Updated May 2026 · ClinicalTrials.gov

RECRUITINGPhase 1INTERVENTIONAL

A Study of JNJ-87189401 Plus JNJ-78278343 for Advanced Prostate Cancer

A Phase 1 Study of JNJ-87189401 (PSMA-CD28 Bispecific Antibody) Combined With JNJ-78278343 (KLK2-CD3 Bispecific Antibody) for Advanced Prostate Cancer

A Study of JNJ-87189401 Plus JNJ-78278343 for Advanced Prostate Cancer (NCT06095089) is a Phase 1 interventional studying Advanced Prostate Cancer, sponsored by Janssen Research & Development, LLC. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

What Stage of Research Is This?

Phase 1 trials test a new treatment for the first time in humans, focusing on safety, dosing, and how the body processes the drug. For Advanced Prostate Cancer, a Phase 1 study typically enrolls a small number of participants — often healthy volunteers or patients who have exhausted standard treatment options. Phase 1 results determine whether a treatment moves into larger Phase 2 efficacy studies.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 250 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Advanced Prostate Cancer subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.

Who May Be Eligible (Plain English)

Who May Qualify: - diagnosed by tissue sample (biopsy-confirmed) adenocarcinoma of the prostate. Adenocarcinoma with small cell or neuroendocrine (NE) features is permitted. However, small cell carcinoma, carcinoid tumor, mixed NE carcinoma, or large cell NE carcinoma is disallowed - Measurable or evaluable disease per PCWG3 criteria - Part 1, Part 2A and Part 2B: Prior orchiectomy or medical castration; participants who have not undergone orchiectomy, must be receiving ongoing androgen deprivation therapy with a gonadotropin releasing hormone (GnRH) analog (agonist or antagonist), prior to the first dose of study drug and must continue this therapy throughout the treatment phase - Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 Who Should NOT Join This Trial: - Active autoimmune conditions (where your immune system attacks your own body) within the 12 months prior to signing consent that requires systemic immunosuppressive medications (example, chronic corticosteroids, methotrexate, or tacrolimus) - Any of the following within 6 months prior to signature of willing to sign a consent form: a. myocardial infarction, b. severe or unstable angina, c. clinically significant ventricular arrhythmias, d. congestive heart failure (New York Heart Association \[NYHA\] class II to IV), e. transient ischemic attack, and f. Cerebrovascular accident Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: * Histologically confirmed adenocarcinoma of the prostate. Adenocarcinoma with small cell or neuroendocrine (NE) features is permitted. However, small cell carcinoma, carcinoid tumor, mixed NE carcinoma, or large cell NE carcinoma is disallowed * Measurable or evaluable disease per PCWG3 criteria * Part 1, Part 2A and Part 2B: Prior orchiectomy or medical castration; participants who have not undergone orchiectomy, must be receiving ongoing androgen deprivation therapy with a gonadotropin releasing hormone (GnRH) analog (agonist or antagonist), prior to the first dose of study drug and must continue this therapy throughout the treatment phase * Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 Exclusion Criteria: * Active autoimmune disease within the 12 months prior to signing consent that requires systemic immunosuppressive medications (example, chronic corticosteroids, methotrexate, or tacrolimus) * Any of the following within 6 months prior to signature of informed consent: a. myocardial infarction, b. severe or unstable angina, c. clinically significant ventricular arrhythmias, d. congestive heart failure (New York Heart Association \[NYHA\] class II to IV), e. transient ischemic attack, and f. Cerebrovascular accident

Treatments Being Tested

DRUG

JNJ-78278343

JNJ-78278343 will be administered.

DRUG

JNJ-87189401

JNJ-87189401 will be administered.

Locations (6)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

University of Colorado Anschutz Medical Campus

Aurora, Colorado, United States

Herbert Irving Comprehensive Cancer Center Columbia University Medical Center

New York, New York, United States

Tennessee Oncology

Nashville, Tennessee, United States

South Texas Accelerated Research Therapeutics, LLC (START)

San Antonio, Texas, United States

Centre Leon Berard

Lyon, France

Institut Gustave Roussy

Villejuif, France

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT06095089), the sponsor (Janssen Research & Development, LLC), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT06095089 clinical trial studying?

The purpose of the study is to determine the recommended regimen for Phase 2 (RP2Rs) of combination of JNJ-87189401 with JNJ-78278343 (Part 1: dose escalation) and further evaluate the safety at RP2Rs (Part 2: dose expansion) in participants with advanced prostate cancer. The full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.

Who can participate in NCT06095089?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT06095089?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT06095089. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT06095089. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.