A Study of Pasritamig Versus Placebo in Late Line Metastatic Castration-resistant Prostate Cancer (mCRPC) (KLK2-comPAS)

A Phase 3 Randomized, Double-blind, Placebo-controlled Study of Pasritamig (JNJ-78278343), a T Cell Redirecting Agent Targeting Human Kallikrein 2, + Best Supportive Care Versus Best Supportive Care for Metastatic Castration-resistant Prostate Cancer

The purpose of this study is to evaluate the overall survival (length of time from the start of study to date of death from any cause) for pasritamig (JNJ-78278343) in combination with best supportive care (BSC) as compared to placebo with BSC in participants with metastatic castration-resistant prostate cancer (mCRPC; a stage of cancer that has spread beyond the prostate gland and is no longer responding to hormone therapies).

Study Overview

• Status: Recruiting
• Conditions: Metastatic Castration-resistant Prostate Neoplasms
• Intervention / Treatment: Biological: Pasritamig; Other: Placebo; Drug: Best Supportive Care (BSC)

• Study Type: Interventional
• Enrollment (Estimated): 663
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Study Contact; Phone Number: 844-434-4210; Email: Participate-In-This-Study1@its.jnj.com

Study Locations

• Australia
  • Heidelberg, Australia, 3084
    • Recruiting
    • Warringal Private Hospital
  • Kurralta Park, Australia, 5037
    • Recruiting
    • Icon Cancer Care
  • Melbourne, Australia, 3000
    • Recruiting
    • Peter MacCallum Cancer Centre
  • Murdoch, Australia, 6150
    • Recruiting
    • Fiona Stanley Hospital
  • Woolloongabba, Australia, 4102
    • Recruiting
    • Princess Alexandra Hospital
• Belgium
  • Bruges, Belgium, 8000
    • Recruiting
    • AZ Sint-Jan
  • Brussels, Belgium, 1200
    • Recruiting
    • Cliniques Universitaires Saint Luc
  • Ghent, Belgium, 9000
    • Recruiting
    • Ghent University Hospital
  • Ghent, Belgium, 9000
    • Recruiting
    • AZ Maria Middelares
  • Kortrijk, Belgium, 8500
    • Recruiting
    • Az Groeninge
  • La Louvière, Belgium, 7100
    • Recruiting
    • Chu Helora Hospital La Louviere Site Jolimont
  • Liège, Belgium, 4000
    • Recruiting
    • CHC MontLegia
  • Ottignies, Belgium, 1340
    • Recruiting
    • Clinique Saint Pierre
  • Wilrijk, Belgium, 2610
    • Recruiting
    • ZAS Augustinus
• Brazil
  • Florianópolis, Brazil, 88034 000
    • Recruiting
    • Centro de Pesquisa e Ensino em Oncologia de Santa Catarina CEPEN
  • Joinville, Brazil, 89201 260
    • Recruiting
    • Instituto Joinvilense de Hematologia e Oncologia Ltda Centro de Hematologia e Oncologia
  • Natal, Brazil, 59062 000
    • Recruiting
    • Liga Norte Riograndense contra o cancer
  • Porto Alegre, Brazil, 90560032
    • Recruiting
    • Associação Hospitalar Moinhos de Vento
  • São Paulo, Brazil, 01509 900
    • Recruiting
    • Fundacao Antonio Prudente A C Camargo Cancer Center
• Canada
  • Alberta
    • Calgary, Alberta, Canada, T2N 5G2
      • Recruiting
      • Arthur J E Child Comprehensive Cancer Centre
  • British Columbia
    • Vancouver, British Columbia, Canada, V5Z 4E6
      • Recruiting
      • BC Cancer Vancouver
  • Ontario
    • Oshawa, Ontario, Canada, L1G2B9
      • Recruiting
      • Lakeridge Health
    • Toronto, Ontario, Canada, M4N 3M5
      • Recruiting
      • Sunnybrook Health Sciences Center
    • Toronto, Ontario, Canada, M5G 2C1
      • Recruiting
      • Princess Margaret Hospital
  • Quebec
    • Québec, Quebec, Canada, G1J 1Z4
      • Recruiting
