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High-Dose Quadrivalent Influenza Vaccine

Tor Biering-Sørensen · FDA-approved active Small molecule

A high-dose inactivated influenza vaccine that stimulates a stronger immune response by delivering four times the standard antigen dose to enhance antibody production and cellular immunity against four influenza virus strains.

A high-dose inactivated influenza vaccine that stimulates a stronger immune response by delivering four times the standard antigen dose to enhance antibody production and cellular immunity against four influenza virus strains. Used for Influenza prevention in adults aged 65 years and older, Influenza prevention in immunocompromised adults.

At a glance

Generic nameHigh-Dose Quadrivalent Influenza Vaccine
Also known asQIV-HD, Efluelda®, Fluzone® High Dose, Efluelda™
SponsorTor Biering-Sørensen
Drug classInactivated influenza vaccine
ModalitySmall molecule
Therapeutic areaImmunology / Infectious Disease
PhaseFDA-approved

Mechanism of action

High-dose quadrivalent influenza vaccine contains increased quantities of hemagglutinin antigens from four influenza virus strains (two A subtypes and two B lineages) compared to standard-dose formulations. The higher antigen load triggers more robust innate and adaptive immune responses, resulting in higher antibody titers and improved protection, particularly in older adults and immunocompromised populations with diminished vaccine responsiveness.

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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