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FLU HD vaccine

GlaxoSmithKline · Phase 3 active Biologic ✓ Verified May 2026

FLU HD vaccine is a Inactivated influenza vaccine Biologic drug developed by GlaxoSmithKline. It is currently in Phase 3 development for Prevention of influenza in adults aged 65 years and older, Prevention of influenza in adults aged 18 years and older (Phase 3 evaluation).

FLU HD vaccine stimulates a stronger immune response against influenza virus by delivering a higher antigen dose compared to standard-dose flu vaccines.

The FLU HD vaccine is a high-dose, quadrivalent, inactivated influenza vaccine that induces an immune response. It is used to prevent influenza in individuals, with its mechanism of action classified as a biological vaccine.

Likelihood of approval
62.3% vs 58.3% industry baseline
If approved by FDA: likely 2028–2030
Steps remaining: NDA/BLA submission
Confidence: High
Why this estimate
  • Baseline phase 3 → approval rate +58.3pp
    Industry-wide phase 3 drugs reach approval ~58.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).
  • Immunology slight uplift +1.0pp
    Mature endpoint landscape (ACR, DAS28, PASI) makes immunology approvals slightly more predictable.
  • Big-pharma sponsor +3.0pp
    GlaxoSmithKline is a top-20 pharma sponsor — historical approval rates run ~3pp above average due to scale, regulatory experience, and trial-design quality.
Predicted approval windows by jurisdiction (conditional on FDA approval)
Regulator Country Likely year Lag vs FDA
FDA US 2028–2030
EMA EU 2029–2031 +0.7 yr
MHRA GB 2029–2031 +0.7 yr
Health Canada CA 2029–2032 +0.9 yr
TGA AU 2029–2032 +1.2 yr
PMDA JP 2029–2032 +1.5 yr
NMPA CN 2030–2033 +2.3 yr
MFDS KR 2029–2032 +1.4 yr
CDSCO IN 2029–2033 +1.8 yr
ANVISA BR 2030–2033 +2.3 yr

Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).

Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.

At a glance

Generic nameFLU HD vaccine
SponsorGlaxoSmithKline
Drug classInactivated influenza vaccine
ModalityBiologic
Therapeutic areaImmunology / Infectious Disease
PhasePhase 3

Mechanism of action

FLU HD is an inactivated influenza vaccine formulated with four times the standard antigen content per strain, designed to elicit a more robust humoral and cellular immune response, particularly in older adults who may have diminished immune responsiveness. The higher antigen dose aims to improve vaccine efficacy and reduce influenza-related morbidity and mortality in elderly populations.

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

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

Frequently asked questions about FLU HD vaccine

What is FLU HD vaccine?

FLU HD vaccine is a Inactivated influenza vaccine drug developed by GlaxoSmithKline, indicated for Prevention of influenza in adults aged 65 years and older, Prevention of influenza in adults aged 18 years and older (Phase 3 evaluation).

How does FLU HD vaccine work?

FLU HD vaccine stimulates a stronger immune response against influenza virus by delivering a higher antigen dose compared to standard-dose flu vaccines.

What is FLU HD vaccine used for?

FLU HD vaccine is indicated for Prevention of influenza in adults aged 65 years and older, Prevention of influenza in adults aged 18 years and older (Phase 3 evaluation).

Who makes FLU HD vaccine?

FLU HD vaccine is developed by GlaxoSmithKline (see full GlaxoSmithKline pipeline at /company/gsk).

What drug class is FLU HD vaccine in?

FLU HD vaccine belongs to the Inactivated influenza vaccine class. See all Inactivated influenza vaccine drugs at /class/inactivated-influenza-vaccine.

What development phase is FLU HD vaccine in?

FLU HD vaccine is in Phase 3.

What are the side effects of FLU HD vaccine?

Common side effects of FLU HD vaccine include Injection site soreness, Myalgia, Headache, Fatigue, Fever.

Related

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing