The novel flu vaccine formulated with messenger RNA (mRNA) technology has officially arrived at pharmacies across the United States. Moderna's mFlusiva is now available nationwide at CVS pharmacies, while Walgreens is gearing up to receive shipments imminently.
FDA Approval and Eligibility Criteria
On August 6, the Food and Drug Administration (FDA) gave the green light to mFlusiva for individuals aged 50 and above, paving the way for its availability ahead of the flu season.
So, who qualifies for the mFlusiva vaccination? According to the FDA's authorization, mFlusiva is intended strictly for adults aged 50 and over. The agency provided standard approval for those between 50 to 64 years and an accelerated approval for individuals 65 years or older, contingent on an additional clinical trial for this age bracket.
Individuals outside this age range can opt for other approved flu vaccines suitable for their demographic.
How mFlusiva Operates Differently from Traditional Vaccines
Unlike traditional flu vaccines—which typically use inactivated virus versions cultivated in eggs—mFlusiva utilizes a small piece of genetic code to train the immune system to recognize and combat the virus.
"Think of it as a temporary instruction for your immune system to alert your body’s natural defenses to identify the flu," explained Emlah Tubuo, an independent pharmacist based in Ohio, to NBC News.
The mRNA disintegrates once its job is done, leaving no residue in the body. Immunity develops approximately two weeks post-vaccination.
A notable advantage over conventional vaccines is the production speed: while traditional formulas take about six months to manufacture, mFlusiva can be produced in just two to three months. Dr. William Schaffner, an infectious disease specialist at Vanderbilt University Medical Center, noted that this shorter timeline allows for more accurate strain targeting, enhancing effectiveness.
Effectiveness and Safety of mRNA Flu Vaccine
A Phase 3 clinical trial, published in the New England Journal of Medicine in May, involved over 40,000 adults aged 50 and above across 11 countries, including the U.S. The findings indicated that mFlusiva was roughly 27% more effective than a standard-dose vaccine in preventing lab-confirmed flu cases.
The FDA reviewers did not identify significant safety concerns. While side effects—such as injection site pain, fatigue, and headaches—were more common than in the standard vaccine group, they remained mild to moderate.
Insurance Coverage for mFlusiva
According to NBC News, mFlusiva is entering pharmacies without formal endorsement from the Centers for Disease Control and Prevention (CDC) or its vaccine advisory committee, which usually precedes insurance companies covering vaccines at no cost.
A representative from AHIP, a health insurance trade association, mentioned the expectation that most private insurers will cover the vaccine.
Dorit Reiss, a vaccine policy expert at the University of California's School of Law, stated that Medicare is obliged to fully cover FDA-approved seasonal flu vaccines. However, the lack of a CDC recommendation leaves coverage this season uncertain.
The Centers for Medicare and Medicaid Services indicate that mFlusiva is priced around $171 per dose without insurance. Depending on the pharmacy, the cost might be as low as $154, as per GoodRx, a free digital platform for comparing prescription drug prices in the U.S.
Specifics and Regulatory Journey of mFlusiva
Brigid Groves from the American Pharmacists Association clarified that mFlusiva targets only the flu and is distinct from Moderna's combined flu-COVID-19 vaccine.
The trivalent vaccine protects against two influenza A strains and one influenza B strain, offering no defense against COVID-19.
While the combined flu-COVID vaccine received European Union approval in April, it has yet to gain authorization in the United States.
The regulatory path for mFlusiva was rocky; initially, the FDA refused to review Moderna's application in February, citing improper comparator use for those over 65. The agency reversed this decision days later, and in June, an independent vaccine advisory panel unanimously recommended approval.
The CDC advises getting vaccinated by the end of October. The 2025-2026 flu season was notably severe in the U.S., with preliminary CDC estimates pointing to approximately 390,000 hospitalizations and 24,000 flu-related deaths.
Key Questions About mFlusiva Vaccine
Who is eligible for the mFlusiva vaccine?
mFlusiva is approved for adults aged 50 and older. Standard approval is for those 50-64 years old, with accelerated approval for individuals 65 and above, contingent on further clinical trials.
Does mFlusiva protect against COVID-19?
No, mFlusiva is specifically designed to protect against influenza and does not offer protection against COVID-19. It targets two strains of influenza A and one strain of influenza B.
Will insurance cover the cost of mFlusiva?
While many private insurers are expected to cover the vaccine, the lack of a formal CDC recommendation leaves Medicare's coverage uncertain. Without insurance, the cost is approximately $171 per dose.