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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)

Not Applicable
Recruiting
Conditions
Progressive Metastatic Castrate Resistant Prostate Cancer
Interventions
Drug: Tulmimetostat DL1 QD
Drug: Tulmimetostat DL2 QD
Drug: Tulmimetostat DL3 QD
Drug: Tulmimetostat Doses 1 or 2 QD
Drug: Tulmimetostat RP2D QD
Drug: Standard of Care (SoC)
Drug: JSB462 Dose 1 QD
Drug: JSB462 Dose 2 QD
Drug: JSB462 QD
Registration Number
NCT07206056
Lead Sponsor
Novartis Pharmaceuticals
Brief Summary

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).

Detailed Description

The Phase 1 study, comprised of Parts 1a and 1b, aims to assess the safety and tolerability of the combination of tulmimetostat and JSB462:

1. Part 1a is the parallel dose escalation that aims to determine the recommended dose(s) of tulmimetostat and JSB462, in combination, for further exploration.

2. Part 1b is the dose expansion/optimization that aims to determine the recommended dose of the combination for Phase II.

The purpose of the Phase II study (Part 2) is to compare the combination of tulmimetostat with JSB462 in terms of the biochemical response as assessed by PSA50 compared to the standard of care (SoC) in adult men with progressive, taxane-naive mCRPC.

Recruitment & Eligibility

Status
RECRUITING
Sex
Male
Target Recruitment
188
Inclusion Criteria
  • 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

Key

Exclusion Criteria
  • 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.
  • Known hypersensitivity or contraindication to any of the study treatment components or its excipients or to drugs of similar chemical classes.
  • 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.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Part 1a: Cohort DL1ATulmimetostat DL1 QDTulmimetostat DL1 QD + JSB462 Dose 1 QD
Part 1a: Cohort DL1AJSB462 Dose 1 QDTulmimetostat DL1 QD + JSB462 Dose 1 QD
Part 1a: Cohort DL1BTulmimetostat DL1 QDTulmimetostat DL1 QD + JSB462 Dose 2 QD
Part 1a: Cohort DL1BJSB462 Dose 2 QDTulmimetostat DL1 QD + JSB462 Dose 2 QD
Part 1a: Cohort DL2ATulmimetostat DL2 QDTulmimetostat DL2 QD + JSB462 Dose 1 QD
Part 1a: Cohort DL3AJSB462 Dose 1 QDTulmimetostat DL3 QD + JSB462 Dose 1 QD
Part 1a: Cohort DL3BTulmimetostat DL3 QDTulmimetostat DL3 QD + JSB462 Dose 2 QD
Part 1a: Cohort DL3BJSB462 Dose 2 QDTulmimetostat DL3 QD + JSB462 Dose 2 QD
Part 1a: Cohort DL2AJSB462 Dose 1 QDTulmimetostat DL2 QD + JSB462 Dose 1 QD
Part 1a: Cohort DL2BTulmimetostat DL2 QDTulmimetostat DL2 QD + JSB462 Dose 2 QD
Part 1a: Cohort DL2BJSB462 Dose 2 QDTulmimetostat DL2 QD + JSB462 Dose 2 QD
Part 1a: Cohort DL3ATulmimetostat DL3 QDTulmimetostat DL3 QD + JSB462 Dose 1 QD
Part 1b : Arm ATulmimetostat Doses 1 or 2 QDTulmimetostat Dose 1 QD + JSB462 QD
Part 1b : Arm AJSB462 QDTulmimetostat Dose 1 QD + JSB462 QD
Part 1b: Arm BTulmimetostat Doses 1 or 2 QDTulmimetostat Dose 2 QD + JSB462 QD
Part 1b: Arm BJSB462 QDTulmimetostat Dose 2 QD + JSB462 QD
Part 2: Arm 1Tulmimetostat RP2D QDTulmimetostat RP2D QD + JSB462 QD
Part 2: Arm 1JSB462 QDTulmimetostat RP2D QD + JSB462 QD
Part 2: Arm 2Standard of Care (SoC)Standard of Care at the discretion of the investigator
Primary Outcome Measures
NameTimeMethod
Part 1a: Dose-limiting toxicities (DLTs)Up to 28 days

A dose-limiting toxicity (DLT) is defined as an adverse event or abnormal laboratory value assessed as unrelated to disease, disease progression, inter-current illness/injury, or concomitant medications that occurs within the first 28 days of treatment with tulmimetostat and JSB462 and meets any of the criteria specified in the protocol. The National Cancer Institute Common Terminology Criteria for Adverse events (NCI CTCAE) version 5.0 will be used for all grading. For the purpose of dose-escalation decisions, DLTs will be considered and included in the Bayesian Logistic Regression Model (BLRM).