      • CHU de Quebec Universite Laval
• China
  • Beijing, China, 100034
    • Recruiting
    • Peking University First Hospital
  • Changchun, China, 130021
    • Recruiting
    • The First Bethune Hospital of Jilin University
  • Chengdu, China, 610041
    • Recruiting
    • West China Hospital of Sichuan University
  • Chengdu, China, 500643
    • Recruiting
    • The Third People's Hospital of Chengdu
  • Chongqing, China, 400030
    • Recruiting
    • Chongqing University Cancer Hospital
  • Guangzhou, China, 510060
    • Recruiting
    • Sun Yat Sen University Cancer Center
  • Nanjing, China, 210008
    • Recruiting
    • Nanjing Drum Tower Hospital
  • Nanning, China, 530021
    • Recruiting
    • The First Affiliated Hospital of Guangxi Medical University
  • Nantong, China, 226300
    • Recruiting
    • Nantong Tumor Hospital
  • Ningbo, China, 315010
    • Recruiting
    • The First Affiliated Hospital of Ningbo University
  • Shanghai, China, 200032
    • Recruiting
    • Fudan University Shanghai Cancer Center
  • Tianjin, China, 300211
    • Recruiting
    • The Second Hospital Of Tianjin Medical University
  • Wenzhou, China, 325000
    • Recruiting
    • The First Affiliated Hospital of Wenzhou Medical University
  • Wuhan, China, 430071
    • Recruiting
    • Zhongnan Hospital Wu Han University
  • Xi'an, China, 710061
    • Recruiting
    • The First Affiliated Hospital of Xian Jiaotong University
• France
  • Bordeaux, France, 33000
    • Recruiting
    • Institut Bergonie
  • Brest, France, 29200
    • Recruiting
    • CHRU Brest - Hopital Morvan
  • Dijon, France, 21000
    • Recruiting
    • Centre Georges François Leclerc
  • Lille, France, 59000
    • Recruiting
    • Centre Oscar Lambret
  • Lyon, France, 69008
    • Recruiting
    • Centre Leon Berard
  • Paris, France, 75014
    • Recruiting
    • Hopital Saint Joseph
  • Pierre-Bénite, France, 69495
    • Recruiting
    • CHU Lyon Sud
  • Saint-Herblain, France, 44805
    • Recruiting
    • I.C.O. Rene Gauducheau
  • Strasbourg, France, 672098
    • Recruiting
    • Hopitaux Universitaires de Strasbourg
  • Vandœuvre-lès-Nancy, France, 54519
    • Recruiting
    • Institut de Cancérologie de Lorraine
  • Villejuif, France, 94800
    • Recruiting
    • Gustave Roussy
• Germany
  • Braunschweig, Germany, 38126 DE
    • Recruiting
    • Staedtisches Klinikum Braunschweig
  • Duisburg, Germany, 47169
    • Recruiting
    • Urologicum Duisburg
  • Düsseldorf, Germany, 40225
    • Recruiting
    • Universitaetsklinikum Duesseldorf
  • Essen, Germany, 45147
    • Recruiting
    • Universitaetsklinikum Essen
  • Frankfurt am Main, Germany, 60488
    • Recruiting
    • Krankenhaus NorthWest
  • Hamburg, Germany, 20246
    • Recruiting
    • Martini-Klinik am UKE GmbH
  • Heidelberg, Germany, 69120
    • Recruiting
    • Universitaetsklinikum Heidelberg Nationales Centrum fuer Tumorerkrankungen
  • München, Germany, 81675
    • Recruiting
    • Klinikum rechts der Isar der TU Muenchen
  • Münster, Germany, 48149
    • Recruiting
    • Universitaetsklinikum Muenster
  • Nuremberg, Germany, 90419
    • Recruiting
    • Klinikum Nuernberg Nord
  • Nürtingen, Germany, 72622
    • Recruiting
    • Studienpraxis Urologie Nurtingen
• Italy
  • Foggia, Italy, 71122
    • Recruiting
    • Ospedali Riuniti Foggia
  • Milan, Italy, 20133
    • Recruiting
    • Fondazione IRCCS Istituto Nazionale dei Tumori
  • Naples, Italy, 80131
    • Recruiting
    • Azienda Ospedaliera Universitaria Federico II
