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Study on the Safety and Effectiveness of Pembrolizumab and Drug Combination for Patients with Stage III Melanoma Eligible for Neoadjuvant Therapy

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 a type of skin cancer called Stage III melanoma. The study involves several investigational treatments, including pembrolizumab, also known by its code name MK-3475, which is a medication given through an infusion into the vein. Other treatments being studied include gebasaxturev (code name V937), which is injected directly into the tumor, and vibostolimab (code name MK-7684), which is also given by infusion. Additionally, the study includes a combination of pembrolizumab and favezelimab (code name MK-4280A), as well as MK-4830, both administered through infusions. Another treatment being tested is tretinoin, which is taken orally in capsule form.

The purpose of this study is to evaluate the safety and effectiveness of these treatments, either alone or in combination, for patients with Stage III melanoma who are candidates for neoadjuvant therapy, which is treatment given before the main treatment, usually surgery. Participants will receive one or more of these investigational treatments, and their health will be monitored to assess any side effects and the response of the cancer to the treatment. The study aims to determine how well these treatments work in shrinking the cancer before surgery and to understand any potential risks associated with them.

Throughout the study, participants will undergo regular health assessments, including reviews of their pathology results, which involve examining tissue samples to check for cancer cells. The study will also track the percentage of participants who experience side effects and those who achieve a complete response, meaning no cancer cells are detected in the tissue samples after treatment. The trial is designed to provide valuable information on the potential benefits and risks of these investigational treatments for Stage III melanoma.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    The trial begins with an initial assessment to confirm eligibility. This includes confirming a diagnosis of Stage IIIB, IIIC, or IIID melanoma that can be surgically removed.

    A baseline tumor biopsy is required to proceed.

  2. Step 2

    Treatment phase

    Participants receive treatment with investigational agents, either alone or in combination with pembrolizumab. The specific treatment regimen is determined based on the study arm assigned.

    The medications are administered through different routes: pembrolizumab and other agents like vibostolimab and MK-4830 are given as intravenous infusions. Gebasaxturev is used intratumorally, and tretinoin is taken orally.

    The frequency and duration of administration depend on the specific investigational agent and study protocol.

  3. Step 3

    Monitoring and evaluation

    Participants are monitored for safety and any adverse events throughout the treatment phase.

    Regular assessments are conducted to evaluate the response to treatment, including pathological complete response (pCR) and other response rates.

  4. Step 4

    Follow-up

    After completing the treatment phase, participants enter a follow-up period to monitor long-term outcomes such as recurrence-free survival.

    The follow-up period continues until the estimated end date of the trial in June 2030.

Who can join the trial?

9 criteria

  • The patient must have a type of skin cancer called **melanoma** that is confirmed by a test called **histology** or **cytology**.
  • The melanoma must be at a stage called **Stage IIIB, IIIC, or IIID**, which means it is advanced but can still be removed by surgery.
  • The patient should not have received any treatment for Stage IIIB, IIIC, or IIID melanoma, except for surgery to remove the primary melanoma or prior radiation therapy to the primary melanoma.
  • The patient must provide a sample of their tumor for testing, known as a **baseline tumor biopsy**.
  • Male patients receiving a treatment called **gebasaxturev** must either not engage in heterosexual intercourse or agree to use birth control during the study and for at least 120 days after the last dose.
  • Male patients receiving a treatment called **ATRA** must either not engage in heterosexual intercourse or agree to use birth control during the study and for at least 7 days after the last dose.
  • Female patients must not be pregnant or breastfeeding. They must either not be able to have children or use a highly effective birth control method or abstain from heterosexual intercourse during the study and for at least 120 days after the last dose of certain treatments, or 30 days after the last dose of ATRA, whichever is longer.
  • The patient must have **adequate organ function**, meaning their organs are working well enough to participate in the study.
  • The patient must have recovered from any side effects of previous treatments to a mild level, known as **Grade 1 or less**, except for hair loss (alopecia).

Who cannot join the trial?

5 criteria

  • Patients with a different stage of melanoma than **Stage IIIB, IIIC, or IIID** cannot participate. **Melanoma** is a type of skin cancer, and the stages refer to how advanced the cancer is.
  • Patients who have experienced **adverse events** from similar treatments in the past are excluded. **Adverse events** are unwanted side effects or reactions to a treatment.
  • Patients who are not within the specified **age range** for the study cannot participate. The age range is determined by the study and includes specific age groups.
  • Patients who are not part of the specified **clinical trial groups** are excluded. These groups are defined by the study to include certain characteristics or conditions.
  • Patients who are part of a **vulnerable population** may be excluded. A **vulnerable population** includes groups of people who may need special protection or consideration in a study.
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Investigated drugs

  • Pembrolizumab

    is a medication used in this trial to help the body's immune system fight melanoma, a type of skin cancer. It works by blocking a specific protein that prevents the immune system from attacking cancer cells, allowing the immune system to better target and destroy these cells.

  • Investigational Agents

    are new treatments being tested in this trial to see if they are safe and effective for treating melanoma. These agents are not yet approved for general use and are being studied to understand their potential benefits and side effects when used alone or in combination with pembrolizumab.

What is already known about the treatment

Pembrolizumab – Pembrolizumab is administered as an intravenous infusion, typically given in a clinical setting. It is currently well-established in medical literature as an immunotherapy for various cancers, including melanoma. The main therapeutic indication for pembrolizumab in this trial is for treating advanced stages of melanoma, specifically stages IIIB, IIIC, or IIID. At the molecular level, pembrolizumab works by blocking the PD-1 pathway, which helps the immune system recognize and attack cancer cells more effectively. It is classified as a monoclonal antibody and is part of the broader class of immune checkpoint inhibitors.

Investigated diseases

  • Stage IIIB Melanoma

    This is a form of skin cancer where the melanoma has spread to nearby lymph nodes or lymphatic channels but not to distant sites. It may involve satellite tumors or in-transit metastases, which are small tumors that appear near the primary tumor site. The disease progresses as the cancer cells invade deeper layers of the skin and nearby tissues, potentially affecting lymph nodes.

  • Stage IIIC Melanoma

    At this stage, melanoma has spread to one or more nearby lymph nodes or has formed small tumors in the skin or lymphatic channels near the original tumor. The cancer may also have ulcerated, meaning the skin over the tumor has broken down. Progression involves further spread to nearby lymph nodes and tissues, increasing the complexity of the disease.

  • Stage IIID Melanoma

    This is an advanced stage of melanoma where the cancer has spread extensively to nearby lymph nodes and possibly to nearby skin or lymphatic channels. The tumor is often ulcerated and may involve multiple lymph nodes. The disease progresses with significant local spread, making it more challenging to manage.

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-506314-51-00Protocol codeMK-3475-02CEstimated enrolment136 patientsSponsorMerck Sharp & Dohme LLC

sourced from the EU Clinical Trials Register and site verification

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