Part 1a and Part 1b: Incidence rate of Adverse Events (AEs) and Serious Adverse Events (SAEs)From date of randomization till 30 days safety fup, assessed up to approximately 14 months

The analysis of adverse events will include categorization by type, frequency, and severity, as graded by the NCI CTCAE version 5.0.

Part 1a and Part 1b: Number of Participants with dose adjustmentsFrom date of randomization till 30 days safety fup, assessed up to approximately 14 months

The number of participants with dose adjustments (reductions, interruption, or permanent discontinuation) will be summarized by treatment arm.

Part 1a and Part 1b: Dose IntensityFrom date of randomization till 30 days safety fup, assessed up to approximately 14 months

Dose intensity (computed as the ratio of actual cumulative dose received and actual duration of exposure) and the relative dose intensity (computed as the ratio of dose intensity and planned dose intensity) will be summarized by means of descriptive statistics

Part 1a and Part 1b: Duration of exposure to each study drugFrom date of randomization till 30 days safety fup, assessed up to approximately 14 months

The duration of exposure (in months) to Tulmimetostat and JSB462 (Part 1a and Part 1b) will be summarized by means of descriptive statistics

Part 1b and Part 2: prostate-specific antigen 50 (PSA50) at Month 6Month 6

PSA50 is defined as a PSA reduction of at least 50% from baseline at 6 months confirmed by a second PSA measurement ≥ 3 weeks later.

Secondary Outcome Measures
NameTimeMethod
Part 1a and Part 1b: Plasma concentrations of tulmimetostat and JSB462Cycle 1-2: Day 1 (predose/0 hour, 1 hour, 2 hours, 4 hours, 6 hours and 8 hours; Tulmimetostat only: 30 minutes and 3 hours). Cycle 1: Day 2 (24 hours), Days 8 and 15 (predose/0 hour and 2 hours). Cycles 3-5: Day 1 (predose/0 hour). 1 cycle = 28 days.

Tulmimetostat and JSB462 pharmacokinetic (PK) samples will be obtained and evaluated in all participants at all dose levels by treatment arms

Part 2: Plasma concentrations of tulmimetostat and JSB462Cycle 1 and 2: Day 1 (predose/0 hour and 2 hours). Cycles 3-5: Day 1 (predose/0 hour). 1 cycle = 28 days.

Tulmimetostat and JSB462 pharmacokinetic (PK) samples will be obtained and evaluated in all participants at all dose levels by treatment arms

Part 1a and Part 1b: AUC of tulmimetostat and JSB462Cycle 1-2: Day 1 (predose/0 hour, 1 hour, 2 hours, 4 hours, 6 hours and 8 hours; Tulmimetostat only: 30 minutes and 3 hours). Cycle 1: Day 2 (24 hours), Days 8 and 15 (predose/0 hour and 2 hours). Cycles 3-5: Day 1 (predose/0 hour). 1 cycle = 28 days.

Venous whole blood samples will be collected for activity-based pharmacokinetics characterization. Area under the concentration-time curve from time zero to the time of last quantifiable concentration (AUClast) and Area under the concentration-time curve from time zero (pre-dose) extrapolated to infinite time (AUCinf) will be listed and summarized using descriptive statistics.

Part 2: AUC of tulmimetostat and JSB462Cycle 1 and 2: Day 1 (predose/0 hour and 2 hours). Cycles 3-5: Day 1 (predose/0 hour). 1 cycle = 28 days.

Venous whole blood samples will be collected for activity-based pharmacokinetics characterization. Area under the concentration-time curve from time zero to the time of last quantifiable concentration (AUClast) and Area under the concentration-time curve from time zero (pre-dose) extrapolated to infinite time (AUCinf) will be listed and summarized using descriptive statistics.

