New hope for japanese men with tough prostate cancer?
NCT ID NCT06104449
First seen Jun 27, 2026 · Last updated Jun 27, 2026
Summary
This early-phase study tested a new drug, opevesostat (MK-5684), in 7 Japanese men with a type of advanced prostate cancer that no longer responds to standard hormone therapy. The main goals were to check the drug's safety and how the body processes it. This is a first step to see if the drug might help control the disease.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Phase 1
The first testing in people. Mainly checks safety and dose, usually in a small group.
- Participants
-
7 people
The number who actually took part.
- Started
-
Nov 2023
- Finished
-
Apr 2026
- Lead sponsor
-
A company
The lead sponsor is a pharmaceutical, biotech, or medical-device company.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
18 years and older
- Sex
-
Male participants only
- Healthy volunteers
-
Not accepted
This study is not open to healthy volunteers. The entry requirements below say who it is open to.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
The main inclusion and exclusion criteria include but are not limited to the following: Inclusion Criteria: * Has histologically- or cytologically-confirmed adenocarcinoma of the prostate without small cell histology * Has current evidence of metastatic disease documented by either bone lesions on bone scan and/or soft tissue disease by computed tomography/magnetic resonance imaging (CT/MRI) * Has ongoing androgen deprivation with serum testosterone \<50 ng/dL (\<1.7 nmol/L) * Participants receiving bone anti-resorptive therapy (including, but not limited to bisphosphonate or denosumab) must have been on stable doses for ≥4 weeks prior to the start of study intervention. * Has progressed on or after treatment with at least 1 line of NHAs in metastatic hormone-sensitive prostate cancer (mHSPC) or in castration-resistant prostate cancer (CRPC) for a minimum of 12 weeks (e.g. abiraterone, enzalutamide, darolutamide, apalutamide), and with at least 1 line of taxane-based chemotherapy in mHSPC or in CRPC, or ineligibility for chemotherapy * Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 within 10 days prior to allocation * If capable of producing sperm, participant must agree to the following during the study treatment period and for at least 7 days after the last dose of opevesostat: Refrain from donating sperm, plus EITHER be abstinent OR must agree to use male condom. Exclusion Criteria: * Has a history of pituitary dysfunction * Has brain metastases * History of a second malignancy, unless potentially curative treatment has been completed with no evidence of malignancy for 3 years * Has an active or uncontrolled autoimmune disease that has required systemic treatment in past 2 years (ie, with use of disease modifying agents, corticosteroids, or immunosuppressive drugs) * Has an active infection or other medical condition that would make corticosteroid contraindicated * Has serious persistent infection within 2 weeks prior to the start of the study intervention * Participants on an unstable dose of thyroid hormone therapy within 6 months prior to the start of the study intervention * Has poorly controlled diabetes mellitus * Hypotension: systolic blood pressure (BP) \< 110 mmHg, or uncontrolled hypertension: systolic BP ≥ 160 mmHg or diastolic BP ≥ 95 mmHg, in 2 out of 3 recordings with optimized antihypertensive therapy * Has active or unstable cardio/cerebro-vascular disease, including thromboembolic event * Is unable to swallow orally administered medication or known gastrointestinal (GI) disease or GI procedure that may interfere with absorption of study intervention * Has undergone major surgery including local prostate intervention (excluding prostate biopsy) within 28 days prior to the start of the study intervention and not adequately recovered from the toxicities and/or complications * Has received aldosterone antagonist (e.g. spironolactone, eplerenone) and phenytoin within 4 weeks prior to the start of the study intervention * Has received radiotherapy within 4 weeks prior to the start of the study intervention, or radiation related toxicities, requiring corticosteroids * Has received chemotherapy within the last 4 weeks (2 weeks for oral or weekly chemotherapy; 6 weeks for nitrosoureas and mitomycin C) prior to the start of the study intervention * Has received prior enzalutamide and apalutamide within 3 weeks, or abiraterone and darolutamide within 2 weeks prior to the start of the study intervention * Systemic use of the following medications within 2 weeks prior to the start of study intervention: strong cytochrome P450 (CYP)3A4 inducers: e.g., carbamazepine, rifampicin, phenobarbital, phenytoin, St John's Wort) and strong CYP3A4 inhibitors: e.g., itraconazole, ketoconazole, posaconazole, voriconazole, clarithromycin, telithromycin, grapefruit juice * Received a live or live-attenuated vaccine within 30 days before the first dose of study intervention. Administration of killed vaccines are allowed. * Has used herbal products that may have hormonal anti-prostate cancer activity and/or are known to decrease PSA levels (eg, saw palmetto) within 4 weeks prior to the start of the study intervention * Has received treatment with 5-α reductase inhibitors (eg, finasteride or dutasteride), estrogens, and/or cyproterone within 4 weeks prior to the start of the study intervention * Has received an investigational agent or has used an investigational device within 4 weeks prior to study intervention administration * History of human immunodeficiency virus (HIV) infection * Has a history of Hepatitis B or active Hepatitis C virus * Has a "superscan" bone scan * Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of immunosuppressive therapy within 7 days prior to the start of the study intervention
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for Metastatic castration resistant prostate cancer are added.
Genom att skicka in godkänner du våra Användarvillkor
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
National Cancer Center Hospital East ( Site 0001)
Kashiwa, Chiba, 277-8577, Japan
-
Toho University Sakura Medical Center ( Site 0003)
Sakura, Chiba, 285-8741, Japan
-
Yokohama City University Medical Center ( Site 0002)
Yokohama, Kanagawa, 232-0024, Japan
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- New pill aims to outsmart resistant prostate cancer
- Training a Patient's own immune cells to fight advanced prostate cancer
- Radioactive missile aims at prostate cancer that spread
- New PET tracer targets ACP3 to spot prostate cancer
- First-in-Human biologic JUR-003 put to the test against metastatic prostate cancer
- New drug combo targets CD46 in aggressive prostate cancer