Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not recruiting

Study of Pembrolizumab for Patients with Locally Advanced, Unresectable, Non-Metastatic Colorectal Cancer

Registered drugNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

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

This clinical trial is focused on studying a type of colon cancer known as locally advanced, irresectable dMMR colorectal cancer. This form of cancer is characterized by its inability to be removed through surgery and is associated with a specific genetic feature called dMMR, which stands for mismatch repair deficiency. The study is investigating the effects of a medication called pembrolizumab, which is also known by its brand name, KEYTRUDA. Pembrolizumab is administered as a solution through an intravenous infusion, meaning it is given directly into the bloodstream through a vein.

The purpose of the study is to evaluate how effective pembrolizumab is in treating patients with this specific type of colorectal cancer. Participants in the study will receive pembrolizumab and will be monitored over a period of time to assess their response to the treatment. The study will also involve regular medical check-ups and imaging tests to track the progress of the cancer and the effects of the medication.

Throughout the study, researchers will be looking at various outcomes, such as the rate at which the cancer responds to the treatment and any changes in the size of the tumor. The study aims to gather information that could help in understanding how pembrolizumab works in treating this type of cancer and potentially improve treatment options for patients in the future.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes a review of medical history and a physical examination.

    A CT scan is performed within 28 days prior to registration to ensure there are no signs of distant metastases.

  2. Step 2

    Screening tests

    Screening laboratory tests are conducted within 10 days prior to the start of the study intervention. These tests include blood counts, liver function tests, and kidney function tests.

    A pregnancy test is required for women of childbearing potential within 72 hours prior to registration.

  3. Step 3

    Treatment administration

    The treatment involves the administration of pembrolizumab, which is provided as a solution for infusion under the brand name KEYTRUDA.

    Pembrolizumab is administered through an intravenous infusion. The dosage and frequency are determined by the study protocol and the healthcare provider.

  4. Step 4

    Monitoring and follow-up

    Regular monitoring is conducted to assess the response to treatment. This includes physical examinations and imaging studies such as CT scans.

    Blood tests are performed periodically to monitor health status and detect any potential side effects.

  5. Step 5

    End of treatment evaluation

    At the end of the treatment period, a comprehensive evaluation is conducted to determine the effectiveness of the treatment.

    This evaluation includes imaging studies and possibly a surgical assessment if applicable.

  6. Step 6

    Long-term follow-up

    After the treatment phase, long-term follow-up is conducted according to local and national guidelines to monitor for disease recurrence or progression.

    Follow-up may include regular medical check-ups and imaging studies.

Who can join the trial?

13 criteria

  • You must sign a written informed consent form, which means you agree to participate in the study after understanding all the details.
  • If you are a male participant, you must agree to use contraception during the treatment period and for at least 200 days after the last dose of the study treatment. You should also refrain from donating sperm during this time.
  • If you are a woman who can have children, you must have a negative pregnancy test within 72 hours before joining the study. If the urine test is positive or unclear, a blood test will be needed.
  • If you are a female participant, you can join if you are not pregnant, not breastfeeding, and meet one of these conditions: You cannot have children, or you agree to use contraception during the treatment period and for at least 120 days after the last dose of the study treatment.
  • A CT scan, which is a special type of X-ray, must be done within 28 days before joining the study.
  • You must be at least 18 years old.
  • You must have a type of colorectal cancer that is locally advanced and cannot be removed by surgery. This means the cancer is in the colon or rectum and has spread to nearby areas, making surgery difficult or requiring additional treatment before surgery can be considered.
  • Your cancer must be confirmed to have a specific characteristic called microsatellite instability-high (MSI-H) or MMR-deficient (dMMR), which are specific changes in the cancer cells.
  • You must not have signs of cancer spreading to distant parts of the body, as shown by a CT scan and physical examination.
  • You must not be eligible for standard first-line treatment with pembrolizumab for metastatic disease, which means cancer that has spread to other parts of the body.
  • You must not be eligible for the NICHE study, which is for patients whose cancer can be removed with relatively minor surgery.
  • You must have an ECOG performance status of 0 or 1, which is a scale used to assess how well you can perform daily activities. This evaluation must be done within 7 days before the first dose of the study treatment.
  • Your screening laboratory tests must meet specific criteria, which include certain levels of blood cells, kidney function, liver function, and blood clotting ability. These tests should be done within 10 days before starting the study treatment.

Who cannot join the trial?

10 criteria

  • Patients who have had another type of cancer in the past, unless it was treated and has not come back for at least 5 years.
  • Patients who have an active infection that requires treatment with antibiotics, antivirals, or antifungals.
  • Patients who have a known allergy to pembrolizumab or any of its ingredients.
  • Patients who are pregnant or breastfeeding.
  • Patients who have an autoimmune disease, which is when the body's immune system attacks its own healthy cells.
  • Patients who have received a live vaccine within 30 days before the start of the study. A live vaccine contains a small amount of the actual virus or bacteria.
  • Patients who have a history of organ transplant, which is when an organ from another person is placed into the patient's body.
  • Patients who have a condition that requires treatment with steroids or other drugs that suppress the immune system.
  • Patients who have a serious heart condition, such as heart failure or a recent heart attack.
  • Patients who have a serious lung condition, such as severe asthma or chronic obstructive pulmonary disease (COPD).
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

Pembrolizumab is a medication used in this trial to treat patients with a specific type of colorectal cancer that is locally advanced and cannot be surgically removed. It works by helping the immune system recognize and attack cancer cells. This study aims to evaluate how effective pembrolizumab is for patients with this particular condition.

What is already known about the treatment

Pembrolizumab – Pembrolizumab is administered as an intravenous infusion, typically given in a clinical setting. It is currently well-established in medical literature and is approved for use in various cancers, including certain types of colorectal cancer. The main therapeutic indication for pembrolizumab in this context is for treating locally advanced, irresectable, non-metastatic colorectal cancers with a specific genetic feature known as dMMR. At the molecular level, pembrolizumab works by blocking a protein called PD-1 on immune cells, which helps the immune system recognize and attack cancer cells more effectively. It is classified as an immune checkpoint inhibitor, a type of immunotherapy.

Investigated diseases

Colorectal Cancer – Colorectal cancer is a type of cancer that begins in the colon or rectum, parts of the large intestine. It often starts as small, benign clumps of cells called polyps, which can develop into cancer over time. When the cancer is locally advanced and irresectable, it means the tumor has grown into nearby tissues or organs and cannot be removed surgically. This type of cancer may exhibit a deficiency in mismatch repair (dMMR), a condition where the cells have a reduced ability to repair DNA errors. As the disease progresses, it can cause symptoms like changes in bowel habits, blood in the stool, and abdominal discomfort. The progression of the disease can vary, and it may spread to other parts of the body if not managed.
Trial detailsLast updated 9 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-509707-32-00Estimated enrolment25 patientsSponsorHet Nederlands Kanker Instituut-Antoni van Leeuwenhoek Ziekenhuis Stichting

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.