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A Study of OVX836 Influenza Vaccine Given as Booster or Primary Vaccination in Healthy Adults Who Previously Received OVX836, Influenza Vaccine, or Placebo

Verified siteInvestigationalNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial focuses on testing a new influenza vaccine called OVX836. The vaccine is given as a single intramuscular injection and is being studied at two different dose levels. The purpose is to evaluate how well the vaccine works and how safe it is when given to healthy adults who have previously received either OVX836, Influvac Tetra, or placebo in earlier studies.

The study involves comparing the effects of the vaccine when used as either a booster shot in people who have already received OVX836 before, or as a first-time vaccination in those who haven't. Participants will receive a single injection of either 180 or 480 micrograms of the vaccine solution. The study is designed as a double-blind trial, which means neither the participants nor the researchers directly involved in giving the vaccine know who receives which dose.

During the study, researchers will monitor participants' immune system responses to the vaccine and track any side effects that may occur. This includes checking for both expected reactions at the injection site and throughout the body, as well as any unexpected health issues. The study will also track whether participants develop any respiratory infections, including influenza, during the study period.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial vaccination

    You will receive a single intramuscular injection of the study vaccine. The dose will be either 180µg or 480µg of OVX836 influenza vaccine.

    The specific dose will be assigned randomly, and neither you nor the medical staff will know which dose you receive (this is called double-blind).

  2. Step 2

    First week monitoring

    For 7 days after vaccination, you will need to record any reactions at the injection site (such as pain or redness) and any general symptoms in an electronic diary.

    The medical team will monitor your health status during this period.

  3. Step 3

    Day 8 assessment

    You will need to visit the study center for a blood sample collection.

    The blood sample will be used to measure your body's immune response to the vaccine.

  4. Step 4

    29-day follow-up period

    You will need to report any unexpected health issues for 29 days after vaccination.

    On day 29, you will visit the study center for another blood sample collection to measure your immune response.

  5. Step 5

    Extended monitoring

    The study will continue to monitor your health status until the study ends (estimated June 2025).

    You will need to report any flu-like symptoms or respiratory infections that occur during this period.

Who can join the trial?

9 criteria

  • You must voluntarily agree and sign an informed consent form to participate in the study
  • You must be considered healthy based on your medical history and examination
  • You must meet specific reproductive requirements for both male and female participants
  • You must have previously participated in either:
    • The OVX836-002 study and received either OVX836 180µg or Influvac Tetra®, or
    • The OVX836-003 study
    • Your age must be between 20 and 64 years old
    • You must be willing and able to:
      • Commit to participating for the entire study duration
      • Follow all study procedures carefully
      • You must be able to use and complete an electronic diary (eDiary)

Who cannot join the trial?

12 criteria

  • History of severe allergic reactions or anaphylaxis to any vaccine components
  • Pregnancy or breastfeeding women
  • Participation in another clinical trial within the past 3 months
  • Current acute illness (temporary illness like cold or fever) or infection
  • History of autoimmune diseases (conditions where the immune system attacks healthy body tissues)
  • Immunodeficiency (weakened immune system) or use of medications that suppress the immune system
  • Receipt of any influenza vaccine within the past 6 months
  • History of Guillain-Barré syndrome (a rare disorder where the immune system attacks the nerves)
  • Any chronic medical condition that is not well controlled
  • Current use of blood thinners or medications that affect blood clotting
  • Bleeding disorders or conditions that make it difficult for blood to clot
  • History of serious adverse reactions to previous vaccines
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Investigated drugs

OVX836 is an investigational influenza vaccine being tested to protect against flu. It's a new type of flu vaccine that is given as an injection into the muscle. The vaccine aims to provide protection against influenza viruses. Influvac Tetra is an established seasonal flu vaccine that helps protect against four different strains of influenza virus. It is given as an injection into the muscle and is commonly used to prevent flu infections. Note: The trial includes different doses of OVX836, but these are variations of the same vaccine rather than different medications.

What is already known about the treatment

  • OVX836

    An investigational influenza vaccine administered through intramuscular injection, currently being studied in Phase 2a clinical trials. This vaccine is being evaluated at two different dose levels (180µg and 480µg) as both a primary vaccination and a booster shot for healthy adults. The vaccine represents a novel approach to influenza prevention, with clinical studies focusing on its immunogenicity and safety profile when compared to standard influenza vaccines like Influvac Tetra®. The primary purpose of this medication is to provide protection against influenza virus infections, with researchers particularly interested in its effectiveness as a booster dose for previously vaccinated individuals.

  • Influvac Tetra®

    A quadrivalent influenza vaccine administered via intramuscular injection, containing inactivated surface antigens from four different influenza virus strains. This established vaccine is widely used in clinical practice as a seasonal influenza preventive medication, providing protection against two influenza A virus strains and two influenza B virus strains. The vaccine works by stimulating the immune system to produce antibodies against the specific influenza virus strains included in its formulation, offering protection throughout the influenza season.

Investigated diseases

Influenza - A highly contagious viral respiratory infection that affects the nose, throat, and sometimes the lungs. The virus spreads through tiny droplets when infected people cough, sneeze, or talk. Symptoms typically appear suddenly and include fever, chills, muscle aches, fatigue, headache, dry cough, and runny or stuffy nose. The illness usually develops within 1-4 days after exposure to the virus. The infection causes inflammation of the respiratory tract and can vary in severity from mild to severe.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-516267-83-00Protocol codeOVX836-007Estimated enrolment117 patientsSponsorOSIVAX Belgique

sourced from the EU Clinical Trials Register and site verification

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