THURSDAY, May 7, 2026 (HealthDay News) -- For adults aged 50 years or older, an investigational messenger RNA (mRNA)-based vaccine (mRNA-1010) is superior to standard-dose licensed vaccines for preventing influenza-like illness, according to a study published in the May 7 issue of the New England Journal of Medicine.
Isabel Leroux‑Roels, M.D., from Ghent University and Ghent University Hospital in Belgium, and colleagues conducted a phase 3, double-blind, active-controlled trial involving adults aged 50 years or older who were randomly assigned to receive trivalent mRNA-1010 (37.5 μg, which includes 12.5 μg of each World Health Organization recommendation influenza strain) or a licensed standard-dose comparator. Relative vaccine efficacy against reverse-transcriptase-polymerase-chain-reaction (RT-PCR)-confirmed, protocol-defined influenza-like illness caused by influenza A or B, from at least 14 days after vaccination through the end of the influenza season, was examined as the primary efficacy end point.
Overall, 20,350 participants received mRNA-1010 and 20,353 received the standard-dose comparator. The researchers found that 2.0 and 2.8 percent of the recipients of mRNA-1010 and the standard-dose comparator, respectively, had RT-PCR-confirmed, protocol-defined influenza-like illness, corresponding to a relative vaccine efficacy of 26.6 percent and meeting the criteria for noninferiority, superiority, and higher-level superiority. Solicited adverse reactions occurred more often with mRNA-1010 than the standard-dose comparator; they were mainly mild-to-moderate and transient. Overall, 2.2 and 1.9 percent of recipients of mRNA-1010 and the standard-dose comparator, respectively, had serious adverse events.
"These findings support the role of mRNA-1010 in improving influenza prevention," the authors write.
The study was funded by Blackstone Life Sciences and Moderna, the manufacturer of mRNA-1010.
