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Study of Valemetostat Tosylate with Drug Combination for Patients with Previously Treated Solid Tumors

Fast replyInvestigationalNo 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 of medications on different types of solid tumors. The study involves the use of two main treatments: Valemetostat Tosylate, which is taken as a tablet, and DXd Antibody-Drug Conjugates (ADCs), which are given as an infusion. The trial is divided into different parts, each targeting specific types of cancer. One part of the study looks at patients with breast cancer that is difficult to remove surgically or has spread to other parts of the body, specifically those with low levels of a protein called HER2. Another part focuses on patients with advanced or spreading gastric cancer or cancer at the junction of the stomach and esophagus, known as GEJ adenocarcinoma, who have previously been treated with a medication called trastuzumab. The third part of the study involves patients with a type of lung cancer called non-squamous non-small cell lung cancer (NSCLC), which may or may not have specific genetic changes.

The purpose of this study is to assess the safety and effectiveness of the combination of Valemetostat Tosylate and DXd ADCs in treating these cancers. The study is conducted in two phases. The first phase is designed to find the safest dose of the medications when used together, while the second phase aims to evaluate how well the treatment works. Participants will receive the medications and be monitored for any side effects and improvements in their condition. The study will help determine the best dose and gather information on how the treatment affects the cancer.

Throughout the study, participants will undergo regular check-ups and tests to monitor their health and the progress of their cancer. These tests may include imaging scans like computed tomography (CT) or magnetic resonance imaging (MRI) to assess the size and spread of the tumors. The study is expected to continue for several years, providing valuable data on the potential benefits and risks of these treatments for patients with these specific types of cancer.

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

    Initial assessment

    Upon joining the study, an initial assessment will be conducted. This includes a review of your medical history and a physical examination. Imaging tests such as computed tomography (CT) or magnetic resonance imaging (MRI) will be performed to measure any existing tumors.

    You will be required to provide a tumor sample for further analysis. Your performance status will be evaluated using the Eastern Cooperative Oncology Group (ECOG) scale, which assesses your ability to perform daily activities.

  2. Step 2

    Treatment phase 1

    In the first phase of treatment, you will receive a combination of medications. The main medication is valemetostat tosilate, which is taken orally in the form of a film-coated tablet. The dosage and frequency will be determined by the study team based on your specific condition.

    You will also receive trastuzumab deruxtecan or datopotamab deruxtecan through an intravenous infusion. The specific medication and dosage will depend on the sub-protocol you are enrolled in. This phase aims to assess the safety and tolerability of the medication combination.

  3. Step 3

    Monitoring and follow-up

    Throughout the study, regular monitoring will be conducted to assess your response to the treatment. This includes frequent blood tests and imaging studies to track the progress of your condition.

    You will be asked to report any side effects or changes in your health. The study team will evaluate these reports to ensure your safety and adjust treatment as necessary.

  4. Step 4

    Treatment phase 2

    In the second phase of treatment, the focus will be on evaluating the effectiveness of the medication combination. The dosage may be adjusted based on the results from the first phase.

    You will continue to receive valemetostat tosilate orally and either trastuzumab deruxtecan or datopotamab deruxtecan through intravenous infusion. The study team will closely monitor your response to the treatment.

  5. Step 5

    Final evaluation

    At the end of the study, a final evaluation will be conducted. This includes a comprehensive review of your health status and the effectiveness of the treatment.

    The study team will discuss the results with you and provide recommendations for any further treatment or follow-up care that may be necessary.

Who can join the trial?

7 criteria

  • Must be at least 18 years old or the minimum legal adult age in your area.
  • Must have at least one measurable tumor based on imaging tests like CT or MRI.
  • Must be willing to provide a sample of the tumor for testing.
  • Must 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.
  • For Sub-Protocol A: Must have breast cancer that cannot be removed by surgery or has spread to other parts of the body. The cancer must have progressed after hormone therapy if it was hormone receptor-positive. Must have been treated with 1 to 2 prior lines of chemotherapy for cancer that has returned or spread. Must have low HER2 expression, which is a protein that can affect cancer growth.
  • For Sub-Protocol B: Must have gastric or gastroesophageal junction adenocarcinoma that cannot be removed by surgery or has spread, or has progressed after treatment with trastuzumab.
  • For Sub-Protocol C: Must have non-squamous non-small cell lung cancer (NSCLC) at an advanced stage. If you do not have an actionable genomic alteration (AGA), you must have received certain chemotherapy and immunotherapy treatments. If you have an AGA, you must have been treated with targeted therapy and possibly chemotherapy and immunotherapy.

