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FLUAD Quadrivalent

Centers for Disease Control and Prevention · FDA-approved active Biologic

FLUAD Quadrivalent is an inactivated influenza vaccine that stimulates the immune system to produce antibodies against four strains of influenza virus.

FLUAD Quadrivalent is an inactivated influenza vaccine that stimulates the immune system to produce antibodies against four strains of influenza virus. Used for Seasonal influenza prevention in adults and children ≥6 months of age.

At a glance

Generic nameFLUAD Quadrivalent
Also known asInfluenza Vaccine, Adjuvanted (Quadrivalent), aIIV4
SponsorCenters for Disease Control and Prevention
Drug classInactivated quadrivalent influenza vaccine
ModalityBiologic
Therapeutic areaImmunology / Infectious Disease
PhaseFDA-approved

Mechanism of action

The vaccine contains inactivated (killed) influenza virus particles representing four circulating influenza strains (two A subtypes and two B lineages). When administered, it triggers both humoral and cellular immune responses, leading to the production of protective antibodies and memory immune cells that recognize and neutralize the corresponding live influenza viruses upon natural exposure.

Approved indications

Common side effects

Key clinical trials

Primary sources

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