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Study of Opevesostat, Olaparib, and Cabazitaxel in Patients with Advanced Prostate Cancer

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying treatments for metastatic castration-resistant prostate cancer (mCRPC), a type of prostate cancer that continues to grow and spread even when the amount of male hormones in the body is reduced to very low levels. The study will explore the safety and effectiveness of different treatment combinations, including the use of Olaparib and Opevesostat (also known by its code name MK-5684 tosylate), as well as other medications like Cabazitaxel and Docetaxel. These treatments will be compared to a placebo to understand their impact on the disease.

The purpose of the study is to evaluate how well these treatments work and how safe they are for patients. Participants will receive one or more of these medications, and their health will be monitored closely throughout the study. The study will also look at how the treatments affect levels of prostate-specific antigen (PSA), a substance in the blood that can indicate the presence of prostate cancer. The study will be conducted over several years, with regular check-ups and assessments to track the progress of the disease and any side effects experienced by participants.

By participating in this study, researchers hope to gather important information that could lead to better treatment options for those with advanced prostate cancer. The study will help determine the best doses and combinations of these medications to improve patient outcomes. The ultimate goal is to find effective ways to manage and treat metastatic castration-resistant prostate cancer, providing hope for patients and their families.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Upon joining the study, the participant will be informed about the trial's objectives and procedures.

    The participant will provide informed consent, acknowledging understanding of the study's purpose and potential risks.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to confirm eligibility, including a review of medical history and current health status.

    Tests may include blood tests, imaging studies, and other necessary evaluations to establish a baseline for the study.

  3. Step 3

    Treatment phase

    The participant will begin the treatment phase, which involves receiving specific medications as part of the study protocol.

    Medications may include dexamethasone taken orally, cabazitaxel administered intravenously, and olaparib in the form of film-coated tablets.

    The frequency and dosage of each medication will be determined by the study protocol and adjusted based on the participant's response and tolerance.

  4. Step 4

    Monitoring and follow-up

    Regular monitoring will occur throughout the study to assess the participant's response to treatment and any side effects.

    This may include routine blood tests, imaging studies, and other assessments as required by the study protocol.

  5. Step 5

    Completion of treatment

    Upon completion of the treatment phase, a final assessment will be conducted to evaluate the overall response to the study medications.

    The participant will be informed of the study's findings related to their treatment and any further recommendations.

  6. Step 6

    Post-study follow-up

    After the study concludes, follow-up visits may be scheduled to monitor the participant's long-term health and any lasting effects of the treatment.

    These visits will help gather additional data on the safety and efficacy of the treatment combinations used in the study.

Who can join the trial?

11 criteria

  • Must have a confirmed diagnosis of prostate cancer, specifically a type called adenocarcinoma, and it should not include a type called small cell histology.
  • If you have a history of Hepatitis C, you can participate if the virus is not detectable in your blood.
  • Your prostate cancer should have progressed, and you should have received a treatment called androgen deprivation therapy (ADT) or had a surgery called bilateral orchiectomy within 6 months before the study starts.
  • There should be evidence that your disease has progressed after stopping certain medications for a specific time: more than 4 weeks after flutamide or more than 6 weeks after bicalutamide or nilutamide, if these were your last treatments.
  • You must currently have metastatic disease, which means the cancer has spread to other parts of the body.
  • You should have been treated with 1 to 2 new hormonal treatments for prostate cancer, and your disease should have progressed during or after these treatments.
  • If you are receiving treatment to prevent bone loss, such as bisphosphonate or denosumab, you must have been on a stable dose for at least 4 weeks before joining the study.
  • If you had side effects from previous cancer treatments, they must have improved to a mild level or returned to how they were before treatment.
  • If you have HIV, it must be well controlled with medication.
  • If you have Hepatitis B, you can participate if you have been on antiviral treatment for at least 4 weeks and the virus is not detectable in your blood.
  • Only male participants are eligible for this study.

Who cannot join the trial?

3 criteria

  • Patients who do not have metastatic castration-resistant prostate cancer (mCRPC) cannot participate. This is a type of prostate cancer that has spread to other parts of the body and does not respond to treatments that lower testosterone.
  • Only male patients are eligible, so female patients cannot participate.
  • Patients who are considered part of a vulnerable population, such as those who cannot give informed consent, are not eligible.
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Investigated drugs

MK-5684 is an investigational medication being studied for its potential to treat metastatic castration-resistant prostate cancer. This medication is being tested alone or in combination with other treatments to determine its safety and effectiveness. The study aims to understand how well patients tolerate the medication and to find the best dose for future studies.

What is already known about the treatment

MK-5684 – This medication is administered orally and is currently being studied in clinical trials for its safety and effectiveness in treating metastatic castration-resistant prostate cancer (mCRPC). It is in the investigational stage, meaning it is not yet approved for general medical use but is being evaluated in research settings. The main therapeutic indication for MK-5684 is mCRPC, a type of prostate cancer that continues to progress despite hormone therapy. At the molecular level, MK-5684 works by targeting specific pathways involved in cancer cell growth and survival, although the exact mechanism is still under investigation. It is classified pharmacologically as an investigational cancer therapy.

Investigated diseases

Metastatic Castration-Resistant Prostate Cancer (mCRPC) – This is a type of prostate cancer that continues to grow and spread to other parts of the body despite treatments that lower testosterone levels. The disease is characterized by its resistance to hormonal therapy, which is typically used to manage prostate cancer. As the cancer progresses, it may spread to bones, lymph nodes, or other organs, leading to various symptoms depending on the areas affected. Patients with mCRPC often experience an increase in prostate-specific antigen (PSA) levels, which is a marker used to monitor the progression of prostate cancer. The disease can cause symptoms such as bone pain, urinary issues, and fatigue, which can impact the quality of life. The progression of mCRPC is typically monitored through imaging studies and PSA levels to assess the spread and activity of the cancer.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-506288-33-00Protocol codeMK-5684-01AEstimated enrolment311 patientsSponsorMerck Sharp & Dohme LLC

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