Under construction – not a live service
Sign in
Taking people in ItalyPhase 1/2

Tests tulmimetostat with luxdegalutamide in advanced prostate cancer

Tests tulmimetostat and luxdegalutamide together in adults with advanced prostate cancer.

Key facts

Who runs it
Novartis Pharmaceuticals
Where
Milan, Orbassano, and Padova, ItalySee the 3 sitesAlso in 13 other countries, 33 sites
Trial code
Registry title
An Open-label Dose Escalation and Expansion, Followed by a Phase II Study of Tulmimetostat (DZR123) and JSB462 (Luxdegalutamide) in Patients With Progressive Metastatic Castrate Resistant Prostate Cancer (mCRPC) (TulmiSTAR-01)
Status
Recruiting
Phase
Phase 1/2
People taking part
188 people, planned
Started
15 Oct 2025
Expected to end
1 Dec 2030
Type of study
Interventional, 10 groupsOne group gets an existing treatment, for comparison.
Treatments tested
  • Tulmimetostat DL1 QD
  • Tulmimetostat DL2 QD
  • Tulmimetostat DL3 QD
  • Tulmimetostat Doses 1 or 2 QD
  • Tulmimetostat RP2D QD
  • JSB462 Dose 1 QD
  • JSB462 Dose 2 QD
  • JSB462 QD
  • Standard of Care (SoC)
Record updated
9 October 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for men with prostate cancer that has spread, keeps growing, and no longer responds to hormone-lowering treatment. They must have already tried a second-generation hormone therapy.

Age
18 years or older
Sex
Men only
Disease stage
Progressive metastatic castrate resistant prostate cancer (mCRPC): adenocarcinoma of the prostate without neuroendocrine or small cell features, with at least 1 metastatic lesion on a scan taken within 28 days before treatment or randomization, and castrate-level testosterone (below 50 ng/dL or below 1.7 nmol/L).
Earlier treatment
Must have progressed on a prior second-generation ARPI (abiraterone, enzalutamide, darolutamide, or apalutamide). Part 1a and 1b: at least one such drug. Part 2: one such drug. Chemotherapy limits depend on the part: Part 1a up to 2 prior lines in CRPC, Part 1b up to 1 line in CRPC, Part 2 no taxane in mCRPC (chemotherapy allowed in the hormone-sensitive stage).
Biomarker or test result
Castrate level of testosterone in the blood: below 50 ng/dL or below 1.7 nmol/L.

Main reasons for not taking part

  • Earlier treatment with a PRC2 inhibitor (including EZH2 or EED inhibitors)
  • Earlier treatment with a protein degrader drug that targets the androgen receptor (AR)
  • Known allergy to any study treatment component or similar drugs
  • Any investigational drug within 28 days (or 5 half-lives, whichever is longer) before the trial
  • Earlier radioligand therapy in mCRPC (except in Part 1a)

The registry criteria, word for word

Show all 14 criteriaShow less

Who can take part

  • Participant is an adult man ≥ 18 years of age
  • Participant must have histologically and/or cytologically confirmed adenocarcinoma of the prostate without neuroendocrine or small cell features (current or prior biopsy of the prostate and/or metastatic site)
  • Participant must have ≥ 1 metastatic lesion that is present on screening/baseline CT, MRI, or bone scan imaging obtained ≤ 28 days prior to start of treatment (Part 1a dose escalation) or randomization (Part 1b dose expansion and Part 2)
  • Participant must have progressive mCRPC
  • Participant must have a castrate level of serum/plasma testosterone (< 50 ng/dL or < 1.7 nmol/L)
  • Prior ARPI therapy:; Part 1a and 1b only: must have progressed on at least one prior second generation ARPI (abiraterone, enzalutamide, darolutamide, or apalutamide); Part 2 only: must have progressed on one prior second generation ARPI (abiraterone, enzalutamide, darolutamide, or apalutamide)
  • Prior chemotherapy:; Part 1a dose escalation only: may have received ≤ 2 prior lines of chemotherapy in CRPC setting. Note: Prior chemotherapy is permitted in the HSPC setting; Part 1b dose expansion/optimization only: may have received up to one prior line of chemotherapy in CRPC setting. Note: Prior chemotherapy is permitted in the HSPC setting; Part 2 only: Participants must be taxane-naïve in mCRPC setting; prior chemotherapy permitted in HSPC setting only

