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Study on the Best Time for Influenza Vaccine Administration in Adults Aged 60-85 Using Influenza Vaccine and Drug Combination

Verified siteRegistered drugNo 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 is focused on studying the effects of the time of day when the influenza vaccine is given to adults aged 60 to 85 years. The study will use two different vaccines: Vaxigrip Tetra and Influvac Tetra, both of which are designed to protect against the flu. These vaccines are given as an injection into the muscle and contain inactivated parts of the flu virus, which means they cannot cause the flu but help the body build protection against it.

The main goal of the study is to see how the timing of the vaccine affects the body's immune response, specifically the level of antibodies, which are proteins that help fight infections. Participants will receive the vaccine at different times of the day, and their antibody levels will be measured 28 days after vaccination. The study will also look at other factors, such as the participants' natural sleep-wake patterns, known as chronotype, and the occurrence of flu-like symptoms over a six-month period.

Participants will be randomly assigned a time to receive their vaccine and will be monitored for changes in their immune response. The study aims to provide insights into whether the time of day can influence the effectiveness of the flu vaccine, potentially leading to improved vaccination strategies for older adults. The study is expected to conclude by May 2025.

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

    Joining the study

    Upon joining the study, participants are required to provide written informed consent, confirming their understanding and agreement to participate in the trial.

    Participants must be aged between 60 and 85 years and be willing to attend the vaccination location at a randomly assigned time slot.

  2. Step 2

    Vaccination

    Participants will receive an influenza vaccine. The vaccine is administered as an injection into the muscle, known as an intramuscular injection.

    The vaccine used is a quadrivalent influenza vaccine, which means it is designed to protect against four different strains of the influenza virus.

  3. Step 3

    Post-vaccination monitoring

    After receiving the vaccine, participants will be monitored for any immediate reactions to the injection.

    Participants will be asked to report any symptoms or side effects they experience following the vaccination.

  4. Step 4

    Follow-up period

    Participants will be required to attend a follow-up appointment approximately 28 days after vaccination. This is to measure the increase in specific antibodies in the blood, which are proteins that help fight infections.

    During the follow-up period, participants will also be asked to complete a questionnaire about their sleep patterns, known as the micro-Munich Chronotype Questionnaire.

  5. Step 5

    Self-monitoring

    Participants will be provided with rapid influenza diagnostic self-tests to monitor for any signs of influenza infection during the six-month follow-up period.

    Participants are encouraged to report any symptoms that resemble influenza-like illness during this time.

Who can join the trial?

4 criteria

  • Aged 60-85 years at the time of inclusion.
  • Willing and able to come to the vaccination location at a randomly assigned timeslot.
  • Available for the follow-up period of 6 months.
  • Have provided written informed consent (this means you understand the study and agree to participate).

Who cannot join the trial?

9 criteria

  • People who are not between the ages of 60 and 85 years old.
  • Individuals who are not available for follow-up 28 days after vaccination.
  • Anyone who has a known allergy to the influenza vaccine or any of its components.
  • Individuals who have received another vaccine within 4 weeks prior to the study.
  • People who have a history of severe allergic reactions, also known as anaphylaxis, to any substance.
  • Individuals with a weakened immune system, which means their body has a harder time fighting infections.
  • Anyone currently participating in another clinical trial.
  • Individuals who have had a recent illness or infection that could interfere with the study results.
  • People who are unable to provide informed consent, which means they cannot fully understand the study and agree to participate.
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Investigated drugs

Influenza Vaccine The influenza vaccine is a shot given to help protect against the flu. It works by helping your body build up defenses, called antibodies, against the flu virus. This vaccine is especially important for older adults, as they are more at risk of getting very sick from the flu. In this trial, the researchers are looking at whether the time of day you get the vaccine affects how well it works in people aged 60 to 85.

What is already known about the treatment

Influenza Vaccine – The influenza vaccine is administered as an injection, typically into the muscle of the upper arm. It is currently a well-established preventive measure in medicine, widely documented in medical literature for its role in reducing the incidence of influenza. The main therapeutic indication for the influenza vaccine is to prevent influenza infection, particularly in older adults and other high-risk groups. At the molecular level, the vaccine works by stimulating the body's immune system to produce antibodies that recognize and fight the influenza virus. It is classified pharmacologically as a vaccine, which is a type of biological preparation that provides active acquired immunity to a particular infectious disease.

Investigated diseases

Influenza – Influenza, commonly known as the flu, is a contagious respiratory illness caused by influenza viruses. It primarily affects the nose, throat, and sometimes the lungs. The disease typically begins suddenly and is characterized by symptoms such as fever, cough, sore throat, muscle aches, fatigue, and headaches. As the illness progresses, symptoms can become more severe, leading to complications like pneumonia, especially in older adults and those with weakened immune systems. The flu spreads through droplets when an infected person coughs, sneezes, or talks, and it can also be contracted by touching surfaces contaminated with the virus. Recovery usually occurs within a few days to less than two weeks, although some individuals may experience lingering symptoms.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-513558-30-00Protocol codeIIV-654Estimated enrolment440 patientsSponsorRijksinstituut voor Volksgezondheid en Milieu (RIVM)

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