A Study of Pasritamig With Docetaxel Versus Docetaxel in Participants With Metastatic Castration-Resistant Prostate Cancer

Summary

The purpose of this study is to find out whether treatment with pasritamig and docetaxel prolongs radiographic progression free survival (rPFS) (the length of time from start of treatment until disease worsens as determined by scans or death due to any cause) when compared to treatment with docetaxel in participants with metastatic castrate-resistant prostate cancer (mCRPC; a cancer of prostate, a male reproductive gland found below the bladder, that grows despite low levels of male hormones).

Eligibility

Study design

Outcome measures

1. Primary outcome

   Radiographic Progression-Free Survival (rPFS) by computed tomography (CT)/magnetic resonance imaging (MRI) or bone scan Assessed by Blinded Independent Central Review (BICR)

   rPFS by CT/MRI or bone scan is assessed by BICR and is defined as the time from the date of randomization to the first date of radiographic disease progression, or death due to any cause, whichever occurs first.

   Time frame Up to approximately 1 years 10 months

2. Secondary outcome

   Overall Survival (OS)

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

   Time frame Up to approximately 4 years 5 months

3. Secondary outcome

   Time to Symptomatic Progression (TSP)

   TSP is defined as the time from the date of randomization to the date of the first occurrence of any of the following: the use of external beam radiation to relieve cancer-related symptoms, the need for tumor-related surgical intervention, other cancer-related procedures, cancer-related morbid events, and initiation of a new systemic anticancer therapy because of cancer symptoms.

   Time frame Up to approximately 4 years 5 months

4. Secondary outcome

   Time to Subsequent Therapy (TST)

   TST is defined as time from randomization to the initiation of any subsequent systemic anticancer therapy for prostate cancer

   Time frame Up to approximately 4 years 5 months

5. Secondary outcome

   Time to Skeletal-Related Event (TSRE)

   TSRE is defined as the time from the date of randomization to the date of first occurrence of any of the following (whichever occurs first): the use of external beam radiation therapy to relieve skeletal symptoms, the need for tumor-related orthopedic surgical intervention, the occurrence of new bone fractures (cancer-related; vertebral or non-vertebral) or the occurrence of tumor-related spinal cord compression.

   Time frame Up to approximately 4 years 5 months

6. Secondary outcome

   Objective Response Rate (ORR)

   ORR is defined as the proportion of participants who have measurable disease at baseline and have complete response (CR) or partial response (PR) or better by objective radiographic disease evaluation per response evaluation criteria in solid tumors (RECIST) version.1.1 response criteria and no bone progression as per prostate cancer working group 3 (PCWG3) as determined by the BICR.

   Time frame Up to approximately 4 years 5 months

7. Secondary outcome

   Duration of Response (DOR)

   DOR will be calculated among responders (PR or better) from the date of initial documentation of a response (PR or better) to the date of first documented evidence of progressive disease, as defined in the PCWG3 or RECIST version 1.1 response criteria, or death due to any cause, whichever occurs first.

   Time frame Up to approximately 4 years 5 months

8. Secondary outcome

   Time to Prostate-Specific Antigen (PSA) Progression

   Time to PSA progression is defined as the time from randomization to the first date of documented PSA progression per prostate cancer working group 3 (PCWG3) criteria. PSA progression is defined as: (1) After a decline from baseline, PSA increases greater than or equal to (\>=) 25% and \>=2 nanogram per milliliter (ng/mL) above the nadir, confirmed by a second value \>=3 weeks later (that is, a confirmed rising trend), or (2) If there is no decline from baseline, PSA increases \>=25% and \>=2 ng/mL from baseline after 12 weeks

   Time frame Up to approximately 4 years 5 months

9. Secondary outcome

   Proportion of Participants Who Achieved Prostate-Specific Antigen (PSA) 50 Response

   PSA-50 response is defined as the proportion of participants with a reduction in blood concentration of PSA (ng/mL) to 50% from baseline, confirmed by a second value, at least 3 weeks apart.

   Time frame Up to approximately 4 years 5 months

10. Secondary outcome

    Proportion of Participants Who Achieved Prostate-Specific Antigen (PSA) 90 Response

    PSA-90 response is defined as the proportion of participants with a reduction in blood concentration of PSA (ng/mL) to 90% from baseline, confirmed by a second value, at least 3 weeks apart.

    Time frame Up to approximately 4 years 5 months

11. Secondary outcome

    Duration of PSA Response

    Duration of a PSA response is the time taken to achieve a PSA response that is decrease in PSA from baseline by \>= 50%.

    Time frame Baseline and up to approximately 4 years 5 months

12. Secondary outcome

    Progression Free Survival After Subsequent Therapy (PFS2)

    PFS2 is defined as the time from randomization to the date of progression (radiographic, clinical, or PSA progression) on the first subsequent anti-cancer (second progression), or death from any cause, whichever comes first.

    Time frame Up to approximately 4 years 5 months

13. Secondary outcome

    Number of Participants with Adverse Events (AEs) and Serious Adverse Events (SAEs) by Severity

    An AE is any untoward medical occurrence in a participant administered a pharmaceutical (investigational or non investigational) product. An AE does not necessarily have a causal relationship with the treatment. An SAE: results in death, is life-threatening, requires inpatient hospitalization or prolonging hospitalization, results in disability, is a congenital birth defect, is a suspected transmission of any infectious agent via a medicinal product, is indicating suicidal ideation, is medically important. Severity of AEs will be graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) v5.0. by using standard grades as follows: Grade 1: Mild; asymptomatic or mild symptoms; Grade 2: Moderate; minimal, local or noninvasive intervention indicated; Grade 3: Severe but not immediately life threatening; hospitalization or prolongation of hospitalization indicated; Grade 4: Life-threatening consequences; and Grade 5: Death related to AE.