  • Padova, Italy, 35128
    • Recruiting
    • IOV IRCCS Padova
  • Palermo, Italy, 90127
    • Recruiting
    • Azienda Di Rilievo Nazionale E Di Alta Specializzazione
  • Roma, Italy, 00168
    • Recruiting
    • Fondazione Policlinico Universitario A Gemelli IRCCS
  • Rozzano, Italy, 20089
    • Recruiting
    • Istituto Clinico Humanitas
  • Torino, Italy, 10126
    • Recruiting
    • A.O.U. Citta della Salute e della Scienza di Torino - Presidio Molinette
• Japan
  • Bunkyō City, Japan, 113 8519
    • Recruiting
    • Institute of Science Tokyo Hospital
  • Fukuoka, Japan, 812 8582
    • Recruiting
    • Kyushu University Hospital
  • Hidaka, Japan, 350 1298
    • Recruiting
    • Saitama Medical University International Medical Center
  • Kanazawa, Japan, 920 8641
    • Recruiting
    • Kanazawa University Hospital
  • Kobe, Japan, 650 0017
    • Recruiting
    • Kobe University Hospital
  • Matsuyama, Japan, 791-0280
    • Recruiting
    • National Hospital Organization Shikoku Cancer Center
  • Meguro Ku, Japan, 152 8902
    • Recruiting
    • National Hospital Organization Tokyo Medical Center
  • Sakura, Japan, 285-8741
    • Recruiting
    • Toho University Sakura Medical Center
  • Yokohama, Japan, 232 0024
    • Recruiting
    • Yokohama City University Medical Center
  • Yokohama, Japan, 236 0004
    • Recruiting
    • Yokohama City University Hospital
  • Yokosuka, Japan, 238 8558
    • Recruiting
    • Yokosuka Kyosai Hospital
• Netherlands
  • Delft, Netherlands, 2625 AD
    • Recruiting
    • Reinier de Graaf Gasthuis
  • Groningen, Netherlands, 9728NT
    • Recruiting
    • Martini Ziekenhuis
  • Hilversum, Netherlands, 1212 VG
    • Recruiting
    • Tergooi
  • Hoofddorp, Netherlands, 2134 TM
    • Recruiting
    • Spaarne Gasthuis
  • Maastricht, Netherlands, 6229 HX
    • Recruiting
    • Maastricht UMC
  • Nijmegen, Netherlands, 6532 SZ
    • Recruiting
    • Canisius-Wilhelmina ZH
  • Rotterdam, Netherlands, 3015 GD
    • Recruiting
    • Erasmus MC
  • Zwolle, Netherlands, 8025 AB
    • Recruiting
    • Isala Kliniek
• Poland
  • Bialystok, Poland, 15 276
    • Recruiting
    • Uniwersytecki Szpital Kliniczny W Bialymstoku
  • Bydgoszcz, Poland, 85 048
    • Recruiting
    • IN VIVO Sp. z o.o
  • Koszalin, Poland, 75-581
    • Recruiting
    • Szpital Wojewodzki im Mikolaja Kopernika w Koszalinie
  • Warsaw, Poland, 02 781
    • Recruiting
    • Narodowy Instytut Onkologii im Marii Sklodowskiej Curie Panstwowy Instytut Badawczy
  • Warsaw, Poland, 04 073
    • Recruiting
    • Szpital Grochowski Im Dr Med Rafala Masztaka Sp Z O O
• Puerto Rico
  • Rio Piedras, Puerto Rico, 00935
    • Recruiting
    • Pan American Center for Oncology Trials LLC
  • San Juan, Puerto Rico, 00917
    • Recruiting
    • Puerto Rico Medical Research Center
• South Korea
  • Daejeon, South Korea, 35015
    • Recruiting
    • Chungnam National University Hospital
  • Goyang-si, South Korea, 10408
    • Recruiting
    • National Cancer Center
  • Hwasungun, South Korea, 58128
    • Recruiting
    • Chonnam National University Hwasun Hospital
  • Seoul, South Korea, 05505
    • Recruiting
    • Asan Medical Center
  • Seoul, South Korea, 06351
    • Recruiting
    • Samsung Medical Center
  • Seoul, South Korea, 03722
    • Recruiting
    • Severance Hospital Yonsei University Health System
  • Seoul, South Korea, 06591
    • Recruiting
    • The Catholic University of Korea Seoul St Marys Hospital
• Spain
