showed strong efficacy against each influenza strain included in the vaccine: A/H1N1 (rVE=29.6%), A/H3N2 (rVE=22.2%), and B/Victoria lineages (rVE=29.1%).1
Participants aged 65 and older experienced a 27.4% rVE. The randomized, observer-blind, active-controlled P304 study (NCT06602024) followed participants for a median of six months, comparing a single dose of mRNA-1010 to a standard-dose licensed comparator. Safety and tolerability were consistent with previous phase 3 data,2 with mostly mild solicited adverse reactions such as injection site pain, fatigue, headache, and myalgia. No significant differences were observed in serious adverse events or adverse events of special interest.1
mRNA-1010 achieved 26.6% greater relative vaccine efficacy compared to a licensed standard-dose flu vaccine in adults aged 50+.
The vaccine showed strong strain-specific efficacy, including 29.6% against A/H1N1 and 27.4% efficacy in those 65 and older.
Safety profile was consistent with previous studies, with mostly mild adverse reactions and no significant safety concerns.
“This milestone highlights the potential of mRNA technology to improve influenza vaccination, especially for older adults who are at higher risk,” said Stéphane Bancel, Moderna’s CEO.1
He emphasized the advantages of mRNA vaccines, including better strain matching, rapid pandemic response capability, and potential for future combination vaccines with COVID-19.1 mRNA-1010 had previously demonstrated superior immune responses compared to high-dose and standard-dose licensed vaccines in earlier phase 3 studies.2
According to the CDC, the 2024-2025 flu season saw a 15-year high in flu-related hospitalizations and outpatient visits, with over 600,000 hospitalizations in the US alone. Moderna plans to present these results at an upcoming medical conference and pursue regulatory filings for mRNA-1010.3
