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Study on the Safety and Effects of Favezelimab and Pembrolizumab for Patients with Blood Cancers

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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 hematologic malignancies, which are types of cancer that affect the blood, bone marrow, and lymph nodes. The study involves two medications: favezelimab and pembrolizumab. Favezelimab, also known by its code name MK-4280, is a solution given through an intravenous infusion, which means it is administered directly into the bloodstream. Pembrolizumab, also known as Keytruda or MK-3475, is also given as an intravenous infusion.

The purpose of this study is to evaluate the safety and effectiveness of using favezelimab in combination with pembrolizumab, as well as to assess each medication when used alone. Participants in the study will receive these treatments and will be monitored for any side effects or reactions. The study aims to determine the best dose for future research and to understand how well these treatments work together or separately in treating hematologic malignancies.

Throughout the study, participants will undergo regular check-ups and tests to monitor their health and the effects of the treatment. This includes measuring the concentration of the medications in the blood and observing any changes in the cancer. The study will help researchers gather important information about these treatments, which could lead to better options for patients with hematologic malignancies in the future.

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

    Joining the study

    Upon joining the study, the patient will undergo initial assessments to confirm eligibility. This includes providing a tumor biopsy for analysis and ensuring the disease can be measured accurately through imaging techniques like CT or MRI.

    The patient must have a performance status of 0 or 1, indicating they are fully active or restricted in physically strenuous activity but ambulatory.

  2. Step 2

    Treatment phase

    The treatment involves the administration of two medications: favezelimab and pembrolizumab. Both are given as a solution for infusion, which means they are delivered directly into the bloodstream through an intravenous (IV) line.

    The specific dosage and frequency of administration will be determined based on the patient's response and the study's phase. The goal is to find a safe and effective dose combination.

  3. Step 3

    Monitoring and assessments

    Throughout the study, the patient will be closely monitored for any side effects or adverse events. This includes regular check-ups and blood tests to measure the concentration of favezelimab and pembrolizumab in the serum.

    The patient's response to the treatment will be evaluated through imaging and other diagnostic tests to determine the objective response rate.

  4. Step 4

    Completion of the study

    The study is expected to continue until October 2027. Upon completion, the patient's overall health and response to the treatment will be assessed to determine the long-term effects and efficacy of the medication combination.

Who can join the trial?

6 criteria

  • The patient must have a **measurable disease**. This means there should be at least one tumor that can be accurately measured in two directions using special imaging tests like a CT scan or MRI. The tumor should be larger than 15 mm in its longest part or larger than 10 mm in its shortest part.
  • The patient must be able to provide a **tumor biopsy**. This is a small sample of the tumor tissue that can be taken from a previous test done within the last 3 months or a new test done during the screening process.
  • The patient must have a **performance status** of 0 or 1 on the **Eastern Cooperative Oncology Group (ECOG)** scale. This is a way to measure how well a patient can perform daily activities. A score of 0 means the patient is fully active, and a score of 1 means the patient is restricted in physically strenuous activity but can carry out light work.
  • The patient must be within certain age ranges, which typically include adults.
  • Both **female and male** patients are eligible to participate.
  • The study may include **vulnerable populations**, which means it considers groups that might need special attention or care.

Who cannot join the trial?

5 criteria

  • Patients with certain types of blood cancers, known as hematologic malignancies, cannot participate. These are cancers that start in blood-forming tissue, such as the bone marrow, or in the cells of the immune system.
  • Individuals who are not within the specified age range for the study are excluded. The study is open to certain age groups only.
  • Participants who are not part of the specified clinical trial groups are not eligible. This means the study is looking for people with specific characteristics or conditions.
  • Both men and women can participate, but if someone does not meet other gender-related criteria, they may be excluded.
  • People who are considered part of a vulnerable population may not be eligible. This term refers to groups who might be at a higher risk of harm or exploitation, such as children, pregnant women, or those with limited decision-making capacity.
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Investigated drugs

  • MK-4280

    is an investigational medication being studied for its safety and effectiveness in treating blood cancers. It is being tested both on its own and in combination with another medication to see how well it works and how safe it is for patients.

  • Pembrolizumab

    is a medication already used in cancer treatment. In this study, it is being combined with MK-4280 to evaluate if the combination is more effective in treating blood cancers. Pembrolizumab is also being tested alone to assess its safety and tolerability in this specific group of patients.

What is already known about the treatment

  • MK-4280

    This medication is administered intravenously and is currently being studied in clinical trials for its safety and effectiveness in treating hematologic malignancies. It is in the early phases of clinical research, focusing on determining the appropriate dosage and evaluating its safety both as a standalone treatment and in combination with pembrolizumab. MK-4280 is designed to target specific proteins on immune cells, potentially enhancing the body's immune response against cancer cells. It falls under the category of immunotherapy agents.

  • Pembrolizumab

    This medication is also administered intravenously and is well-established in medical literature as an immunotherapy used to treat various types of cancer. In the context of the current clinical trial, it is being evaluated for its safety and effectiveness in combination with MK-4280 for hematologic malignancies. Pembrolizumab works by blocking a specific protein on immune cells, allowing the immune system to better detect and attack cancer cells. It is classified as a checkpoint inhibitor.

Investigated diseases

Hematologic malignancies – These are cancers that begin in the blood-forming tissue, such as the bone marrow, or in the cells of the immune system. They include various types of leukemia, lymphoma, and myeloma. These diseases often result in the production of abnormal blood cells, which can interfere with normal blood cell function. As they progress, they may cause symptoms like fatigue, fever, frequent infections, and easy bruising or bleeding. The progression can vary widely depending on the specific type of hematologic malignancy. They are typically characterized by the uncontrolled growth of blood cells, which can spread to other parts of the body.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase ITrial ID2023-503587-17-00Protocol codeMK-4280-003Estimated enrolment145 patientsSponsorMerck Sharp & Dohme LLC

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).