Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Recruiting

Study of Trastuzumab Deruxtecan and Drug Combination for Patients with Advanced or Metastatic HER2-Positive Gastric or Gastroesophageal Junction Cancer

Verified siteRegistered 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 treatments for HER2-positive gastric or gastroesophageal junction cancer, which is a type of cancer that affects the stomach and the area where the stomach meets the esophagus. The study will explore the effectiveness of a new treatment combination involving Trastuzumab Deruxtecan (also known as Enhertu®) along with chemotherapy, with or without the addition of Pembrolizumab. The trial will compare this new combination to the current standard treatment, which includes chemotherapy and Trastuzumab, with or without Pembrolizumab.

The purpose of the study is to determine how well these treatments work in patients who have not received prior treatment for their advanced cancer. Participants will receive their treatment through an intravenous injection, which means the medication is given directly into a vein. The study will last for a period of up to 60 weeks, during which participants will be monitored regularly to assess the progress of their cancer and any side effects they may experience.

Throughout the study, participants will undergo various assessments, including imaging tests like MRI or CT scans, to evaluate the size and spread of the cancer. The trial aims to provide valuable information on the potential benefits of the new treatment combination, which could lead to improved outcomes for patients with this type of cancer. Participants will be closely monitored by healthcare professionals to ensure their safety and well-being during the trial.

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 trial

    Upon joining the trial, you will be randomly assigned to one of the treatment groups. This means you will receive a specific combination of medications as part of the study.

  2. Step 2

    Treatment administration

    You will receive medications through different methods. Some medications will be given as an intravenous injection, which means they will be administered directly into your vein. These include cisplatin, oxaliplatin, trastuzumab deruxtecan, trastuzumab, pembrolizumab, and fluorouracil.

    Other medications, such as capecitabine, will be taken orally, meaning you will swallow them as pills.

  3. Step 3

    Medication schedule

    The medications will be given in cycles. Each cycle lasts for a specific period, and you will receive the medications at set times during each cycle. The exact schedule, including dosage and frequency, will be explained to you by the medical team.

  4. Step 4

    Monitoring and assessments

    Throughout the trial, your health will be closely monitored. This includes regular visits to the clinic for check-ups, blood tests, and imaging tests like CT or MRI scans to assess how the treatment is working.

    You will also be asked to complete questionnaires about your well-being and any side effects you may experience.

  5. Step 5

    End of treatment

    The treatment will continue until the end of the trial period or until it is determined that the treatment is no longer beneficial for you. The medical team will discuss the next steps with you at that time.

Who can join the trial?

16 criteria

  • Sign and date the necessary consent forms before any trial-specific procedures begin.
  • Have adequate organ and bone marrow function within 14 days before starting the trial. This means your organs and bone marrow are working well enough to participate.
  • Have a sufficient break from previous treatments before starting the trial.
  • If you can have children, agree to use a highly effective form of birth control or avoid intercourse during the trial and for a specified time after the last dose of the trial medication.
  • Men must not freeze or donate sperm during the trial and for at least 4 months after the last dose of the trial medication.
  • Women must not donate or retrieve eggs during the trial and for at least 7 months after the last dose of the trial medication. They should also not breastfeed during this time.
  • Be willing and able to attend scheduled visits, follow the trial plan, and complete required tests and procedures.
  • Be willing and able to participate in the collection of Patient-Reported Outcomes (PRO) data, which involves answering questions about your health and well-being.
  • Be at least 18 years old on the day of signing the consent form.
  • Have a type of stomach or gastroesophageal cancer that has not been treated before and cannot be removed by surgery.
  • Have cancer that is HER2-positive, which means the cancer cells have more HER2 protein than normal, as confirmed by a specific test.
  • Have a tumor sample tested for PD-L1 expression, which is a protein that can affect the immune system's response to cancer.
  • Provide a tumor sample for testing to determine HER2 and PD-L1 status.
  • Have at least one measurable tumor that can be seen on a CT or MRI scan.
  • Have a Left Ventricular Ejection Fraction (LVEF) of at least 50% within 28 days before starting the trial. LVEF is a measure of how well your heart pumps blood.
  • Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, which means you are fully active or have some symptoms but do not need bed rest during the day.

Who cannot join the trial?

10 criteria

  • Patients with other types of cancer that are not related to the study.
  • Patients who have had another cancer treatment within a certain period before the study.
  • Patients with serious heart problems.
  • Patients with uncontrolled high blood pressure.
  • Patients with active infections that need treatment.
  • Patients who are pregnant or breastfeeding.
  • Patients who have allergies to the study medication.
  • Patients with a history of severe allergic reactions.
  • Patients with a history of drug or alcohol abuse.
  • Patients who are unable to follow the study procedures.
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

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

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

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

  • Trastuzumab Deruxtecan (Enhertu®)

    is a medication used in this trial to treat certain types of cancer. It is a combination of two parts: one part targets cancer cells that have a protein called HER2, and the other part helps to kill these cancer cells. This medication is being tested to see if it can help people with advanced stomach cancer or cancer at the junction of the stomach and esophagus.

  • Pembrolizumab

    is a type of therapy known as immunotherapy. It works by helping your immune system recognize and attack cancer cells. In this trial, it is being used to see if it can improve the treatment of advanced stomach cancer when combined with other medications.

  • Trastuzumab

    is another medication used in this trial. It targets the HER2 protein on cancer cells, similar to Trastuzumab Deruxtecan. By attaching to this protein, it can help slow down or stop the growth of cancer cells. This trial is testing its effectiveness in combination with other treatments for advanced stomach cancer.

What is already known about the treatment

Trastuzumab Deruxtecan (Enhertu®) – This medication is administered through an intravenous infusion, meaning it is given directly into the bloodstream through a vein. It is currently being studied in clinical trials for its effectiveness in treating certain types of stomach cancer that are advanced and cannot be removed by surgery, specifically those that are HER2-positive. The drug works by targeting and binding to the HER2 protein on cancer cells, delivering a chemotherapy agent directly to these cells to help destroy them. It is classified as an antibody-drug conjugate, which combines a targeted therapy with chemotherapy to enhance its cancer-fighting effects.

Investigated diseases

Unresectable, Locally Advanced or Metastatic HER2 positive Gastric or Gastroesophageal Junction Cancer – This type of cancer occurs in the stomach or the area where the stomach meets the esophagus, known as the gastroesophageal junction. It is characterized by the overexpression of the HER2 protein, which promotes the growth of cancer cells. The disease is considered unresectable when it cannot be removed completely through surgery. As it progresses, the cancer may spread to nearby tissues and organs, becoming locally advanced. In metastatic cases, the cancer cells travel to distant parts of the body, forming new tumors. The progression of this cancer can lead to symptoms such as difficulty swallowing, weight loss, and abdominal pain.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-513122-27-00Protocol codeDS8201-724Estimated enrolment726 patientsSponsorDaiichi Sankyo Inc.

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.