New quadrivalent flu vaccine shows promise for kids under 3

NCT ID NCT05779020

First seen Jun 25, 2026 · Last updated Jun 26, 2026 · Updated 1 time

Summary

This completed Phase 3 trial tested a quadrivalent (four-strain) influenza vaccine from Instituto Butantan in over 1,300 healthy infants and children aged 6 to 35 months. The study compared the immune response and safety of two doses (0.25ml and 0.50ml) against standard trivalent (three-strain) flu vaccines. The goal was to see if the quadrivalent vaccine provides better protection against both B strains of the flu virus.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance

Quadrivalent influenza vaccine (split virion, inactivated)

What this could lead to

If successful, this vaccine could provide broader protection against four flu strains for young children, reducing flu-related illness and hospitalizations.

What could go wrong

This is a completed Phase 3 trial, but results are not yet published. The vaccine may not show significantly better protection than existing trivalent vaccines, and side effects like fever or injection-site reactions are possible.

Disclaimer Read more

This is a summary of the original study . Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.

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Conditions

The condition(s) this trial relates to.

influenza

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Locations

  • A2Z Clinical Centro Avançado de Pesquisa Clínica Ltda.(Site 001)

    Valinhos, São Paulo, 13271-130, Brazil

  • CPMC Pesquisa Clínica - Clinica De Alergia Martti Antila Sorocaba

    Sorocaba, São Paulo, 18040-425, Brazil

  • CPQuali Pesquisa Clínica Ltda (Site 002)

    São Paulo, 01228-000, Brazil

  • Centro Oncológico de Roraima - CECOR (Site BVB-01)

    Boa Vista, Roraima, 69304-015, Brazil

  • Centro de Pesquisa Clínica S (Site RAO03)

    Serrana, São Paulo, Brazil

  • Centro de Pesquisa Clínica do Instituto da Criança - Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (Site SAO08)

    São Paulo, 05403-000, Brazil

  • Centro de Pesquisas Clínicas da Universidade Federal de Sergipe (Site AJU01)

    Laranjeiras, Sergipe, 49170-000, Brazil

  • Hospital das Clínicas da Faculdade de Medicina Ribeirão Preto - USP (Site RAO 04)

    Ribeirão Preto, São Paulo, 14051-140, Brazil

  • Instituto Auto Imune de Pesquisa e Educação Continuada - Real Hospital Português de Beneficência em Pernambuco (Site REC01)

    Recife, Pernambuco, Brazil

  • Instituto de Pesquisa PENSI (Site SAO09)

    São Paulo, 01228-200, Brazil