  • Barcelona, Spain, 08035
    • Recruiting
    • Hosp Univ Vall D Hebron
  • Jerez de la Frontera, Spain, 11407
    • Recruiting
    • Hosp. de Jerez de La Frontera
  • Madrid, Spain, 28034
    • Recruiting
    • Hosp. Univ. Ramon Y Cajal
  • Madrid, Spain, 28041
    • Recruiting
    • Hosp. Univ. 12 de Octubre
  • Málaga, Spain, 29010
    • Recruiting
    • Hosp Virgen de La Victoria
• Taiwan
  • Kaohsiung City, Taiwan, 833
    • Recruiting
    • Chang Gung Memorial Hospital
  • Taichung, Taiwan, 40705
    • Recruiting
    • Taichung Veterans General Hospital
  • Taichung, Taiwan, 435
    • Recruiting
    • Tungs' Taichung MetroHarbor Hospital
  • Taipei, Taiwan, 100
    • Recruiting
    • National Taiwan University Hospital
  • Taipei, Taiwan, 112
    • Recruiting
    • Taipei Veterans General Hospital
  • Taoyuan, Taiwan, 333
    • Recruiting
    • Linkou Chang Gung Memorial Hospital
• United Kingdom
  • Birmingham, United Kingdom, B15 2TH
    • Recruiting
    • University Hospitals Birmingham NHS Foundation Trust
  • London, United Kingdom, WC1E 6BT
    • Recruiting
    • University College London Hospitals
  • Manchester, United Kingdom, M20 4BX
    • Recruiting
    • The Christie NHS Foundation Trust Christie Hospital
  • Sutton, United Kingdom, SM2 5PT
    • Recruiting
    • Royal Marsden Hospital (Sutton)
• United States
  • California
    • La Jolla, California, United States, 92093
      • Recruiting
      • University of California at San Diego
    • Los Angeles, California, United States, 90095
      • Recruiting
      • Ronald Reagan UCLA Medical Center
  • Colorado
    • Aurora, Colorado, United States, 80045
      • Recruiting
      • University of Colorado Cancer Center
    • Aurora, Colorado, United States, 80012
      • Recruiting
      • Rocky Mountain Cancer Centers
    • Lakewood, Colorado, United States, 80228
      • Recruiting
      • Colorado Clinical Research
  • Connecticut
    • Hartford, Connecticut, United States, 06102
      • Recruiting
      • Hartford Hospital
  • District of Columbia
    • Washington D.C., District of Columbia, United States, 20016
      • Recruiting
      • Johns Hopkins Office of Capital Region Research - Sibley Memorial Hospital
  • Florida
    • Bay Pines, Florida, United States, 33744
      • Recruiting
      • Bay Pines VA Healthcare System
    • Fort Myers, Florida, United States, 33901
      • Recruiting
      • Florida Cancer Specialists & Research Institute
    • Tampa, Florida, United States, 33612
      • Recruiting
      • Moffitt Cancer Center
  • Iowa
    • Iowa City, Iowa, United States, 52242
      • Recruiting
      • University of Iowa Hospital and Clinics
    • Waukee, Iowa, United States, 50263
      • Recruiting
      • Mission Cancer Blood
  • Louisiana
    • Metairie, Louisiana, United States, 70006
      • Recruiting
      • East Jefferson General Hospital
  • Maryland
    • Baltimore, Maryland, United States, 21287
      • Recruiting
      • Johns Hopkins University
  • Massachusetts
    • Boston, Massachusetts, United States, 02115
      • Recruiting
      • Dana Farber Cancer Institute
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • Recruiting
      • University of Michigan Health System
    • Detroit, Michigan, United States, 48202
      • Recruiting
      • Henry Ford Cancer Detroit
  • Minnesota
    • Minneapolis, Minnesota, United States, 55455
      • Recruiting
      • University of Minnesota Medical Center
  • Nebraska
