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Study of Pembrolizumab for Patients with Early Stage Non-Small Cell Lung Cancer After Surgery and Standard Therapy

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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 lung cancer known as Non-Small Cell Lung Cancer (NSCLC), specifically in its early stages, which are referred to as Stage IB, II, and IIIA. The study is investigating the effects of a treatment called pembrolizumab, also known by its code name MK-3475, compared to a placebo. Pembrolizumab is a type of medication known as an anti-PD-1 monoclonal antibody, which is designed to help the immune system fight cancer cells.

The purpose of the study is to determine if pembrolizumab can improve the time patients remain free from cancer after they have undergone surgery and completed standard therapy. Participants in the study will receive either pembrolizumab or a placebo through an intravenous infusion, which means the medication is given directly into a vein. The study will last for a period of up to 52 weeks, during which participants will be monitored regularly to assess their health and the effectiveness of the treatment.

This trial is particularly interested in patients who have had their lung cancer surgically removed and have completed any additional recommended treatments. The study aims to see if pembrolizumab can help prevent the cancer from returning, especially in patients whose tumors show a strong presence of a protein called PD-L1. Participants will be closely observed by healthcare professionals throughout the study to ensure their safety and to gather important information about the treatment's impact on their health.

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

    Registration

    Provide written consent for tumor testing. This is necessary before joining the study.

    Ensure no chronic use of immunosuppressive agents or systemic corticosteroids in the last 3 days before the first infusion.

    Confirm stage IB (T ≥ 4 cm), II, or IIIA non-small cell lung cancer (NSCLC) after complete surgical removal of the tumor.

    Submit a tumor sample for PD-L1 testing. This is required for participation, although the level of PD-L1 does not affect eligibility.

  2. Step 2

    Central confirmation of PD-L1 status

    PD-L1 status must be confirmed through a central process. This is necessary to proceed to the next step.

  3. Step 3

    Randomization

    Provide written consent for participation in the main study.

    Ensure no evidence of disease through clinical examination and imaging tests within 12 weeks before randomization.

    Adjuvant chemotherapy is optional but recommended for certain stages. If received, it must be completed within specific timeframes relative to surgery and randomization.

    Ensure no history of certain lung diseases or active autoimmune diseases requiring treatment in the past 2 years.

    Confirm adequate organ function and absence of severe comorbidities that could affect participation.

  4. Step 4

    Treatment administration

    Receive pembrolizumab or placebo intravenously. The specific dosage and frequency will be determined by the study protocol.

    Continue treatment as per the study schedule, monitoring for any side effects or changes in health status.

  5. Step 5

    Follow-up

    Undergo regular health assessments to monitor disease status and any potential side effects of the treatment.

    Participate in follow-up visits as scheduled by the study protocol to ensure ongoing evaluation of health and treatment efficacy.

Who can join the trial?

16 criteria

  • Must be at least 18 years old.
  • Must have a confirmed diagnosis of **NSCLC** (Non-Small Cell Lung Cancer) at specific stages (IB, II, or IIIA) after complete surgical removal of the tumor.
  • Must provide a tumor sample for testing a protein called **PD-L1**.
  • Must have no signs of disease based on recent medical exams and scans.
  • Must not have a history of certain lung diseases or active autoimmune diseases that required treatment in the past 2 years.
  • Must not have had another type of cancer unless it has been in remission for at least 5 years, with some exceptions like certain skin cancers.
  • Must not have had a tissue or organ transplant.
  • Must not have any active infections that need treatment.
  • Must not have any unresolved side effects from previous surgery or chemotherapy, except for hair loss, tiredness, nerve pain, or loss of appetite.
  • Female patients who can have children must have a negative pregnancy test and agree to use two forms of birth control during the study and for a period after.
  • Male patients with partners who can have children must agree to use two forms of birth control during the study and for a period after.
  • Female patients who are breastfeeding must stop nursing before starting the study treatment and for a period after.
  • Must have adequate organ function based on recent tests.
  • Must not have had certain treatments like radiotherapy or specific immune therapies for the current cancer.
  • Must not be participating in another clinical trial or using experimental treatments recently.
  • Must not have a known history of **HIV** or active **Hepatitis B** or **C**.

Who cannot join the trial?

5 criteria

  • Patients who have not completed radical surgery, which means a major operation to remove lung cancer, cannot participate.
  • Patients who have not had a lobectomy or pneumonectomy, which are types of lung surgeries, are excluded.
  • Patients who have not received or completed standard adjuvant chemotherapy, which is additional cancer treatment given after surgery, are not eligible.
  • Patients who do not have Stage IB (T ≥ 4 cm), II, or IIIA NSCLC, which are specific stages of non-small cell lung cancer, cannot join the study.
  • Patients who are not in the PDL1 strong positive subgroup or the overall population, which refers to specific groups based on a protein that can affect cancer treatment, are excluded.
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Investigated drugs

Pembrolizumab is a medication used in this clinical trial. It is an anti-PD-1 monoclonal antibody, which means it helps the immune system recognize and attack cancer cells. In this study, pembrolizumab is given to patients with early-stage non-small cell lung cancer (NSCLC) after they have had surgery to remove the cancer and possibly completed standard chemotherapy. The goal is to see if pembrolizumab can help prevent the cancer from coming back.

What is already known about the treatment

Pembrolizumab – This medication is administered as an intravenous infusion, typically given in a clinical setting. It is currently well-established in medical literature as an immunotherapy treatment for various cancers, including non-small cell lung cancer (NSCLC). Pembrolizumab is primarily indicated for patients with early-stage NSCLC after surgery and standard chemotherapy. It works by blocking the PD-1 pathway, which helps the immune system recognize and attack cancer cells more effectively. Pembrolizumab is classified as a monoclonal antibody and is part of the broader category of immune checkpoint inhibitors.

Investigated diseases

Non-Small Cell Lung Cancer (NSCLC) – This is a type of lung cancer that includes several subtypes such as squamous cell carcinoma, adenocarcinoma, and large cell carcinoma. It is the most common type of lung cancer, accounting for about 85% of cases. NSCLC typically grows and spreads more slowly than small cell lung cancer. The disease is often diagnosed at an advanced stage, as early symptoms can be mild or mistaken for other conditions. As it progresses, NSCLC can spread to other parts of the body, including the lymph nodes, bones, brain, and liver. The progression and symptoms can vary depending on the stage and specific subtype of the cancer.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-509137-39-00Protocol codeMK-3475-091Estimated enrolment739 patientsSponsorMerck Sharp & Dohme LLC

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