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Flublok™ Quadrivalent by Sanofi, Inc.

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

Flublok Quadrivalent is an inactivated influenza vaccine produced using recombinant DNA technology that stimulates the immune system to produce antibodies against four strains of influenza virus.

Flublok Quadrivalent is an inactivated influenza vaccine produced using recombinant DNA technology that stimulates the immune system to produce antibodies against four strains of influenza virus. Used for Seasonal influenza prevention in adults 18 years of age and older.

At a glance

Generic nameFlublok™ Quadrivalent by Sanofi, Inc.
SponsorCenters for Disease Control and Prevention
Drug classRecombinant inactivated influenza vaccine
TargetInfluenza hemagglutinin (HA) protein
ModalityBiologic
Therapeutic areaImmunology / Infectious Disease
PhaseFDA-approved

Mechanism of action

The vaccine contains recombinant hemagglutinin proteins from four influenza virus strains (two A strains and two B strains) manufactured in insect cells using baculovirus expression technology. These proteins are recognized by the immune system as foreign antigens, triggering both humoral and cellular immune responses that generate protective antibodies and memory immunity against the targeted influenza strains.

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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