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ZEN003694 and Enzalutamide Versus Enzalutamide Monotherapy in Metastatic Castration-Resistant Prostate Cancer

Phase 2
Recruiting
Conditions
Metastatic Castration-Resistant Prostate Cancer
Interventions
Registration Number
NCT04986423
Lead Sponsor
Zenith Epigenetics
Brief Summary

This is an open-label, randomized, Phase 2b study of ZEN003694 in combination with enzalutamide vs. enzalutamide monotherapy in patients with mCRPC who have progressed on prior abiraterone by PCWG3 criteria. Disease must have progressed on only abiraterone by PCWG3 criteria prior to study entry.

The patient population will be separated into two cohorts:

Cohort A: Patients with poor response to prior abiraterone defined as:

* Abiraterone started in hormone-sensitive prostate cancer (HSPC) disease setting: \< 12 months duration on abiraterone or failure to achieve PSA nadir of 0.2 ng/mL while taking abiraterone, or;

* Abiraterone started in castrate-resistant prostate cancer (CRPC) disease setting: \< 6 months duration on abiraterone or failure to achieve PSA50 response while on abiraterone

Cohort B: Patients with response to prior abiraterone, defined as:

* Abiraterone started in hormone-sensitive prostate cancer (HSPC) disease setting: ≥ 12 months duration on abiraterone and nadir PSA \< 0.2 ng/mL, or;

* Abiraterone started in castrate-resistant prostate cancer (CRPC) disease setting: ≥ 6 months duration on abiraterone and confirmed PSA50 response

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
Male
Target Recruitment
200
Inclusion Criteria
  1. Males age ≥ 18 years

  2. Metastatic, castration-resistant, histologically confirmed prostate cancer

  3. Surgical castration or continuous medical castration for ≥ 8 weeks prior to screening; serum testosterone < 50 ng/dL confirmed within 4 weeks of first administration of study drug

  4. Have progressed on prior abiraterone treatment by PCWG3 criteria

  5. Patients who are not candidates for chemotherapy in the opinion of the investigator or patients who decline chemotherapy

  6. Cohort A only - Patient must meet definition of poor responder to abiraterone by one of the following:

    1. Abiraterone started in hormone-sensitive prostate cancer (HSPC) disease setting: < 12 months duration on abiraterone or failure to achieve PSA nadir of 0.2 ng/mL while taking abiraterone
    2. Abiraterone started in castrate-resistant prostate cancer (CRPC) disease setting: < 6 months duration on abiraterone or failure to achieve a PSA50 response
  7. Cohort B only - Patient must meet definition of responder to abiraterone by one of the following:

    1. Abiraterone started in hormone-sensitive prostate cancer (HSPC) disease setting: ≥ 12 months duration on abiraterone and nadir PSA < 0.2 ng/mL
    2. Abiraterone started in castrate-resistant prostate cancer (CRPC) disease setting: ≥ 6 months duration on abiraterone and PSA50 response
  8. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

Exclusion Criteria
  1. Any history of brain metastases, prior seizure, conditions predisposing to seizure activity
  2. Have previously received an investigational BET inhibitor (including previous participation in this study or a study of ZEN003694)
  3. Receipt of prior second-generation androgen receptor inhibitors (e.g. enzalutamide, apalutamide, darolutamide, proxalutamide). Receipt of first-generation AR antagonists (e.g. bicalutamide, nilutamide, flutamide) does not count towards this limit.
  4. Have received prior chemotherapy in the metastatic castration-resistant setting (prior chemotherapy in the hormone-sensitive setting is allowed provided last dose was at least 6 months prior to first dose of study drug)
  5. Have received prior systemic anti-cancer therapy within 2 weeks or five half-lives, whichever is shorter, prior to the first administration of study drug
  6. Have received exogenous administration of testosterone therapy since discontinuation of abiraterone.
  7. Failure to recover to Grade 1 or lower toxicity related to prior systemic therapy (excluding alopecia and neuropathy) prior to study entry
  8. Radiation therapy within 2 weeks of the first administration of study drug