Who cannot join the trial?

7 criteria

  • Patients who have not been previously treated for their condition cannot participate.
  • Patients with a type of cancer that can be surgically removed are not eligible.
  • Patients with cancer that is not advanced or has not spread to other parts of the body cannot join the study.
  • Patients with a type of cancer that does not match the specific requirements of the study are excluded.
  • Patients who are not within the specified age range for the study cannot participate.
  • Patients who are not able to understand or agree to the study requirements are not eligible.
  • Patients who are part of a vulnerable population, such as those unable to give informed consent, are excluded.
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Investigated drugs

  • Valemetostat Tosylate

    is a medication being studied for its potential to treat solid tumors. It works by targeting specific proteins in cancer cells, which may help to stop the growth and spread of the cancer. In this clinical trial, Valemetostat Tosylate is being tested in combination with other treatments to see if it can improve outcomes for patients with solid tumors.

  • DXd ADCs

    are a type of treatment known as antibody-drug conjugates. These are special medications that combine an antibody with a drug. The antibody helps to deliver the drug directly to the cancer cells, which may help to kill the cancer cells more effectively while causing less harm to normal cells. In this trial, DXd ADCs are being used in combination with Valemetostat Tosylate to see if this combination can be more effective in treating solid tumors.

  • T-DXd

    is another type of antibody-drug conjugate being tested in this study. Like other ADCs, it is designed to target cancer cells specifically, delivering a powerful drug directly to them. This approach aims to improve the effectiveness of the treatment while minimizing side effects. In this trial, T-DXd is being combined with Valemetostat Tosylate to evaluate its safety and effectiveness in treating patients with solid tumors.

What is already known about the treatment

Valemetostat Tosylate – Valemetostat Tosylate is administered orally and is currently being studied in clinical trials to evaluate its safety and effectiveness when combined with other drugs for treating certain types of cancer. It is being tested in combination with DXd ADCs for patients with solid tumors, including breast cancer, gastric cancer, and non-small cell lung cancer. The medication works by inhibiting specific enzymes that are involved in cancer cell growth, thereby potentially slowing down or stopping the progression of the disease. Valemetostat Tosylate is classified as a targeted cancer therapy, focusing on specific molecular targets associated with cancer.

Investigated diseases

  • Breast Cancer

    Breast cancer is a disease where cells in the breast grow uncontrollably. It often begins in the ducts or lobules of the breast. As it progresses, it can spread to nearby tissues and lymph nodes. The disease may present as a lump in the breast or changes in breast shape or texture. Over time, it can metastasize to other parts of the body. The progression varies depending on the type and stage of the cancer.

  • Gastric Adenocarcinoma

    Gastric adenocarcinoma is a type of cancer that forms in the lining of the stomach. It typically starts in the glandular cells that produce stomach acids and mucus. As the disease advances, it can invade deeper layers of the stomach wall and spread to nearby organs. Symptoms may include stomach pain, weight loss, and nausea. The cancer can metastasize to distant organs if not managed. The rate of progression can differ based on various factors, including the cancer's location and stage.

  • Gastroesophageal Junction Adenocarcinoma

    This cancer occurs where the esophagus meets the stomach. It originates in the glandular cells of this junction. As it progresses, it can invade surrounding tissues and spread to lymph nodes. Symptoms might include difficulty swallowing and chest pain. The disease can metastasize to other parts of the body. Its progression depends on the cancer's stage and other individual factors.

  • Non-Small Cell Lung Cancer

    Non-small cell lung cancer (NSCLC) is a group of lung cancers that behave similarly. It usually starts in the epithelial cells lining the lungs. As it progresses, it can invade nearby tissues and spread to lymph nodes and other organs. Symptoms may include a persistent cough, chest pain, and shortness of breath. The disease can metastasize to distant parts of the body. The progression rate varies based on the cancer's type and stage.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase ITrial ID2024-516916-93-00Protocol codeDS3201-324Estimated enrolment210 patientsSponsorDaiichi Sankyo Inc.

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