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Study of Flu Vaccine and Pembrolizumab for Patients with Early Colorectal Cancer

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 a combination treatment for patients with a specific type of colorectal cancer known as pMMR colorectal cancer. The treatment involves using a flu vaccine injected directly into the tumor and a medication called pembrolizumab, which is also known by its code name MK-3475. Pembrolizumab is a type of immunotherapy, which means it helps the body's immune system fight cancer cells.

The purpose of the study is to see if this combination of treatments can help shrink the tumors in patients with pMMR colorectal cancer. During the study, participants will receive the flu vaccine directly into their tumor and pembrolizumab through an intravenous infusion, which means it is given directly into a vein. The study will monitor how the cancer responds to this treatment over a period of time.

Participants in the study may receive either the combination of the flu vaccine and pembrolizumab or a placebo. The study will also look at the safety of the treatment, including any side effects that might occur. The goal is to determine if this new approach can effectively reduce the size of the tumors and improve outcomes for patients with this type of colorectal cancer.

The research process

The trial runs in 7 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the trial

    Upon joining the trial, you will provide written informed consent, confirming your understanding and agreement to participate in the study.

    You will undergo a series of initial assessments to confirm eligibility, including a review of your medical history and a physical examination.

  2. Step 2

    Initial assessments

    You will have blood tests to check your overall health, including kidney and liver function, and to ensure adequate bone marrow function.

    A pregnancy test will be conducted for women of reproductive potential to confirm a negative result before starting treatment.

  3. Step 3

    Treatment phase

    You will receive a combination of treatments: an intratumoral flu vaccine and an intravenous infusion of pembrolizumab.

    The flu vaccine will be administered directly into the tumor, while pembrolizumab will be given through a vein in your arm.

  4. Step 4

    Monitoring and follow-up

    Regular follow-up visits will be scheduled to monitor your response to the treatment and to check for any side effects.

    Blood samples will be taken periodically for analysis, and imaging tests may be conducted to assess tumor response.

  5. Step 5

    Surgery

    If indicated, you will undergo elective surgery intended to remove the tumor, following the treatment phase.

    The timing of the surgery will be determined based on your response to the treatment and overall health status.

  6. Step 6

    Post-treatment assessments

    After surgery, additional assessments will be conducted to evaluate the effectiveness of the treatment.

    These assessments may include analysis of tumor samples and further blood tests.

  7. Step 7

    End of trial

    The trial will conclude with a final evaluation of your health and any long-term effects of the treatment.

    You will be informed of the overall results of the study and any relevant findings related to your participation.

Who can join the trial?

15 criteria

  • Have a diagnosis of localized **pMMR stage I to III colorectal cancer**. This means the cancer is in the colon or rectum and has not spread to distant parts of the body.
  • Be **18 years of age or older** at the time of signing the consent form.
  • Provide **written informed consent** to participate in the study.
  • Have an **ECOG performance status of 0 or 1**, which indicates that you are fully active or have some symptoms but do not require bed rest during the day.
  • Have **adequate bone marrow function**, which includes:
    • Hemoglobin level of at least 6.2 mmol/L or 10 g/dL.
    • Absolute neutrophil count (ANC) of at least 1.5 × 109/L.
    • Platelet count of at least 100 × 109/L.
    • Have **adequate kidney function**, defined as a glomerular filtration rate (GFR) of at least 60 mL/min or creatinine level not more than 1.5 times the upper limit of normal.
    • Have **adequate liver function**, which includes:
      • Total bilirubin level not more than 1.5 times the upper limit of normal.
      • Alanine aminotransferase (ALT) level not more than 2.5 times the upper limit of normal.
      • Alkaline phosphatase level not more than 2.5 times the upper limit of normal.
      • Have an **indication for elective curative intended surgery** without prior chemotherapy.
      • Use an **acceptable method of contraception** during heterosexual activity while receiving pembrolizumab and for 120 days after the last dose. This applies to both male and female participants.
      • **Women of reproductive potential** must have a negative pregnancy test within 72 hours before receiving pembrolizumab.
      • **Women must not be breastfeeding** during the study.

Who cannot join the trial?

3 criteria

  • Patients who do not have **pMMR type colorectal cancer** cannot participate. pMMR refers to a specific type of genetic makeup in colorectal cancer.
  • Patients who are not within the specified age range cannot participate. The age range is not specified here, but it is important to check if you fall within the eligible age group.
  • Patients who are part of a vulnerable population cannot participate. A vulnerable population includes groups like pregnant women, children, or those unable to give consent.
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Investigated drugs

  • Flu Vaccine

    is typically used to protect against the influenza virus. In this trial, it is being used in a unique way by injecting it directly into the tumor. The idea is that the flu vaccine might help the body's immune system recognize and attack the cancer cells more effectively. This approach is being tested to see if it can help shrink the tumors in patients with a specific type of colorectal cancer.

  • Pembrolizumab

    is a type of immunotherapy. It works by helping the immune system detect and fight cancer cells. Normally, cancer cells can hide from the immune system, but pembrolizumab blocks this hiding mechanism, allowing the immune system to recognize and destroy the cancer cells. In this trial, it is used alongside the flu vaccine to see if the combination can lead to better outcomes for patients with colorectal cancer.

What is already known about the treatment

  • Flu Vaccine

    The flu vaccine is administered as an injection directly into the tumor in this trial. It is currently being studied for its potential to help the immune system fight colorectal cancer. The main therapeutic indication is to stimulate the immune system to attack cancer cells. At the molecular level, the vaccine is thought to activate immune cells that can recognize and destroy cancer cells. It is classified as an immunological agent.

  • Pembrolizumab

    Pembrolizumab is given as an intravenous infusion, meaning it is delivered directly into the bloodstream through a vein. It is an established medication in the treatment of various cancers and is being tested here for its effectiveness in colorectal cancer. The main therapeutic indication is to enhance the body's immune response against cancer cells. At the molecular level, pembrolizumab works by blocking a protein called PD-1, which helps cancer cells hide from the immune system. It is classified as an immune checkpoint inhibitor.

Investigated diseases

Colorectal Cancer – Colorectal cancer is a type of cancer that begins in the colon or rectum, parts of the large intestine. It typically starts as small, noncancerous clumps of cells called polyps that form on the inside of the colon or rectum. Over time, some of these polyps can become cancerous. As the cancer progresses, it can invade and destroy normal tissue nearby and may spread to other parts of the body. The progression of colorectal cancer can vary, with some cases growing slowly over several years. Symptoms may not appear until the cancer has advanced, making regular screenings important for early detection.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-503228-17-00Estimated enrolment21 patientsSponsorRegion Sjaelland

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