    Time frame Up to approximately 4 years 5 months

14. Secondary outcome

    Number of Participants With Clinical Laboratory Abnormalities

    Participants with laboratory abnormalities (hematology, serum chemistry, coagulation, and tumor markers) will be reported.

    Time frame Up to approximately 4 years 5 months

15. Secondary outcome

    Change from Baseline in Health Related Quality of Life (HRQoL) as Assessed by Brief Pain Inventory-Short Form (BPI-SF)

    The BPI-SF was developed to measure both intensity or severity of pain and pain interference with daily life dimensions. It measures pain intensity via 4 questions, that is, "pain at its worst in the last 24 hours", "pain at its least in the last 24 hours", "pain on the average", and "pain you have right now". The BPI-SF assesses how much pain has interfered with the following 7 activities: general activity, mood, walking ability, normal work, relations with other people, sleep, and enjoyment of life. Higher score indicates more pain.

    Time frame Baseline up to approximately 4 years 5 months

16. Secondary outcome

    Change from Baseline in HRQoL as Assessed by European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Cancer Module (EORTC QLQ-C30) Scale Score

    The EORTC QLQ-C30 - Version 3 is a self-administered, 30-item questionnaire measuring the health-related quality of life of participants with cancer. EORTC QLQ-C30 includes 5 functional scales (physical, role, cognitive, emotional, and social), 3 symptom scales (fatigue, pain, and nausea and vomiting), a global health status / quality of life scale, and 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties). Responses to items 1-28 are rated on a 4-point Likert response scale ranging from 1 "Not at all" to 4 "Very much". Two global health status items are rated on a 7-point numeric rating scale from 1 "Very Poor" to 7 "Excellent". A high score for a functional scale represents a high level of functioning, whereas a high score for a symptom scale/single item represents a high level of symptom.

    Time frame Baseline up to approximately 4 years 5 months

17. Secondary outcome

    Change from Baseline in HRQoL as Assessed by EORTC Quality of Life Questionnaire-Prostate (EORTC QLQ-PR25) Scale Score

    The EORTC QLQ-PR25 is a self-completed instrument was specifically designed for prostate cancer patients and includes 25 items that cover 6 dimensions: (1) PR URI (urinary symptoms, 8 items), (2) PR BOW (bowel symptoms, 4 items), (3) PR HTR (hormonal treatment-related symptoms, 6 items), (4) PR AID (incontinence aid, 1 item), (5) PR SAC (sexually active, 2 items); and (6) PR SFU (sexual function, 4 items). Higher scores on symptom domains (for example., urinary, bowel, etc.) indicate greater symptom burden and higher scores on function domains (for example, Sexual Function) indicate better functioning.

    Time frame Baseline up to approximately 4 years 5 months

18. Secondary outcome

    Change from Baseline in HRQoL as Assessed by European Quality of Life Visual Analog Scale (EQ-5D VAS) Score

    The EQ-5D descriptive system comprises 5 items across the following 5 dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. The EQ-5D includes a visual analog scale (EQ-VAS) that has endpoints labeled "best imaginable health state" and "worst imaginable health state" anchored at 100 and 0, respectively. Here, higher score indicates better quality of life.

    Time frame Baseline up to approximately 4 years 5 months

19. Secondary outcome

    Time to Sustained Worsening of Pain as Assessed by BPI-SF

    Time to sustained worsening of pain will be reported using BPI-SF. The BPI-SF was developed to measure both intensity or severity of pain and pain interference with daily life dimensions. It measures pain intensity via 4 questions, that is, "pain at its worst in the last 24 hours", "pain at its least in the last 24 hours", "pain on the average", and "pain you have right now". The BPI-SF assesses how much pain has interfered with the following 7 activities: general activity, mood, walking ability, normal work, relations with other people, sleep, and enjoyment of life. Higher score indicates more pain.

    Time frame Up to approximately 4 years 5 months

20. Secondary outcome

    Treatment Side Effect as Assessed by EORTC IL46 Score

    The EORTC IL46 is a single question that assesses bother (burden) of treatment. It is rated on a scale from 1 to 4, ranging from "not at all" to "very much".

    Time frame Up to approximately 4 years 5 months

21. Secondary outcome

    European Quality of Life 5 Dimensions 5 Level Version (EQ-5D-5L) Scale Score

    The EQ-5D descriptive system comprises 5 items across the following 5 dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. The EQ-5D-5L uses a 5-point Likert response scale ranging from "No problems" to "Extreme problems". Here, higher score indicates better quality of life.

    Time frame Up to approximately 4 years 5 months

Dates

Actual means the event happened. Estimated means the sponsor expects it. The two mean different things.

Locations

152 sites are recruiting

102 further sites are listed in the registry record.

Study documents

No documents are linked in this registry record.

Changes over time

1. August 28, 2026

   Site added

   2 sites added (152 total)

   150 → 152

2. July 30, 2026

   Site added

   14 sites added (150 total)

   136 → 150