Level 1 - Absolute Beginner
A group of experts voted yes on a new flu shot. The shot was made by a company called Moderna. All nine experts said yes.
This flu shot uses new technology called mRNA. This is the same technology used in some COVID vaccines. It may work better than old flu shots.
The new shot is for adults who are 50 years old or older. Doctors and the government still need to give final approval. It could be ready in the fall.
- flu
- a common illness caused by a virus that makes you feel sick, tired, and often gives you a fever
- vaccine
- a medicine given to protect you from getting sick from a specific disease
- approved
- officially accepted or allowed by a group or government
- mRNA
- a tiny set of instructions that tells your body how to fight a disease
- technology
- new tools or methods that help people do things in a better way
- experts
- people who know a lot about a specific topic
- vote
- to make a choice together as a group, saying yes or no
- fall
- the season between summer and winter, also called autumn
Level 2 - Elementary
A group of government health advisors voted 9 to 0 on June 23, 2026, to recommend a new kind of flu vaccine made by Moderna. The vaccine, called mRNA-1045, uses messenger RNA technology - the same approach that made COVID vaccines so effective. This was the first time an mRNA flu vaccine had reached this important stage in the approval process.
Traditional flu vaccines are made by growing the virus in eggs and then killing it. The mRNA approach works differently. Instead of using an inactive virus, it gives your body instructions to build a protein from the flu virus. Your immune system then learns to fight the real virus if you are ever infected.
The advisory committee said the vaccine appeared to be more effective than regular flu shots, particularly for older adults. The FDA does not have to follow the committee's recommendation, but it usually does. If approved, mRNA-1045 could be available for the fall flu season.
- advisory committee
- a group of experts who give official recommendations to a government body
- unanimous
- when everyone in a group agrees on the same decision
- messenger RNA
- molecules that carry genetic instructions from DNA to the part of a cell that makes proteins
- immune system
- the body's natural defense system that fights against infections and disease
- regulatory
- related to rules and processes used by governments to control industries
- approval
- official permission granted by a government authority to allow a product to be used
- effective
- working well and producing the desired result
- inactive virus
- a virus that has been killed so it cannot cause illness but can still train the immune system
Level 3 - Intermediate
The Vaccines and Related Biological Products Advisory Committee, known as VRBPAC, voted 9 to 0 on June 23, 2026, to recommend that the FDA approve Moderna's mRNA-1045 flu vaccine for adults aged 50 and over. The unanimous decision marked the furthest an mRNA-based influenza vaccine had advanced in the US regulatory process, and was widely interpreted as a major milestone for the technology's expansion beyond COVID-19.
Unlike conventional inactivated influenza vaccines, mRNA-1045 uses lipid nanoparticles to deliver messenger RNA sequences encoding the hemagglutinin antigens of the four strains in the seasonal flu formula. Clinical trial data presented to the committee showed a relative vaccine efficacy of approximately 78 percent against symptomatic influenza compared to 40 to 60 percent typically observed with traditional vaccines. The mRNA platform also allows faster antigen updates, meaning manufacturers can adjust the vaccine formula more quickly as flu strains evolve each year.
The FDA is not required to follow VRBPAC recommendations but does so in the vast majority of cases. Moderna has also submitted rolling review applications to the European Medicines Agency and the UK's Medicines and Healthcare products Regulatory Agency. If the FDA grants a Biologics License Application in the coming weeks, the vaccine could reach pharmacies in time for the autumn 2026 flu season, with Moderna projecting premium pricing of between 12 and 18 dollars above the cost of a standard flu shot.
- hemagglutinin
- a protein on the surface of influenza viruses that the immune system recognizes and targets
- lipid nanoparticle
- a tiny fat-based capsule used to deliver mRNA into cells without it being destroyed
- antigen
- a substance, often on the surface of a virus or bacterium, that triggers an immune response
- inactivated vaccine
- a vaccine made from a killed pathogen that cannot cause disease but trains the immune system
- vaccine efficacy
- a measure of how well a vaccine reduces the risk of disease in clinical trials
- rolling review
- a regulatory process where a medicine is reviewed as data becomes available, speeding up approval
- VRBPAC
- Vaccines and Related Biological Products Advisory Committee, the FDA body that evaluates new vaccines
- demographic
- a specific section of the population defined by age, gender, or other characteristics
Level 4 - Advanced
The Vaccines and Related Biological Products Advisory Committee rendered a unanimous 9-0 recommendation on June 23, 2026, endorsing FDA approval of Moderna's mRNA-1045 quadrivalent influenza vaccine for adults aged 50 years and older - the first mRNA-platform influenza vaccine to clear this regulatory threshold in the United States. The decision reflected an accumulation of phase 3 immunogenicity and efficacy data demonstrating that mRNA-1045 elicited hemagglutinin inhibition titers significantly exceeding those produced by licensed IIV4 comparators, with a relative vaccine efficacy of approximately 78 percent against laboratory-confirmed symptomatic influenza A and B in the primary immunobridging population.
The mechanism distinguishes mRNA-1045 fundamentally from egg-adapted inactivated vaccines. Lipid nanoparticle encapsulation delivers modified mRNA sequences encoding four full-length, membrane-anchored hemagglutinin antigens, which ribosomes translate into protein in situ. The resulting antigen display on transfected cells drives robust CD4+ T-helper and CD8+ cytotoxic T-lymphocyte responses in addition to conventional B-cell antibody generation - an immunological breadth that IIV4 formulations do not reliably induce. Committee members noted that this T-cell depth may provide durability advantages for immunosenescent adults in whom antibody responses to conventional vaccines wane more rapidly.
The commercial implications are substantial. Moderna has positioned mRNA-1045 at a projected premium of twelve to eighteen dollars per dose over the standard reimbursed IIV4 price, targeting an addressable market estimated at approximately 500 million doses globally per season. The company has filed rolling review dossiers with the European Medicines Agency and the UK Medicines and Healthcare products Regulatory Agency. If the FDA issues the Biologics License Application in the near term - analysts expect a decision by late July - supply-chain modeling suggests sufficient production capacity to meet high-demand demographics before the Northern Hemisphere flu season peaks, cementing mRNA technology's transition from pandemic emergency tool to routine annual public health instrument.
- Biologics License Application
- the formal submission to the FDA requesting authorization to market a biological product in the United States
- multivalent
- a vaccine designed to protect against multiple strains or variants of a pathogen simultaneously
- HAI titer
- hemagglutinin inhibition titer, a laboratory measurement of antibody levels that block flu virus attachment to cells
- IIV4
- Inactivated Influenza Vaccine Quadrivalent, the standard egg-grown killed flu shot protecting against four strains
- CD4+ T-cell
- a type of immune cell (T-helper cell) that coordinates the body's immune response against pathogens
- CD8+ cytotoxic T-lymphocyte