Moderna mFLUSIVA FDA Approval marks a significant milestone in messenger RNA (mRNA) medicine as the U.S. Food and Drug Administration officially approves mFLUSIVA® (mRNA-1010), a new seasonal influenza vaccine for active immunization in adults 50 years of age and older. Announced on August 5, 2026, by Cambridge, Massachusetts-based Moderna, Inc. (NASDAQ: MRNA), the regulatory milestone follows unanimous recommendations supporting the vaccine from the FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC). The regulatory approval establishes mFLUSIVA as Moderna’s fifth commercial product approved globally and its fourth FDA-approved product in the United States, further validating the broad versatility and scientific potential of the company’s proprietary messenger RNA platform.
In an official corporate announcement, Stéphane Bancel, Chief Executive Officer of Moderna, emphasized the major public health implications of this regulatory decision. Bancel noted that seasonal influenza remains a significant public health challenge for older demographics and that mFLUSIVA provides an important new preventive immunization option for seniors across the United States. Moderna expects to begin supplying mFLUSIVA to select retail pharmacy locations across the country in the coming weeks ahead of the 2026-2027 respiratory virus season. The new influenza vaccine will be commercialized alongside Moderna’s existing U.S. respiratory portfolio, which includes Spikevax® (COVID-19 Vaccine, mRNA), mRESVIA® (Respiratory Syncytial Virus Vaccine), and mNEXSPIKE® (COVID-19 Vaccine, mRNA).
Clinical Efficacy and Phase 3 Trial Parameters: Moderna mFLUSIVA FDA Approval
The FDA granted full regulatory approval for adults aged 50 through 64 years based on clinical results from a randomized, observer-blind, active-controlled Phase 3 clinical trial (ClinicalTrials.gov Identifier: NCT06602024). This multi-country clinical study enrolled 40,805 adult participants aged 50 years and older across 11 countries. Primary clinical objectives evaluated the safety, reactogenicity, and relative vaccine efficacy (rVE) of mFLUSIVA compared against a standard-dose (SD) active comparator vaccine against reverse transcription polymerase chain reaction (RT-PCR)-confirmed protocol-defined influenza-like illness caused by any influenza A or influenza B strains.
For adults 65 years of age and older, the FDA granted accelerated approval based on immunogenicity outcomes from a randomized, observer-blind, active-controlled clinical trial (ClinicalTrials.gov Identifier: NCT05827978). This study enrolled 2,992 adults aged 65 years and older in the United States to evaluate the immunogenicity of mFLUSIVA compared against a high-dose (HD) inactivated influenza vaccine comparator. Efficacy in adults aged 65 and older is additionally supported by descriptive rVE analyses from the 40,805-participant Phase 3 study (NCT06602024). Under accelerated approval guidelines, confirmation of clinical benefit in this senior population will be formally evaluated in a postmarketing clinical trial.
International expansion of mRNA-1010 is progressing simultaneously. Regulatory applications for the seasonal flu vaccine have been accepted for formal regulatory review by health authorities in the European Union, Canada, and Australia, with additional global regulatory filings planned throughout 2026.
Comprehensive Trial Data and Clinical Specifications
| Operational & Trial Parameter | Phase 3 Clinical Study (NCT06602024) | Phase 3 Clinical Study (NCT05827978) |
| Target Indication & Age Group | Active influenza immunization in adults 50–64 years | Active influenza immunization in adults 65+ years |
| Enrollment & Geography | 40,805 participants across 11 countries | 2,992 participants in the United States |
| Regulatory Pathway | Standard U.S. FDA Approval | Accelerated FDA Approval |
| Active Study Comparator | Standard-Dose (SD) Active Comparator Vaccine | High-Dose (HD) Inactivated Influenza Vaccine |
| Primary Study Endpoint | Relative Vaccine Efficacy (rVE) & Safety | Immunogenicity & Comparative Antibody Response |
| Clinical Requirements | Met primary safety & rVE endpoints | Confirmatory postmarketing trial required |
Safety Profile, Precautions, and Adverse Reactions
Across Phase 3 clinical evaluations, mFLUSIVA demonstrated an acceptable safety profile with no new safety concerns identified, remaining consistent with previously reported clinical studies of the mRNA-1010 candidate. Local injection site side effects reported in clinical trials included pain, tenderness, redness, hardness (swelling), and axillary lymph node swelling in the same arm as the injection. Systemic adverse reactions reported by trial participants included fatigue, headache, myalgia (muscle pain), arthralgia (joint pain), chills, nausea, vomiting, and fever. Rare severe allergic reactions may occur within minutes to one hour following administration.
