Moderna's mRNA-1010 flu shot heads to FDA on a 26.6% efficacy edge over standard vaccines
The August 5 PDUFA date tests whether a Phase 3 win against licensed flu vaccines in adults 50 and older, published in NEJM, converts into the first mRNA seasonal flu approval.
Executive Summary
- Moderna's mRNA-1010 seasonal flu vaccine goes before the FDA on a pivotal trial that already cleared its efficacy bar against a licensed comparator vaccine, shifting the question from whether the shot works to whether the agency accepts the full package as filed.
- The completed Phase 3 study met its most stringent prespecified superiority threshold with efficacy that held up across strains, age bands, and risk groups, giving the filing a clinical result but leaving the trial's other co-primary safety endpoints without disclosed outcomes.
- No other program shares mRNA-1010's mRNA mechanism paired with a seasonal influenza indication, positioning this as the first test of whether that platform can displace egg- and cell-based flu vaccines rather than one entrant among many.
- An approval would hand Moderna a second commercial mRNA vaccine and open a path toward multi-region rollout already queued in Europe, Canada, and Australia; a rejection or restricted label would leave the platform's non-COVID commercial case unproven.
The decision ahead
Moderna has a Food and Drug Administration Prescription Drug User Fee Act (user-fee review) goal date of August 5, 2026 for mRNA-1010, its investigational seasonal influenza vaccine. The application rests on NCT06602024, a Phase 3 trial that enrolled 40,817 adults aged 50 and older and compared mRNA-1010 against a licensed standard-dose seasonal influenza vaccine, with Fluarix, Fluarix Tetra, Influsplit Tetra, and Alpharix Tetra named as comparators. The trial started September 16, 2024, reached a primary completion date of August 21, 2025, and was marked Completed. Regulatory filings have been accepted for review in the United States, European Union, Canada, and Australia, with additional country submissions planned in 2026. Moderna+1Moderna Announces New England Journal of Medicine Publication of Pivotal Phase 3 Clinical Safety and Efficacy Data for Its Investigational Seasonal Influenza Vaccine, mRNA-1010May 6, 2026A Study of mRNA-1010 Compared With a Licensed Influenza Vaccine in Adults ≥50 Years of AgeNCT06602024
Probability of SuccessBased on the AppliedXL Probability of Success model. For more information about the methodology, read the research here.
The result
Moderna reported that mRNA-1010 achieved the most stringent superiority criterion prespecified in the protocol, with a relative vaccine efficacy (rVE, the vaccine's effect relative to a licensed comparator rather than placebo) of 26.6% (95% CI 16.7%-35.4%) against the overall trial population. Efficacy held across the three included strains: 29.6% against A/H1N1, 22.2% against A/H3N2, and 29.1% against the B/Victoria lineage. In participants 65 and older, rVE was 27.4%, and Moderna said subgroup analyses across age groups, risk factors, and prior vaccination status confirmed a consistent point estimate. Stephane Bancel, Moderna's chief executive, said the New England Journal of Medicine publication "reflects the strength of the clinical evidence supporting our ongoing regulatory submissions". The trial's own registry record lists four co-primary endpoints spanning adverse-event categories and time to first confirmed influenza-like illness; the disclosed rVE result maps to the illness endpoint, while the trial's medically attended adverse event, discontinuation, and adverse-event-of-special-interest endpoints carry no disclosed outcome. Moderna+1Moderna Announces New England Journal of Medicine Publication of Pivotal Phase 3 Clinical Safety and Efficacy Data for Its Investigational Seasonal Influenza Vaccine, mRNA-1010May 6, 2026A Study of mRNA-1010 Compared With a Licensed Influenza Vaccine in Adults ≥50 Years of AgeNCT06602024
Trial course
The registry shows two primary completion date revisions and one enrollment change over the trial's life. The primary completion date moved from December 5, 2025 to June 5, 2026 in an April 2025 amendment, then the trial completed early, on August 21, 2025. Enrollment closed at 40,817, down from a prior count of 56,000 recorded before completion. That change reflects the trial's actual accrual at completion rather than a target cut announced during enrollment; the study reached Completed status cleanly in September 2025 with no gap in disclosure between that status change and the NEJM publication eight months later. NCT06602024+1A Study of mRNA-1010 Compared With a Licensed Influenza Vaccine in Adults ≥50 Years of AgeNCT06602024Moderna Announces New England Journal of Medicine Publication of Pivotal Phase 3 Clinical Safety and Efficacy Data for Its Investigational Seasonal Influenza Vaccine, mRNA-1010May 6, 2026
The competitive frame
No competitor shares mRNA-1010's messenger RNA mechanism combined with a seasonal influenza indication in active testing; the nearest programs sharing the modality are GlaxoSmithKline's GSK6498032A, an earlier-phase mRNA flu candidate, and Moderna's own mRNA-1273 and mRNA-1283 COVID-19 vaccines, which use the same platform against a different pathogen. Seasonal influenza vaccination today runs on egg- and cell-based platforms; an mRNA entrant with a superiority result against a licensed comparator, rather than a placebo, would be the first attempt to establish that the platform's efficacy advantage translates into a labeled seasonal product in this population.
This analysis was produced using AI-assisted reporting systems, AppliedXL data, and official public records. These systems undergo editorial review, quality checks, and regular audits by human experts. Errors may still occur, as with any automated system. Always consult the linked primary sources. Read our AI Editorial Policy.