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Study of Long-term Safety of Tazemetostat in Patients Who Previously Participated in Tazemetostat Clinical Trials

Verified siteInvestigationalNo placebo
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What is this trial about?

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

This study focuses on evaluating a medication called tazemetostat, which is given as a film-coated tablet taken by mouth. The study aims to assess the long-term safety of this medication in patients who have previously been treated with tazemetostat in other clinical trials and have shown benefit from the treatment.

The study will monitor patients who continue taking tazemetostat either alone or in combination with other approved or experimental medications. During the study, researchers will track any side effects that may occur and how well patients tolerate the medication over an extended period. The medication will be provided according to each patient's previous treatment plan.

Participants will be monitored for various health measures, including their blood cell counts, kidney function, and liver function. The study will also track how long patients survive while receiving the treatment. This is an open-label study, which means all participants will receive the active medication, and there is no use of a placebo.

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 eligibility verification

    You must be currently receiving or have previously received tazemetostat treatment with proven clinical benefit

    Your life expectancy needs to be more than 3 months

    Your blood tests must show adequate bone marrow, kidney, and liver function

  2. Step 2

    Medical screening for women

    If you are a woman who can become pregnant, you will need a negative pregnancy test

    You must agree to use both a highly effective birth control method (such as implants, pills, or IUDs) and a barrier method (such as condoms) during treatment and for 6 months after the last dose

  3. Step 3

    Medical screening for men

    If you are male, you must either have had a vasectomy and use condoms, or you and your partner must use effective birth control during treatment and for 3 months after the last dose

  4. Step 4

    Treatment administration

    You will receive tazemetostat as film-coated tablets for oral use

    The dosage will follow the same pattern as in your previous treatment program

    The treatment will continue as long as you show clinical benefit

  5. Step 5

    Monitoring period

    Your health status will be regularly monitored to check for any side effects

    The study team will track how long you take the medication

    Your survival status will be monitored throughout the study period

  6. Step 6

    Study duration

    The study is planned to continue until September 2025

    Your participation duration will depend on your individual response to treatment and any side effects you may experience

Who can join the trial?

8 criteria

  • Must be currently benefiting from treatment with tazemetostat (a medication used in the study)
  • Must be currently receiving tazemetostat either alone or in combination with other medications as part of a clinical trial
  • Must be willing and able to provide written informed consent and follow all study requirements
  • Must have a life expectancy of more than 3 months
  • Must have adequate: - Blood cell counts - Bone marrow function - Blood clotting factors - Kidney function - Liver function
  • For female participants who can become pregnant: - Must have a negative pregnancy test at study entry - Must use both a highly effective birth control method (such as implants, injections, birth control pills, or IUDs) and a barrier method (such as condoms) during treatment and for 6 months after
  • Women who cannot become pregnant (due to menopause, hysterectomy, or removal of ovaries) do not need pregnancy testing
  • For male participants: - Must have had a successful vasectomy and remain abstinent or use effective contraception - Must use condoms throughout the study and for 3 months after stopping treatment - Or their female partner must meet the above contraception requirements

Who cannot join the trial?

10 criteria

  • Patients who are not currently receiving tazemetostat treatment in a previous clinical study
  • Patients who have experienced severe side effects during previous treatment with tazemetostat
  • Patients who are unable to comply with the long-term safety monitoring requirements
  • Patients who have developed any medical condition that makes continued treatment unsafe
  • Patients who have withdrawn consent from their previous tazemetostat study
  • Patients who have missed scheduled doses or failed to follow study procedures in their previous trial
  • Patients who have developed progressive disease while on tazemetostat treatment
  • Patients who are participating in other clinical trials simultaneously
  • Patients who have developed any contraindications to tazemetostat treatment
  • Patients who cannot continue long-term follow-up visits as required by the study protocol
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Investigated drugs

Tazemetostat is a medication that works by targeting specific enzymes in cancer cells. It belongs to a class of drugs called EZH2 inhibitors, which help control the growth of certain types of cancer cells. This medication is being studied for long-term safety in patients who have previously participated in other tazemetostat clinical trials.

What is already known about the treatment

Tazemetostat - An oral medication administered in tablet form that belongs to the class of EZH2 inhibitors, which are used in cancer treatment. This drug works by blocking the EZH2 protein, which plays a crucial role in controlling gene expression and cancer cell growth. Tazemetostat is primarily used in the treatment of certain types of lymphomas and solid tumors, showing particular effectiveness in patients with specific genetic mutations. The medication represents an innovative approach in targeted cancer therapy, with ongoing clinical trials evaluating its long-term safety and effectiveness in various oncological conditions.

Investigated diseases

Based on the provided source data, there isn't enough specific information about diseases to create disease descriptions. The trial data only mentions that subjects will receive tazemetostat treatment, but does not specify the medical conditions being treated. Without clear disease information from the source data, I cannot provide accurate disease descriptions in the requested format. To create accurate disease descriptions, I would need specific disease names or conditions mentioned in the source data. The current data focuses on a medication trial's objectives and endpoints rather than describing specific medical conditions.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-510553-41-00Protocol codeEZH-501Estimated enrolment100 patientsSponsorEpizyme Inc.

sourced from the EU Clinical Trials Register and site verification

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