    • Omaha, Nebraska, United States, 68130
      • Recruiting
      • XCancer Omaha / Urology Cancer Center
  • New York
    • Brooklyn, New York, United States, 11220
      • Recruiting
      • NYU Langone Hospitals
    • Mineola, New York, United States, 11501
      • Recruiting
      • NYU Langone Hospital Long Island
    • New York, New York, United States, 10032
      • Recruiting
      • Columbia University Medical Center
    • New York, New York, United States, 10016
      • Recruiting
      • NYU Langone Health Laura and Isaac Perlmutter Cancer Center
  • Ohio
    • Cincinnati, Ohio, United States, 45219
      • Recruiting
      • University Of Cincinnati
    • Cleveland, Ohio, United States, 44106
      • Recruiting
      • University Hospital of Cleveland
  • Oregon
    • Portland, Oregon, United States, 97239
      • Recruiting
      • VA Portland Health Care System
    • Portland, Oregon, United States, 97227
      • Recruiting
      • Compass Oncology
    • Springfield, Oregon, United States, 97477
      • Recruiting
      • Oregon Urology Institute
  • Pennsylvania
    • Bala-Cynwyd, Pennsylvania, United States, 19004
      • Recruiting
      • MidLantic Urology
    • Lancaster, Pennsylvania, United States, 17601
      • Recruiting
      • Keystone Urology Specialists
    • Philadelphia, Pennsylvania, United States, 19104
      • Recruiting
      • Penn Medicine Abramson Cancer Center
    • Pittsburgh, Pennsylvania, United States, 15232
      • Recruiting
      • UPMC Cancer Centers
  • South Carolina
    • Charleston, South Carolina, United States, 29401
      • Recruiting
      • Ralph H Johnson Veterans Hospital
    • Greer, South Carolina, United States, 29650
      • Recruiting
      • Gibbs Cancer Center and Research Institute Pelham
    • Myrtle Beach, South Carolina, United States, 29572
      • Recruiting
      • Carolina Urologic Research Center
    • Spartanburg, South Carolina, United States, 29303
      • Recruiting
      • Gibbs Cancer Center
  • Tennessee
    • Chattanooga, Tennessee, United States, 37404
      • Recruiting
      • Tennessee Oncology - Chattanooga
    • Nashville, Tennessee, United States, 37203
      • Recruiting
      • Tennessee Oncology Nashville
  • Texas
    • Dallas, Texas, United States, 75231
      • Recruiting
      • Urology Clinics of North Texas
    • Dallas, Texas, United States, 75390
      • Recruiting
      • UT Southwestern Medical Center
    • Houston, Texas, United States, 77030
      • Recruiting
      • MD Anderson Cancer Center
    • Houston, Texas, United States, 77030
      • Recruiting
      • Michael E DeBakey VA Medical Center
    • Wichita Falls, Texas, United States, 76310
      • Recruiting
      • Texas Oncology West Texas
  • Utah
    • Salt Lake City, Utah, United States, 84106
      • Recruiting
      • Utah Cancer Specialists
  • Virginia
    • Fairfax, Virginia, United States, 22031
      • Recruiting
      • Virginia Cancer Specialists
    • Norfolk, Virginia, United States, 23502
      • Recruiting
      • Virginia Oncology Associates
    • Roanoke, Virginia, United States, 24014
      • Recruiting
      • Blue Ridge Cancer Care
  • Washington
    • Seattle, Washington, United States, 98195
      • Recruiting
      • University of Washington
    • Seattle, Washington, United States, 98109
      • Recruiting
      • Fred Hutchinson Cancer Research Center
    • Seattle, Washington, United States, 98108
      • Recruiting
      • VA Puget Sound Healthcare System