Part 1a and Part 1b: Cmax of tulmimetostat and JSB462Cycle 1-2: Day 1 (predose/0 hour, 1 hour, 2 hours, 4 hours, 6 hours and 8 hours; Tulmimetostat only: 30 minutes and 3 hours). Cycle 1: Day 2 (24 hours), Days 8 and 15 (predose/0 hour and 2 hours). Cycles 3-5: Day 1 (predose/0 hour). 1 cycle = 28 days.

Venous whole blood samples will be collected for activity-based pharmacokinetics characterization. Cmax will be listed and summarized using descriptive statistics.

Part 2: Cmax of tulmimetostat and JSB462Cycle 1 and 2: Day 1 (predose/0 hour and 2 hours). Cycles 3-5: Day 1 (predose/0 hour). 1 cycle = 28 days.

Venous whole blood samples will be collected for activity-based pharmacokinetics characterization. Cmax will be listed and summarized using descriptive statistics.

Part 1b and Part 2: prostate-specific antigen 50 (PSA50) at 3, 9, and 12 monthsMonth 3, Month 9, Month 12

PSA50 is defined as a PSA reduction of at least 50% from baseline at 3, 9, and 12 months confirmed by a second PSA measurement ≥ 3 weeks later.

Part 1b and Part 2: radiographic progression free survival (rPFS)From date of randomization until date of radiographic progression or date of death from any cause, whichever comes first, assessed up to approximately 15 months

rPFS is defined as time between randomization and the first occurrence of disease progression as per PCWG3-modified RECIST v1.1 or death due to any cause

Part 1b and Part 2: overall survival (OS)From date of randomization until date of death from any cause, assessed up to approximately 15 months

OS is defined as the time between randomization to date of death due to any cause

Part 1b and Part 2: objective response (OR)From date of randomization until date of progression or date of death from any cause, whichever come first, assessed up to approximately 15 months

OR is defined as a confirmed complete response (CR) or partial response (PR) per PCWG3-modified RECIST 1.1 as assessed by the investigator

Part 1b and Part 2: best overall response (BOR)From date of randomization until date of progression or date of death from any cause, whichever come first, assessed up to approximately 15 months

BOR is defined as the best response per Prostate Cancer Working Group 3 (PCWG3)-modified RECIST 1.1 as assessed by the Investigator

Part 1b and Part 2: duration of response (DOR)From date of randomization until date of progression or date of death from any cause, whichever come first, assessed up to approximately 15 months

DOR is defined as time between first documented CR/PR and disease progression or death due to any cause per PCWG3-modified RECIST 1.1 as assessed by the investigator

Part 1b and Part 2: time to first symptomatic skeletal event (TTSSE)From randomization until the first occurrence of a new symptomatic bone fracture, spinal cord compression, tumor-related orthopedic surgery, radiation therapy for bone pain, or death, assessed up to 15 months.

TTSSE is defined as time from randomization to the first new symptomatic pathological bone fracture, spinal cord compression, tumor-related orthopedic surgical intervention, requirement for radiation therapy to relieve bone pain or death from any cause, whichever occurs first.

Part 2: Incidence rate of Adverse Events (AEs) and Serious Adverse Events (SAEs)From date of randomization till 30 days safety fup, assessed up to approximately 15 months

The analysis of adverse events will include categorization by type, frequency, and severity, as graded by the NCI CTCAE version 5.0.

Part 2: Number of Participants with dose adjustmentsFrom date of randomization till 30 days safety fup, assessed up to approximately 15 months

The number of participants with dose adjustments (reductions, interruption, or permanent discontinuation) will be summarized by treatment arm.

Part 2: Dose IntensityFrom date of randomization till 30 days safety fup, assessed up to approximately 15 months

Dose intensity (computed as the ratio of actual cumulative dose received and actual duration of exposure) and the relative dose intensity (computed as the ratio of dose intensity and planned dose intensity) will be summarized by means of descriptive statistics

Part 2: Duration of exposure to each study drugFrom date of randomization till 30 days safety fup, assessed up to approximately 15 months

The duration of exposure (in months) to Tulmimetostat and JSB462 / Standard of Care (SoC) of investigator's choice (Part 2) will be summarized within each strata by means of descriptive statistics

Trial Locations

Locations (1)

Novartis Investigative Site

🇸🇬

Singapore, Singapore

Novartis Investigative Site
🇸🇬Singapore, Singapore

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