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Study on the Safety and Immune Response of JNJ-78901563 and High-dose Influenza Vaccine in Preventing E. coli Infections in Adults Aged 65 and Older

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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 prevention of a disease caused by a type of bacteria known as Escherichia coli, specifically the kind that can cause serious infections outside the intestines. The study will also look at the effects of a high-dose flu vaccine. The trial involves two main treatments: a vaccine called ExPEC9V and a high-dose quadrivalent influenza vaccine, which is designed to protect against four different strains of the flu virus. The study will explore how these vaccines work when given together and separately in adults aged 65 years or older.

The purpose of the study is to evaluate the immune response, which is how the body defends itself against infections, to the flu vaccine when it is given with the ExPEC9V vaccine compared to when the flu vaccine is given alone. Participants will receive injections of these vaccines, and some may receive a placebo. The study will monitor the safety and any reactions to the vaccines, as well as how well the immune system responds to them.

Participants in the study will be monitored over a period of time to assess their immune response to the vaccines. This will involve checking the levels of antibodies, which are proteins the body makes to fight infections, in the blood. The study aims to provide valuable information on the effectiveness and safety of these vaccines in older adults, helping to improve prevention strategies for both Escherichia coli infections and influenza.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial vaccination

    Upon joining the study, you will receive your first set of vaccinations. This includes the administration of two vaccines: ExPEC9V and a high-dose quadrivalent influenza vaccine. Both vaccines are given as injections into the muscle, known as intramuscular injections.

    The high-dose quadrivalent influenza vaccine is designed to protect against four different strains of the flu virus. The ExPEC9V vaccine aims to prevent diseases caused by a specific type of bacteria called extraintestinal pathogenic Escherichia coli (ExPEC).

  2. Step 2

    Monitoring period

    After receiving the vaccines, you will enter a monitoring period. During this time, you will be asked to keep track of any symptoms or side effects you may experience. This is done using an electronic diary, which you will need to complete regularly.

    You will be required to report any changes in your health, especially those that occur within the first 29 days after vaccination. This helps in assessing the safety and effectiveness of the vaccines.

  3. Step 3

    Follow-up visit

    Approximately 29 days after your initial vaccination, you will have a follow-up visit. During this visit, blood samples may be taken to measure your body's immune response to the vaccines.

    The focus will be on checking the levels of antibodies, which are proteins your body makes to fight infections, against the flu strains and the ExPEC bacteria.

  4. Step 4

    Ongoing observation

    You will continue to be observed for any long-term effects or benefits of the vaccines. This period extends up to three months after your last dose of the study vaccine.

    During this time, it is important not to donate blood, as this could affect the study results.

Who can join the trial?

10 criteria

  • Must be 65 years of age or older on the day of signing the consent form.
  • Must be medically stable at the time of vaccination. This means your health condition should not require significant changes in treatment in the 6 weeks before joining the study, and you should not expect to be hospitalized for worsening of your condition during the study.
  • Can be male or female.
  • If female, must be postmenopausal (no menstrual periods for 12 months without another medical reason) and not planning to become pregnant. Women who are surgically unable to have children are also eligible.
  • Must sign a consent form indicating understanding of the study's purpose, procedures, and potential risks and benefits, and willingness to participate.
  • Must be willing and able to follow the lifestyle restrictions specified in the study protocol.
  • Must agree not to donate blood from the time of vaccination until 3 months after receiving the last dose of the study vaccine.
  • Must be willing to provide identification, have a way to be contacted, and be able to contact the study investigator during the study.
  • Must be able to read, understand, and complete an electronic diary.
  • Must be able to work with smartphones, tablets, or computers.

Who cannot join the trial?

10 criteria

  • Patients who are not within the specified age range for the study.
  • Patients who have a known allergy to any component of the vaccines being tested.
  • Patients who have had a severe allergic reaction to any vaccine in the past.
  • Patients with a weakened immune system, which means their body has a reduced ability to fight infections.
  • Patients who are currently receiving treatment that affects the immune system, such as chemotherapy.
  • Patients with a history of certain neurological disorders, which are diseases of the brain and nerves.
  • Patients who are pregnant or planning to become pregnant during the study period.
  • Patients who have received another vaccine within a certain time frame before the study starts.
  • Patients who are participating in another clinical trial at the same time.
  • Patients with any other condition that the study doctors believe would make it unsafe for them to participate.
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Investigated drugs

  • ExPEC9V

    is a vaccine designed to protect against infections caused by a type of bacteria known as extraintestinal pathogenic Escherichia coli (ExPEC). These bacteria can cause serious infections, especially in older adults. The vaccine works by helping the body's immune system recognize and fight off these bacteria if they are encountered in the future.

  • High-dose Quadrivalent Influenza Vaccine

    is a vaccine that helps protect against four different strains of the influenza virus, commonly known as the flu. This high-dose version is specifically designed for older adults, as their immune systems may not respond as strongly to standard-dose vaccines. By receiving this vaccine, the body is better prepared to fight off the flu, reducing the risk of severe illness.

What is already known about the treatment

ExPEC9V – ExPEC9V is administered as an injection and is currently being studied in clinical trials to assess its effectiveness and safety. It is being developed to prevent invasive diseases caused by extraintestinal pathogenic Escherichia coli (ExPEC) in adults aged 65 years or older. The medication works by stimulating the body's immune system to recognize and fight off the ExPEC bacteria, potentially preventing infections. It is classified as a vaccine, specifically targeting bacterial infections.

Investigated diseases

Invasive Extraintestinal Pathogenic Escherichia coli (ExPEC) Disease – This disease is caused by a type of Escherichia coli bacteria that can invade parts of the body outside the intestines. It often begins when the bacteria enter the bloodstream, leading to infections in various organs. The disease can progress to cause urinary tract infections, bloodstream infections, and infections in other body sites. The bacteria can spread through the body, leading to inflammation and damage in affected areas. The progression of the disease depends on the body's immune response and the virulence of the bacterial strain. It is important to monitor for symptoms of infection, as the bacteria can affect multiple systems in the body.
Trial detailsLast updated 7 Oct 2026
Age65+ yearsPhasePhase IIITrial ID2023-504168-40-00Estimated enrolment932 patientsSponsorJanssen Vaccines & Prevention B.V.

sourced from the EU Clinical Trials Register and site verification

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