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria

• Histologically confirmed adenocarcinoma of the prostate
• Metastatic castration-resistant prostate cancer (mCRPC): Disease that is metastatic either to bone, any lymph node, or both without clear evidence of other metastatic sites at the time of screening by conventional imaging with computed tomography (CT) or magnetic resonance imaging (MRI) (chest, abdomen, and pelvis) and 99m^Tc bone scan
• PSA greater than or equal to (>=) 2 nanogram per milliliter (ng/mL) at screening
• In the opinion of the investigator, the next best treatment option is a clinical trial
• Participants should have had all life-prolonging therapies for which they are clinically eligible in the opinion of the investigator and to which they have access. Prior therapies could have been given in any disease setting (not limited to mCRPC). In particular, prior treatment specifications include receipt of the following:

Androgen-receptor pathway inhibitor (ARPI): Must have progressed on at least 1 ARPI and unlikely to benefit from retreatment with another ARPI

Taxanes: Should have received at least 2 previous taxane-based regimens. If a participant has received only 1 taxane regimen, the participant is eligible if:

1. Cabazitaxel is not available
2. The participant's physician deems the participant unsuitable to receive a second taxane regimen due to toxicity risk or prior intolerance Note: a taxane-based regimen consists of at least 2 cycles of a taxane (either as a single agent or in combination with other therapies) administered within the same 2-month period. Participants who cannot continue taxane therapy because of a documented Grade>=3 taxane related IRR are eligible for enrollment, even if they received fewer than 2 prior cycles of taxane treatment

Radioligand therapy: Should have been previously treated with at least 1 dose of Prostate-specific membrane antigen (PSMA)-targeted lutetium radioligand therapy (eg, lutetium Lu-177 vipivotide tetraxetan), unless one of the following applies:

1. PSMA-targeted lutetium radioligand therapy is unavailable, not accessible, or not clinically indicated.
2. The participant's physician deems the participant unsuitable to receive PSMA-targeted lutetium radioligand therapy.

Polyadenosine diphosphate-ribose polymerase inhibitors (PARPi): Should have been previously treated with PARPi, if the participant has a known germline or somatic BRCA mutation and treatment is available

• Prior orchiectomy or medical castration (receiving ongoing ADT with a GnRH analog [agonist or antagonist]) prior to the first dose of study treatment and must continue this therapy throughout the treatment phase
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
• Participants are eligible if they have the following values:

A) eGFR >= 30 milliliters per minute (mL/min) B) Alanine Aminotransferase (ALT) and Aspartate Aminotransferase (AST) less than or equal to (<=) 5 times the Upper Limit of Normal (ULN) C) Serum total bilirubin <= 3 times ULN D) Absolute neutrophil count (ANC) >= 1.0x10^9/per liter (L) E) Hemoglobin >= 8.0 grams per deciliter (g/dL) F) Platelet count >= 75x10^9/L

