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Quadrivalent Recombinant Influenza Vaccine

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

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

This vaccine stimulates the immune system to produce antibodies against four strains of influenza virus, providing protection against seasonal flu infection. Used for Prevention of seasonal influenza in adults 18 years of age and older.

At a glance

Generic nameQuadrivalent Recombinant Influenza Vaccine
Also known asFlublok Quadrivalent®, Flublok Quadrivalent, RIV4
SponsorSanofi Pasteur, a Sanofi Company
Drug classvaccine
ModalityBiologic
Therapeutic areaImmunology
PhaseFDA-approved

Mechanism of action

The quadrivalent recombinant influenza vaccine contains recombinant hemagglutinin proteins from four influenza virus strains (two A strains and two B strains) produced using recombinant DNA technology in insect cells. Upon administration, these antigens trigger both humoral and cellular immune responses, leading to the production of strain-specific antibodies and T-cell immunity that protect against infection with matching influenza viruses.

Approved indications

Common side effects

Key clinical trials

Primary sources

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

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