mRNA Flu Vaccine Availability for 2026-2027 Season
Yes, an mRNA influenza vaccine is available this season—Moderna's mRNA-1010 has been FDA-approved and is included among the vaccine options for the 2025-26 influenza season in the United States.
Available Vaccine Formulations
The 2025-26 season offers multiple vaccine types, and the most recent ACIP guidelines 1 list the following formulations as available:
- Trivalent inactivated influenza vaccines (IIV3s)
- Trivalent recombinant influenza vaccine (RIV3)
- Trivalent live attenuated influenza vaccine (LAIV3)
- mRNA-1010 (Moderna's mRNA influenza vaccine)
Evidence Supporting mRNA-1010
Moderna's mRNA-1010 represents the most clinically advanced mRNA influenza platform and has demonstrated superior efficacy in phase III trials 2. In adults aged ≥50 years, the optimized formulation achieved 26.6% relative efficacy (95% CI: 16.7%, 35.4%) compared to standard-dose vaccines. The vaccine induces robust humoral and cell-mediated responses, particularly against influenza A strains, with enhanced Fc-mediated effector functions and strong T helper 1 engagement 2.
Safety Profile
The safety profile aligns with licensed COVID-19 mRNA vaccines 2:
- Reactogenicity is higher than conventional vaccines
- Adverse reactions are predominantly mild-to-moderate and transient
- No significant safety concerns identified in clinical trials
Important Caveats
Comparison to Enhanced Formulations
While mRNA-1010 shows superiority over standard-dose vaccines, whether it offers incremental benefits over enhanced formulations (high-dose, adjuvanted, or recombinant vaccines) remains to be established 2. This is particularly relevant for older adults (≥65 years), where enhanced formulations are preferred options in some countries.
Pfizer's Candidate Status
Pfizer's modified-nucleoside RNA (modRNA) candidate showed mixed results 2:
- 34.5% relative efficacy in adults 18-64 years
- Failed to demonstrate non-inferiority in adults ≥65 years (relative efficacy: -5.8%)
- Not yet FDA-approved for routine use
Practical Considerations
The transition to single-dose pre-filled syringes and expanded refrigerated stability data significantly mitigates cold-chain challenges historically associated with mRNA vaccines 2. However, real-world implementation challenges may affect broader global health impact.
Selection Guidance
Per ACIP recommendations 1:
- All persons should receive an age-appropriate influenza vaccine
- Children aged ≤18 years, pregnant women, and all adults should receive vaccines only in single-dose formulations free of thimerosal as a preservative
- Vaccination should ideally occur during September or October
The mRNA-1010 vaccine represents a valid and FDA-approved option for the current season, though individual patient factors and availability of enhanced formulations should guide final vaccine selection,