Exclusion Criteria

• Venous thromboembolic events within 1 month prior to the first dose of study treatment; uncomplicated (Grade <= 2) deep vein thrombosis is not exclusionary
• Active autoimmune disease within the past 12 months that requires systemic immunosuppressive medications (eg, chronic corticosteroid, methotrexate, or tacrolimus)
• Participants with Grade 1 or higher fever (>=38ºC) or active infection requiring systemic treatment within 7 days prior to randomization are ineligible. Participants must be afebrile (<38ºC) at the time of study treatment dosing unless approved by medical monitor
• Clinically significant pulmonary compromise, particularly a requirement for supplemental oxygen use (>2 liters per minute (L/min) by nasal cannula) to maintain adequate oxygenation
• Prior or concurrent second malignancy (other than the disease under study) for which natural history or treatment could likely interfere with any study endpoints of safety or the efficacy of the study treatment(s)
• Any of the following within 6 months prior to first dose of study treatment:

A) Myocardial infarction B) Severe or unstable angina C) Clinically significant ventricular arrhythmias D) Congestive heart failure (New York Heart Association class II to IV) E) Transient ischemic attack F) Cerebrovascular accident

- Prior treatment with any CD3-directed therapy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Pasritamig Plus Best Supportive Care (BSC); Participants will receive the step-up doses of pasritamig intravenously (IV) on Cycle 1 Day 1 (C1D1) and C1D8, and target dose of pasritamig IV on C1D15. From C2D1 onwards participants will receive pasritamig target dose IV every 6 weeks. All Cycles are 6 weeks, except for Cycle 1 which is 8 weeks. Participants will receive study treatment until confirmed progressive disease, death, intolerable toxicity, withdrawal of consent, or end of the study, whichever occurs first. All participants may receive BSC (defined as palliative external beam radiation, low dose steroids, pain medication, bone sparing agents, and needed palliative procedures) at the discretion of the physician.	Biological: Pasritamig; Pasritamig will be administrated through IV infusion.; Other Names: JNJ-78278343; Drug: Best Supportive Care (BSC); BSC will be administered at the discretion of the treating physician.
Placebo Comparator: Placebo Plus BSC; Participants will receive the step-up doses of placebo IV on C1D1 and C1D8, and target dose of placebo on C1D15. From C2D1 onwards, participants will receive placebo target dose IV every 6 weeks. All Cycles are 6 weeks, except for Cycle 1 which is 8 weeks. Participants will receive study treatment until confirmed progressive disease, death, intolerable toxicity, withdrawal of consent, or end of the study, whichever occurs first. All participants may receive BSC at the discretion of the physician.	Other: Placebo; Placebo will be administrated through IV infusion.; Drug: Best Supportive Care (BSC); BSC will be administered at the discretion of the treating physician.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Survival (OS)	OS is defined as the time from randomization to date of death due to any cause.	Up to 2 years and 8 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Radiographic Progression-free Survival (rPFS)	rPFS assessed by investigator defined as the time from the date of randomization until the date of radiographic disease progression (based on response evaluation criteria in solid tumors [RECIST] v1.1 and prostate cancer working group 3 [PCWG3] criteria) or death, whichever comes first.	Up to 2 years and 8 months
Time to Symptomatic Progression	Time to symptomatic progression is defined as time from the date of randomization to the date of any of the following (whichever occurs first): (a) the use of external beam radiation therapy to relieve cancer-related symptoms; (b) the need for tumor-related orthopedic surgical intervention; (c) other cancer-related procedures; (d) cancer-related morbid events; (e) initiation of a new systemic anti-cancer therapy because of cancer symptoms.	Up to 2 years and 8 months
