Tulmimetostat

Tulmimetostat is being studied in clinical trials for several advanced cancers, including prostate cancer, solid tumors, and lymphomas. These trials are checking safety, dose, and how well the treatment may work, alone or in combination with other cancer medicines. The studies include people with metastatic hormone-sensitive prostate cancer, metastatic castration-resistant prostate cancer, and other advanced cancers.

Table of contents

Clinical trial overview

Tulmimetostat is being studied in interventional clinical trials, which means researchers give a treatment and follow what happens.[1][2][3] The available studies are all listed as Authorised and are testing Tulmimetostat in people with advanced cancers.[1][2][3]

These trials are mainly early-stage studies, with Phase 1 and Phase 2 research.[1][2] Early phases usually focus on safety, dose finding, and whether the treatment can be given in a way that people can tolerate.

Prostate cancer studies

Two of the studies focus on men with advanced prostate cancer.[2][3] One study is in metastatic hormone-sensitive prostate cancer (mHSPC), which means the cancer has spread but still responds to hormone lowering treatment.[2] Another study is in metastatic castrate resistant prostate cancer (mCRPC), which means the cancer has spread and is no longer controlled by lowering testosterone.[3]

The mHSPC study, TulmiSTAR-02, compares Tulmimetostat with darolutamide versus darolutamide alone, and also studies Tulmimetostat with abiraterone.[2] The mCRPC study tests Tulmimetostat with JSB462 and also includes other prostate cancer treatments in the study design, such as abiraterone, enzalutamide, docetaxel, cabazitaxel, and luxdegalutamide.[3]

In the prostate cancer trials, the main results being measured include PSA changes, especially PSA50 and biochemical response rate.[2][3] PSA is a blood test used to help track prostate cancer activity.

Other advanced cancers

One larger study is looking at Tulmimetostat in people with advanced solid tumors and lymphomas.[1] This includes several cancer types such as urothelial carcinoma, ovarian clear cell cancer, endometrial carcinoma, lymphoma, malignant pleural or peritoneal mesothelioma, and metastatic castration-resistant prostate cancer.[1]

This study uses Tulmimetostat alone in some parts and also tests it with enzalutamide in a prostate cancer cohort.[1] The trial is designed to learn both the best dose and the antitumor activity, which means whether the treatment may shrink or control the cancer.[1]

Main trial goals and endpoints

The first goal in the early parts of the studies is to find the safest dose range and the recommended Phase 2 dose or recommended dose for expansion.[1][2][3] A dose-limiting toxicity is a side effect serious enough to limit treatment, and it is measured closely in the first treatment cycles.[1][3]

The studies also measure safety and tolerability by tracking adverse events, lab values, vital signs, electrocardiograms, dose interruptions, dose reductions, and treatment stop rates.[2][3] Tolerability means how well people can stay on treatment without needing major changes.

Later study goals look at efficacy, which means whether the treatment helps the cancer.[1][2][3] In the solid tumor and lymphoma study, the main efficacy endpoint is overall response rate, meaning the share of patients with complete or partial tumor shrinkage.[1] In the prostate cancer studies, the main efficacy endpoints are PSA50 and biochemical response rate at 6 months.[2][3]

Who can take part

The studies are aimed at adults with advanced cancers, but each trial has its own entry rules.[1][2][3] The main groups include people with advanced solid tumors, lymphomas, metastatic hormone-sensitive prostate cancer, and metastatic castration-resistant prostate cancer.[1][2][3]

Some study parts are for monotherapy, which means Tulmimetostat is used by itself, while other parts are for combination therapy, which means it is given with another cancer medicine.[1][2][3] The exact fit depends on the cancer type, the study part, and the treatment already received.

Trial status and size

All three studies listed in the source data are marked Authorised.[1][2][3] The studies are fairly large for early research, with planned enrollment of 275, 149, and 188 participants.[1][2][3]

The larger solid tumor and lymphoma study is Phase 1/2, while the two prostate cancer studies are Phase 1 studies that also include later expansion or comparison parts.[1][2][3] This shows that Tulmimetostat is still being tested to learn the best way to use it in cancer care.

Trial ID Phase Condition studied Status Enrollment
NCT04104776 Phase 1/2 Advanced solid tumors and lymphomas, including prostate cancer and mesothelioma Authorised 275
2025-521873-15-00 Phase 1 Metastatic hormone-sensitive prostate cancer Authorised 149
2025-521880-10-00 Phase 1 Metastatic castration-resistant prostate cancer Authorised 188

Ongoing Clinical Trials on Tulmimetostat

  • A study testing tulmimetostat with darolutamide or abiraterone in patients with metastatic hormone-sensitive prostate cancer

    Recruiting

    1 1 1
    France Germany Hungary Italy Spain
  • A Study of Tulmimetostat and Luxdegalutamide Compared to Standard Treatment in Men with Advanced Prostate Cancer That No Longer Responds to Hormone Therapy

    Recruiting

    1 1 1
    Denmark France Germany Italy Poland Spain
  • Study of Tulmimetostat (CPI-0209) for Patients with Advanced Solid Tumors and Lymphomas

    Recruiting

    1 1 1
    France Italy Poland Spain

Glossary

  • Clinical trial: A research study in people that tests a medical treatment to learn about safety, dose, and how well it works.
  • Interventional study: A study where researchers give a treatment to see what happens.
  • Phase 1: The first main stage of testing in people. It usually looks at safety, side effects, and the best dose.
  • Phase 2: A study stage that looks more closely at whether the treatment may help the cancer.
  • Dose-limiting toxicities (DLTs): Side effects that are serious enough to limit how much of a treatment can be given.
  • Recommended Phase 2 dose (RP2D): The dose chosen for later studies after early safety testing.
  • Recommended dose for expansion (RDE): The dose selected to be tested in a larger group of patients.
  • Adverse events (AEs): Medical problems or unwanted effects that happen during a study.
  • Tolerability: How well people can handle a treatment without too much trouble.
  • Biochemical response rate (BCR): A measure of how much a blood marker, such as PSA, improves after treatment.
  • PSA: Prostate-specific antigen, a blood test used to help track prostate cancer.
  • mCRPC: Metastatic castration-resistant prostate cancer, a prostate cancer that has spread and no longer responds to lowering testosterone.

References

  1. https://clinicaltrials.eu/trial/study-of-tulmimetostat-cpi-0209-for-patients-with-advanced-solid-tumors-and-lymphomas/
  2. https://clinicaltrials.gov/study/2025-521873-15-00
  3. https://clinicaltrials.gov/study/2025-521880-10-00