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Study of mRNA-4157 and Pembrolizumab for Patients with High-Risk Stage II-IV Melanoma

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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 a type of skin cancer called Melanoma. The study is investigating a new treatment combination for patients who have had their melanoma surgically removed but are at high risk of the cancer returning. The treatment being tested includes a new investigational drug called V940 (mRNA-4157) and an existing medication known as Pembrolizumab, which is also referred to by its brand name, KEYTRUDA. Pembrolizumab is a type of medication that helps the immune system fight cancer cells. The study will compare the effects of V940 plus Pembrolizumab against a placebo plus Pembrolizumab to see which is more effective in preventing the cancer from coming back.

The purpose of this study is to determine if the combination of V940 and Pembrolizumab can improve the time patients remain free from cancer recurrence, known as Recurrence-Free Survival (RFS). Participants in the study will receive either the combination of V940 and Pembrolizumab or a placebo and Pembrolizumab. The study is designed to be "double-blind," meaning neither the participants nor the researchers will know who is receiving the actual treatment or the placebo, to ensure unbiased results.

Throughout the study, participants will receive regular treatments and check-ups to monitor their health and the status of their melanoma. The study will also track other important outcomes, such as the time until the cancer spreads to distant parts of the body, known as Distant Metastasis Free Survival (DMFS), overall survival rates, and any side effects experienced by participants. The study aims to provide valuable information on the effectiveness and safety of the new treatment combination for melanoma patients.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes verifying that the melanoma has been surgically removed and that there is no evidence of disease.

    A tumor sample is required for sequencing, and organ function tests are performed to ensure adequate health status.

  2. Step 2

    Randomization

    Participants are randomly assigned to one of two groups: one receiving the experimental treatment and the other receiving a placebo.

    Both groups will receive pembrolizumab, a medication administered through an intravenous infusion.

  3. Step 3

    Treatment administration

    The experimental group receives V940 (mRNA-4157) via intramuscular injection, while the control group receives a placebo injection.

    Pembrolizumab is administered as a 25 mg/mL solution for infusion. The frequency and duration of administration are determined by the study protocol.

  4. Step 4

    Monitoring and follow-up

    Participants are monitored for recurrence-free survival, which is the primary goal of the study.

    Secondary outcomes include distant metastasis-free survival, overall survival, and the occurrence of any adverse events.

    Quality of life and physical functioning are also evaluated through specific questionnaires.

  5. Step 5

    Completion and analysis

    The study is expected to conclude by September 2030. Data collected will be analyzed to determine the effectiveness and safety of the treatment.

    Participants' health and well-being are assessed throughout the study to ensure safety and gather comprehensive results.

Who can join the trial?

13 criteria

  • The patient must have had a type of skin cancer called melanoma that has been surgically removed and confirmed to be at stage IIB to IV.
  • If the patient has a Hepatitis C virus (HCV) infection, the virus must not be detectable in their blood at the time of screening.
  • If the patient is infected with HIV, their infection must be well controlled with medication.
  • The patient must not have received any treatment for their melanoma other than surgery.
  • The patient must have had surgery that completely removed the cancer, leaving them free of the disease, within 13 weeks before starting the study medication.
  • The patient must have a sample of their tumor preserved in a specific way (called formalin fixed paraffin embedded) that can be used for genetic testing.
  • The patient must be free of cancer at the start of the study, with no return of cancer in the original area or spread to other parts of the body, including the brain.
  • Any suspicious areas that can be biopsied must be confirmed to not be cancerous.
  • The patient must have an Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1, which means they are fully active or have some symptoms but do not need bed rest during the day.
  • The patient must have organs that are functioning well, with tests done within 7 days before starting the study treatment.
  • If the patient has a Hepatitis B virus (HBV)</b) infection, they must have been on antiviral treatment for at least 4 weeks and have no detectable virus in their blood before being assigned to a treatment group.
  • The study is open to both male and female patients.
  • The study is for patients who are not considered part of a vulnerable population.

Who cannot join the trial?

10 criteria

  • Patients with any other type of cancer besides melanoma cannot participate. Melanoma is a type of skin cancer.
  • Patients who have had a different cancer in the past, unless it was successfully treated and has not come back, are excluded.
  • Patients with serious heart problems, such as heart failure or a recent heart attack, are not eligible.
  • Patients with uncontrolled high blood pressure cannot join the study.
  • Patients with active infections, like hepatitis or HIV, are excluded.
  • Patients who are pregnant or breastfeeding cannot participate.
  • Patients who have had an organ transplant are not eligible.
  • Patients who are taking certain medications that might interfere with the study treatment are excluded.
  • Patients with autoimmune diseases, where the immune system attacks the body, are not eligible.
  • Patients who have received another experimental treatment within the last 4 weeks cannot participate.
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Investigated drugs

  • V940 (mRNA-4157)

    is an investigational vaccine designed to help the immune system recognize and attack melanoma cells. It is being studied to see if it can improve outcomes for patients with high-risk melanoma when used in combination with another medication.

  • Pembrolizumab

    is a medication that helps the immune system fight cancer by blocking a specific protein that prevents the immune system from attacking cancer cells. It is used in this trial to see if it can work better when combined with the investigational vaccine V940.

What is already known about the treatment

  • Pembrolizumab

    This medication is administered as an intravenous infusion, typically in a clinical setting. It is currently well-established in medical literature as an immunotherapy used to treat various cancers, including melanoma. Pembrolizumab works by blocking a specific protein on immune cells, allowing them to better attack cancer cells. It is classified as a monoclonal antibody and is part of a group of drugs known as immune checkpoint inhibitors.

  • V940 (mRNA-4157)

    This investigational medication is administered via injection and is currently being studied in clinical trials for its potential use in treating melanoma. It is designed to work as a personalized cancer vaccine, stimulating the immune system to recognize and attack cancer cells. V940 is classified as an mRNA-based therapeutic, which represents a novel approach in cancer treatment by using messenger RNA to instruct cells to produce proteins that trigger an immune response.

Investigated diseases

Melanoma – Melanoma is a type of skin cancer that develops from the pigment-producing cells known as melanocytes. It often appears as a new mole or a change in an existing mole, typically with irregular borders and multiple colors. Melanoma can occur anywhere on the body but is most common on areas exposed to the sun, such as the back, legs, arms, and face. As it progresses, melanoma can grow deeper into the skin and spread to other parts of the body, including lymph nodes and internal organs. Early detection is crucial, as melanoma can be more effectively managed when identified at an early stage. Regular skin checks and awareness of changes in moles or skin appearance are important for early identification.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-503652-27-00Protocol codeV940-001Estimated enrolment1 137 patientsSponsorMerck Sharp & Dohme LLC

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