Time to Skeletal-Related Event	Time to skeletal-related event is defined as the time from the date of randomization to the date of first occurrence of any of the following (whichever occurs first): (a) the use of external beam radiation for skeletal or pelvic symptoms; b) the need for tumor-related orthopedic surgical intervention; (c) the occurrence of new bone fractures (cancer-related); (d) the occurrence of tumor-related spinal cord compression.	Up to 2 years and 8 months
Progression-Free Survival (PFS)	PFS is defined as the date of randomization to the date of first evidence of radiographic progression, clinical progression, or death from any cause, whichever occurs first.	Up to 2 years and 8 months
Time to Prostate Specific Antigen (PSA) Progression	Time to PSA progression, defined as the time from randomization to the first date of documented PSA progression per PCWG3 criteria. PSA progression is defined as: after a decline from baseline, PSA increases >= 25 percentage (%) and >= 2 nanograms per milliliter (ng/mL) above the nadir, confirmed by a second value >= 3 weeks later (that is, a confirmed rising trend), or If there is no decline from baseline, PSA increases >= 25 % and >= 2 ng/mL from baseline after 12 weeks.	Up to 2 years and 8 months
Time to Pain Progression (TTPP) as Assessed by the Brief Pain Inventory-Short Form (BPI-SF) Item 3 Worst Pain in 24 Hours	TTPP is defined as the time from the date of randomization to the date of the first observation of pain progression. Pain progression is defined as an increase of at least 2 points from baseline in the BPI-SF worst pain intensity (item 3) observed at 2 consecutive evaluations >= 3 weeks apart. BPI-SF is an 11-item questionnaire, designed to assess severity and impact of pain on daily functions. Total score range from 0 to 10 with 0 representing "no pain" and 10 representing" pain as bad as you can imagine".	Up to 2 years and 8 months
Time to Deterioration in Fatigue as Assessed by the European Organisation For Research And Treatment of Cancer Quality of Life Questionnaire-Core-30 (EORTC QLQ-C30) Fatigue Scale Score	Time to deterioration is defined as the time from randomization to the date of the first observation of deterioration in Fatigue. Deterioration in Fatigue is defined as an increase of 10 points on the EORTC QLQ-C30 FA scale observed at 2 consecutive evaluations >= 3 weeks apart. The EORTC QLQ-C30 is a widely used tool for assessing the quality of life of cancer patients in clinical trials. 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". Each subscale of the EORTC QLQ-C30 is scored on a range from 0 to 100. Higher scores indicate worse symptoms or problems.	Up to 2 years and 8 months
Number of Participants with Adverse Events (AEs)	An AE is any untoward medical occurrence in a participant participating in a clinical study that does not necessarily have a causal relationship with the pharmaceutical/biological agent under study.	Up to 2 years and 8 months
Number of Participants with Abnormalities in Clinical Laboratory Assessments	Participants with abnormalities in clinical laboratory parameters (hematology, clinical chemistry etc.) will be assessed.	Up to 2 years and 8 months

Collaborators and Investigators

• Sponsor: Janssen Research & Development, LLC
• Investigators: Study Director: Janssen Research & Development, LLC Clinical Trial, Janssen Research & Development, LLC

Study record dates

Study Major Dates

• Study Start (Actual): September 2, 2025
• Primary Completion (Estimated): December 29, 2027
• Study Completion (Estimated): December 29, 2027

Study Registration Dates

• First Submitted: September 4, 2025
• First Submitted That Met QC Criteria: September 4, 2025
• First Posted (Actual): September 10, 2025

Study Record Updates

• Last Update Posted (Actual): June 5, 2026
• Last Update Submitted That Met QC Criteria: June 4, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Substandard Drugs; Pharmaceutical Preparations; Counterfeit Drugs
• Other Study ID Numbers: 78278343PCR3001 (Janssen Research & Development, LLC); 2025-520927-26-00 (Registry Identifier: EUCT number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The data sharing policy of Johnson & Johnson Innovative Medicine is available at innovativemedicine.jnj.com/our-innovation/clinical-trials/transparency. As noted on this site, requests for access to the study data can be submitted through Yale Open Data Access (YODA) Project site at yoda.yale.edu

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No