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Cohort A - ZEN003694 + EnzalutamideZEN003694Patients will be administered enzalutamide (160 mg) orally once daily for 21 days prior to the initiation of the combination therapy (Lead-in) to reach steady state concentration (Css) prior to Cycle 1. After the Lead-in, ZEN003694 (72 mg) will be administered orally one daily in combination with daily enzalutamide for 28-day cycles.
Cohort B - ZEN003694 + EnzalutamideZEN003694Patients will be administered enzalutamide (160 mg) orally once daily for 21 days prior to the initiation of the combination therapy (Lead-in) to reach steady state concentration (Css) prior to Cycle 1. After the Lead-in, ZEN003694 (72 mg) will be administered orally one daily in combination with daily enzalutamide for 28-day cycles.
Cohort A - ZEN003694 + EnzalutamideEnzalutamidePatients will be administered enzalutamide (160 mg) orally once daily for 21 days prior to the initiation of the combination therapy (Lead-in) to reach steady state concentration (Css) prior to Cycle 1. After the Lead-in, ZEN003694 (72 mg) will be administered orally one daily in combination with daily enzalutamide for 28-day cycles.
Cohort A - EnzalutamideEnzalutamidePatients will be administered enzalutamide (160 mg) orally once daily for 21 days prior to Cycle 1 Day 1 (Lead-in). After the Lead-in, patients will be administered enzalutamide 160 mg orally once daily for 28-day cycles. Active control patients will have the option to cross-over to treatment with ZEN003694 in combination with enzalutamide upon confirmed radiographic progression by PCWG3 criteria by independent central review.
Cohort B - ZEN003694 + EnzalutamideEnzalutamidePatients will be administered enzalutamide (160 mg) orally once daily for 21 days prior to the initiation of the combination therapy (Lead-in) to reach steady state concentration (Css) prior to Cycle 1. After the Lead-in, ZEN003694 (72 mg) will be administered orally one daily in combination with daily enzalutamide for 28-day cycles.
Cohort B - EnzalutamideEnzalutamidePatients will be administered enzalutamide (160 mg) orally once daily for 21 days prior to Cycle 1 Day 1 (Lead-in). After the Lead-in, patients will be administered enzalutamide 160 mg orally once daily for 28-day cycles. Active control patients will have the option to cross-over to treatment with ZEN003694 in combination with enzalutamide upon confirmed radiographic progression by PCWG3 criteria by independent central review.
Primary Outcome Measures
NameTimeMethod
Cohort A: Radiographic progression-free survival (rPFS) by BICRRandomization up to 30 months

Time from date of randomization to the date of first disease radiographic progression or death for any reason. Radiographic progression disease will be evaluated by RECIST 1.1 and PCWG3.

Secondary Outcome Measures
NameTimeMethod
Cohorts A + B: Radiographic progression-free survival (rPFS) by BICRRandomization up to 30 months

Time from date of randomization to the date of first disease radiographic progression or death for any reason. Radiographic progression disease will be evaluated by RECIST 1.1 and PCWG3

Cohort A: Radiographic progression-free survival (rPFS) by investigator assessmentRandomization up to 30 months

Time from date of randomization to the date of first disease radiographic progression or death for any reason. Radiographic progression disease will be evaluated by RECIST 1.1 and PCWG3.

Cohort A + B: Radiographic progression-free survival (rPFS) by investigator assessmentRandomization up to 30 months

Time from date of randomization to the date of first disease radiographic progression or death for any reason. Radiographic progression disease will be evaluated by RECIST 1.1 and PCWG3.

Cohort A: Progression-free survival (PFS) by investigator assessmentRandomization up to 30 months

Time from date of randomization to the date of first disease radiographic progression, clinical progression, or death for any reason. Radiographic progression of disease will be evaluated by RECIST 1.1 and PCWG3 by investigator assessment. Clinical progression is significant pain increase or clinical deterioration that requires initiating another line of treatment.

Cohort A + B: Progression-free survival (PFS) by investigator assessmentRandomization up to 30 months

Time from date of randomization to the date of first disease radiographic progression, clinical progression, or death for any reason. Radiographic progression of disease will be evaluated by RECIST 1.1 and PCWG3 by investigator assessment. Clinical progression is significant pain increase or clinical deterioration that requires initiating another line of treatment.

Cohort A: Overall survival (OS)Randomization up to 30 months

Time from date of randomization to the date of death from any cause

Cohort A + B: Overall survival (OS)Randomization up to 30 months

Time from date of randomization to the date of death from any cause

Cohort A: PSA50 response rateRandomization up to 30 months

PSA response is a reduction in serum PSA concentration of ≥50% from baseline.

Cohort A + B: PSA50 response rateRandomization up to 30 months

PSA response is a reduction in serum PSA concentration of ≥50% from baseline.

Cohort A: Assess efficacy endpoints for patients enrolled in the USARandomization up to 30 months
Cohort A + B: Assess efficacy endpoints for patients enrolled in the USARandomization up to 30 months
Objective response rate (ORR)Randomization up to 30 months

Proportion of the patients who have either a complete response (CR) or partial response (PR) by RECIST 1.1 criteria who have measurable disease at baseline.

