Moderna mFlusiva Receives FDA Approval for Adults Aged 50 and Older Patients

In August 2025, Moderna got FDA approval for mFlusiva as the first mRNA-based influenza vaccine for adults aged 50 years and older. The vaccine received accelerated approval based on immune responses for persons aged 65 years and older, necessitating a future trial to confirm clinical benefits upon verification and description of clinical benefit in a confirmatory postmarketing trial.

What You Need to Know About the New mRNA Flu Shot

Moderna’s mFlusiva is a vaccine for preventing influenza caused by specific virus subtypes A and B. Each 0.38mL dose contains mRNA encoding hemagglutinin proteins from three strains: A/Missouri/11/2025 (H1N1), A/Michigan/105/2025 (H3N2), and B/Pennsylvania/19/2025. These strains align with FDA recommendations for the 2026-2027 season.

Approval was supported by a phase 3 trial (NCT06602024) comparing mFlusiva with Fluarix® in individuals aged 50 and older. Among participants, RT-PCR-confirmed influenza-like illness (ILI) occurred in 2% of mFlusiva recipients and 2.8% of the comparator group, resulting in a relative vaccine efficacy (rVE) of 26.6%, meeting the superiority criterion. For those aged 65 and older, the rVE was 27.4%.

Another phase 3 study (NCT05827978) involving individuals aged 65+ assessed immunogenicity and safety, finding that the mRNA vaccine met all coprimary endpoints. Most common adverse reactions for participants aged 50-64 included injection site pain (68.7%) and fatigue (48.1%), while for those 65 and older, pain (62.9%) and fatigue (42.1%) were also prevalent.

Ronald G. Nahass, MD, MHCM, FIDSA, President of the Infectious Diseases Society of America, emphasized that the approval highlights the tremendous potential of mRNA vaccine technology. mFlusiva is supplied as a single-dose prefilled syringe for intramuscular injection. The approval underscores the potential of mRNA technology in vaccine development. The vaccine is expected to be available soon.

Impact on the Healthcare Industry

This approval positively impacts the healthcare industry by replacing slow and traditional egg-based manufacturing with a nimble genetic platform, enhancing protection for older populations who often suffer lower efficacy from legacy flu shots.

This approval may help to accelerate higher efficacy by providing about 26% to 27% better relative efficacy against confirmed flu illness compared to standard-dose licensed options for streamlined future strain updates, and it mitigates severe hospitalizations in high-risk older adults. mRNA flu vaccines offer major advantages over traditional egg-based shots by cutting production time from six months to two or three months. This speed reduces strain mismatch risks and helps deliver better-matching formulas through targeted lipid nanoparticle delivery.

Despite these benefits, several challenges remain for public health adoption, including slightly higher short-term side effects like fatigue and muscle pain, complex cold-chain storage demands, and logistical hurdles. Because clinics pre-order traditional supplies months ahead, full market adoption is gradual.

Impact on the mRNA Vaccines and Therapeutics Industry

The global mRNA vaccines and therapeutics market size was accounted for USD 116.88 billion in 2025 and is expected to reach around USD 297.84 billion by 2035, expanding at a solid CAGR of 9.81% from 2026 to 2035.

According to Precedence Research, this approval marks a contributing transition for mRNA vaccines and therapeutics from pandemic emergency response into the routine, multibillion-dollar endemic.

This will definitely benefit industry by proving that platform tech can successfully branch into diverse and recurring seasonal indications. An mRNA flu vaccine for adults aged 50 and older achieved roughly 27% higher relative efficacy in Phase 3 trials over standard egg-based shots, protecting a vulnerable group with fast synthetic mRNA manufacturing and reducing strain mismatch challenges.

This tech bypasses physical reliance on chicken egg supplies and long lead times to lock in viral strains closer to immunization seasons, with diversifying portfolios into yearly revenues.  It is facing challenges such as regulatory friction, higher local side effects, and a demand for trials in adults over 65 and insurance coverage.

Impact on the Influenza Vaccine Industry

The global influenza vaccine market size is valued at USD 9.02 billion in 2025 and is predicted to increase from USD 9.73 billion in 2026 to approximately USD 19.19 billion by 2035, expanding at a CAGR of 7.84% from 2026 to 2035.

According to Precedence Research, it marks a positive impact on the industry by validating synthetic mRNA platforms beyond emergency pandemic use with higher relative efficacy than standard-dose egg-based shots and reducing production lead times from months down to weeks.

This validates the mRNA platform for non-COVID seasonal vaccines and thus sets a new efficacy benchmark for adults, accelerating immunogenicity approvals for adults and improving regulatory pathways for traditional manufacturers. By mitigating egg dependency and lowering strain-matching timelines, this synthetic approach enhances immunogenicity in aging populations by outpacing conventional vaccine technology.

About Moderna

Moderna, Inc. is a Cambridge, Massachusetts-based biotechnology company that leverages mRNA science to treat human biology like a programmable software platform. The company builds a profitable seasonal respiratory franchise, featuring Spikevax, mRESVIA, mFLUSIVA, and mCOMBRIAX, to finance a broad clinical pipeline such as personalized cancer vaccines, rare disease treatments, and defenses against latent pathogens like HIV and CMV. Its overall aim is to maximize human health by turning genetic code into transformative vaccines and medicines for infectious diseases, immuno-oncology, and rare genetic diseases.