Who cannot take part

  • Previous treatment with any PRC2 inhibitor, including but not limited to EZH2 inhibitors, EZH2/1 inhibitors, or embryonic ectoderm development (EED) inhibitors
  • Previous treatment with a protein degrader compound that targets the AR
  • Treatment with any investigational agent within 28 days (or 5 half-lives, whichever is longer) prior to study entry
  • Previous treatment with radioligand therapy in the mCRPC setting, except in Part 1a where participants may have received RLT in mCRPC setting
  • Participants with evidence of mCRPC or biochemical recurrence / PSA only disease or asymptomatic prostate cancer without known metastatic disease and with no requirement for therapy and with normal PSA for ≥ 1 year prior to study entry
  • Participants with a history of CNS metastases must have received therapy (surgery, radiotherapy, gamma knife) and be neurologically stable, asymptomatic, and not receiving corticosteroids for the purpose of maintaining neurologic integrity. Those with leptomeningeal disease are eligible if those areas have been treated, are stable, and no neurological impairment is present. For those with parenchymal CNS metastasis (or a history of CNS metastasis), baseline and subsequent radiological imaging must include evaluation of the brain with MRI (preferred) or CT with contrast; Other protocol-defined inclusion/exclusion criteria may apply
  • Known hypersensitivity or contraindication to any of the study treatment components or its excipients or to drugs of similar chemical classes

Where in Italy

Also in 13 other countries, 33 sites

  • Fondazione IRCCS - Istituto Nazionale dei TumoriMilan, ItalyTaking people
  • Azienda Ospedaliero-Universitaria San Luigi GonzagaOrbassano, ItalyTaking people
  • Istituto Oncologico VenetoPadova, ItalyTaking people

About the trial

What the trial wants to find out

This is a two-part, Phase I/II, open-label, global, multicenter study assessing the safety and efficacy of the combination of tulmimetostat (DZR123) and JSB462 (luxdegalutamide) versus standard of care in participants with progressive metastatic castrate resistant prostate cancer (mCRPC).

The 10 groups in the trial

  • Part 1a: Cohort DL1ATreatment being tested

    Tulmimetostat DL1 QD + JSB462 Dose 1 QD

    Treatment: Tulmimetostat DL1 QD and JSB462 Dose 1 QD

  • Part 1a: Cohort DL1BTreatment being tested

    Tulmimetostat DL1 QD + JSB462 Dose 2 QD

    Treatment: Tulmimetostat DL1 QD and JSB462 Dose 2 QD

  • Part 1a: Cohort DL2ATreatment being tested

    Tulmimetostat DL2 QD + JSB462 Dose 1 QD

    Treatment: Tulmimetostat DL2 QD and JSB462 Dose 1 QD

  • Part 1a: Cohort DL2BTreatment being tested

    Tulmimetostat DL2 QD + JSB462 Dose 2 QD

    Treatment: Tulmimetostat DL2 QD and JSB462 Dose 2 QD

  • Part 1a: Cohort DL3ATreatment being tested

    Tulmimetostat DL3 QD + JSB462 Dose 1 QD

    Treatment: Tulmimetostat DL3 QD and JSB462 Dose 1 QD

  • Part 1a: Cohort DL3BTreatment being tested

    Tulmimetostat DL3 QD + JSB462 Dose 2 QD

    Treatment: Tulmimetostat DL3 QD and JSB462 Dose 2 QD

  • Part 1b : Arm ATreatment being tested

    Tulmimetostat Dose 1 QD + JSB462 QD

    Treatment: Tulmimetostat Doses 1 or 2 QD and JSB462 QD

  • Part 1b: Arm BTreatment being tested

    Tulmimetostat Dose 2 QD + JSB462 QD

    Treatment: Tulmimetostat Doses 1 or 2 QD and JSB462 QD

  • Part 2: Arm 1Treatment being tested

    Tulmimetostat RP2D QD + JSB462 QD

    Treatment: Tulmimetostat RP2D QD and JSB462 QD

  • Part 2: Arm 2Existing treatment, for comparison

    Standard of Care at the discretion of the investigator

    Treatment: Standard of Care (SoC)

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov and on the EU's official list of trials (CTIS).
Official title
TulmiSTAR-01: A Two-part, Phase I Dose Escalation and Expansion Followed by a Randomized, Open-label Multicenter, Phase II Study to Assess the Safety and Efficacy of the Combination of Tulmimetostat (DZR123) and JSB462 (Luxdegalutamide) vs Standard of Care in Patients With Progressive Metastatic Castrate Resistant Prostate Cancer
Plain-language title
Tests tulmimetostat with luxdegalutamide in advanced prostate cancerGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 12 November 2026.
Record updated
9 October 2026