Patient-reported health status and quality of life (QoL) measured by European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30)Screening and Day 1 of every 28-day Cycle up to 30 months

EORTC QLQ-C30: cancer-specific instrument with 30 questions to assess the participant QoL. First 28 questions used to evaluate 5 functional scales (physical, role, cognitive, emotional, social), 3 symptom scales (fatigue, nausea and vomiting, pain) and other single items (dyspnea, appetite loss, insomnia, constipation, diarrhea, financial difficulties). Each question assessed on a 4-point scale (1= not at all, 2= a little, 3= quite a bit, 4= very much); functional scales: higher score = better level of functioning; symptom scale: higher score = more severe symptoms; for single items: higher score= more severe problem. Last 2 questions used to evaluate global health status (GHS)/QoL. Each question was assessed on 7-point scale (1= very poor to 7= excellent). Scores averaged, transformed to 0-100 scale; higher score=better quality of life/better level of functioning.

Patient-reported health status and quality of life (QoL) measured by European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Prostate Module (EORTC QLQ-PR25).Screening and Day 1 of every 28-day Cycle up to 30 months

EORTC QLQ-PR25: prostate cancer specific instrument with 25 questions used in conjunction with EORTC QLQ-C30 to assess the participant QoL. Used to evaluate 5 multi-item scales (urinary, bowel, and hormonal treatment-related symptoms, sexual activity, and sexual functioning) and one single item (problems due to incontinence aid use). Each question assessed on a 4-point scale (1= not at all, 2= a little, 3= quite a bit, 4= very much). Scores averaged, transformed to 0-100 scale; higher score=better quality of life/better level of functioning.

Time to initiation of chemotherapyRandomization up to 30 months

Time from date of randomization to the first dose of chemotherapy.

Time to first skeletal related event (SRE)Randomization up to 30 months

Time from date of randomization to the first SRE such as pathological fracture, surgery/radiotherapy for pain/prevention of fracture, hypercalcemia, and spinal cord compression.

Measure plasma concentrations of ZEN003694 and the active metabolite ZEN003791Cycle 1 Day 1: Pre-dose, 1 hour, 2 hours, and 4 hours post-dose; Cycle 2 Day1: Pre-dose, 1 hour, 2 hours, and 4 hours post-dose

Plasma concentrations of ZEN003694 and the active metabolite ZEN003791 will be measured.

Trial Locations

Locations (31)

Hubei Cancer Hospital

🇨🇳

Wuhan, Hubei, China

California Research Institute

🇺🇸

Los Angeles, California, United States

University of California, San Francisco

🇺🇸

San Francisco, California, United States

Innovative Clinical Research Institute

🇺🇸

Whittier, California, United States

Colorado Urology

🇺🇸

Lakewood, Colorado, United States

D&H Cancer Research Center, LLC

🇺🇸

Margate, Florida, United States

BRCR Global

🇺🇸

Plantation, Florida, United States

Hematology Oncology Clinic

🇺🇸

Baton Rouge, Louisiana, United States

Maryland Oncology Hematology, P.A.

🇺🇸

Columbia, Maryland, United States

University of Michigan Rogel Cancer Center

🇺🇸

Ann Arbor, Michigan, United States

Weill Cornell Medical College - New York Presbyterian Hospital

🇺🇸

New York, New York, United States

Messino Cancer Center

🇺🇸

Asheville, North Carolina, United States

Northwest Cancer Specialists, P.C.

🇺🇸

Portland, Oregon, United States

Urology Associates, P.C.

🇺🇸

Nashville, Tennessee, United States

Texas Oncology - Central South

🇺🇸

Austin, Texas, United States

Virginia Cancer Specialists

🇺🇸

Fairfax, Virginia, United States

Seattle Cancer Care Alliance

🇺🇸

Seattle, Washington, United States

Anhui Provincial Hospital

🇨🇳

Hefei, Anhui, China

Chongqing Cancer Hospital

🇨🇳

Chongqing, Chongqing, China

The First Affiliated Hospital of Xiamen University

🇨🇳

Xiamen, Fujian, China

Henan Cancer Hospital

🇨🇳

Zhengzhou, Henan, China

Tongji Hospital of Tongji Medical College, Huazhong University of Science & Technology

🇨🇳

Wuhan, Hubei, China

Hunan Cancer Hospital

🇨🇳

Changsha, Hunan, China

Nanjing Drum Tower Hospital

🇨🇳

Nanjing, Jiangsu, China

Liaoning Cancer Hospital

🇨🇳

Shenyang, Liaoning, China

The First Affiliated Hospital of Xi'an Jiaotang University

🇨🇳

Xi'an, Shaanxi, China

Fudan University Shanghai Cancer Center

🇨🇳

Shanghai, Shanghai, China

Shanghai Tenth People's Hospital

🇨🇳

Shanghai, Shanghai, China

First Hospital of Shanxi Medical University

🇨🇳

Taiyuan, Shanxi, China

Sichuan Provincial People's Hospital

🇨🇳

Chengdu, Sichuan, China

Zhejiang Provincial People's Hospital

🇨🇳

Hangzhou, Zhejiang, China

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