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Fluzone Quadrivalent Influenza Vaccine

Sanofi Pasteur, a Sanofi Company · FDA-approved active Biologic

Fluzone Quadrivalent stimulates the immune system to produce antibodies against four strains of influenza virus, providing protection against seasonal flu infection.

Fluzone Quadrivalent stimulates the immune system to produce antibodies against four strains of influenza virus, providing protection against seasonal flu infection. Used for Seasonal influenza prevention in persons 6 months of age and older.

At a glance

Generic nameFluzone Quadrivalent Influenza Vaccine
Also known asFluzone® Quadrivalent Influenza Vaccine
SponsorSanofi Pasteur, a Sanofi Company
Drug classinactivated influenza vaccine
ModalityBiologic
Therapeutic areaImmunology
PhaseFDA-approved

Mechanism of action

The vaccine contains inactivated (killed) influenza virus particles representing four circulating strains (two A subtypes and two B lineages). When administered, it triggers both humoral and cellular immune responses, leading to the production of strain-specific antibodies and memory B cells. This immune priming allows the body to rapidly recognize and neutralize the corresponding live virus if exposure occurs, reducing infection risk and disease severity.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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