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Study of GLPG3667 for Adults with Active Systemic Lupus Erythematosus

Fast replyInvestigationalNo 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 the effects of a new treatment for Systemic Lupus Erythematosus (SLE), a disease where the immune system mistakenly attacks healthy tissues in the body, causing inflammation and damage to various organs. The treatment being tested is called GLPG3667, which is taken as a capsule. The study will compare the effects of GLPG3667 to a placebo, which looks like the treatment but does not contain the active ingredient.

The purpose of the study is to evaluate how well GLPG3667 works in reducing the activity of SLE and to assess its safety and tolerability. Participants in the study will receive either GLPG3667 or a placebo, and neither the participants nor the researchers will know who is receiving which treatment. This is known as a double-blind study. The study will last for several weeks, during which participants will take the medication orally and attend regular check-ups to monitor their health and the effects of the treatment.

Throughout the study, researchers will collect information on how the treatment affects the symptoms of SLE, such as joint pain and skin rashes, and will also monitor for any side effects. The study aims to determine if GLPG3667 can help manage the symptoms of SLE and improve the quality of life for those affected by this condition. Participants will be closely monitored to ensure their safety and well-being throughout the trial.

The research process

The trial runs in 2 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    <b>medication administration</b>

    You will receive either the test drug, known as glpg3667, or a placebo. a placebo is a pill that contains no active medicine and is used for comparison purposes.

    If assigned to the glpg3667 group, you will take 150 mg of the medication in capsule form by oral use (swallowing).

  2. Step 2

    <b>study monitoring and evaluation</b>

    The study involves monitoring the effects of the treatment on systemic lupus erythematosus, which is an autoimmune condition where the immune system attacks healthy tissues.

    Measurements regarding disease activity, such as the sri-4 response (a way to measure if symptoms improve), the bicla response, and clasi-a score (used to assess skin involvement), will be recorded at various stages.

    At week 32 and week 48, assessments will be made to check for lupus low disease activity state, which refers to a period where the disease is less active, as well as changes in joint counts (checking for tender or swollen joints).

    The safety and tolerability of the medication will be monitored throughout the process by observing any adverse events, which are unexpected or unpleasant side effects.

Who can join the trial?

8 criteria

  • Both men and women can participate if they are between 18 and 75 years old on the day they sign the consent form.
  • Participants must have a confirmed diagnosis of Systemic Lupus Erythematosus (SLE), which is a long-term disease where the immune system attacks the body's own tissues, and this diagnosis must have been made at least 24 weeks before the study begins.
  • The disease must be currently active, measured by a specific scoring system called SLEDAI-2K. To qualify, a person must have a total score of at least 6 points and a clinical score (based on physical symptoms rather than lab tests) of at least 4 points.
  • Certain symptoms, such as lupus headaches, alopecia (hair loss), organic brain syndrome (changes in mental function), and mucous membrane ulceration (sores in the mouth or nose), will not be used to reach the required score.
  • Laboratory tests must show a positive result for at least one of the following: antinuclear antibodies (ANA), which are proteins that attack cell nuclei; anti-dsDNA, which are specific antibodies found in lupus; or anti-Smith (anti-Sm) antibodies.
  • Participants must show signs of the disease in specific areas, such as the mucocutaneous system (skin and mucous membranes) or the musculoskeletal system (joints and muscles) due to arthritis (joint swelling and pain), based on a specialized rating scale called BILAG.
  • Participants must have been taking at least one type of background therapy for at least 12 weeks before the study, and this medication must stay at the same dose throughout the trial. This includes either one immunosuppressant (a medicine that lowers the immune system's activity) or one antimalarial (a medicine often used to treat lupus symptoms).
  • The use of corticosteroids (such as prednisone, which reduces inflammation) or NSAIDs (non-steroidal anti-inflammatory drugs, which are medicines used to reduce pain and swelling) is allowed, but these must have been taken at a stable dose for at least 2 weeks before the study begins.

Who cannot join the trial?

15 criteria

  • People with severe lupus nephritis, which is a serious inflammation of the kidneys caused by lupus, that requires treatment with cytotoxic agents (medicines that kill rapidly dividing cells) or high doses of corticosteroids (strong anti-inflammatory drugs).
  • People with kidney disease that is not well-controlled, unless the disease is stable with specific protein levels in the urine as measured by a urine protein: creatinine ratio (UPCR).
  • People with poorly controlled long-term problems with the heart, lungs, or kidneys.
  • People with severe renal impairment, which means the kidneys are not working well enough, specifically an estimated glomerular filtration rate (eGFR) of less than 30 mL/minute/1.73 m2.
  • People who have previously used tyrosine kinase 2 (TYK2) inhibitors, which are a specific type of medication.
  • Women who are pregnant, breastfeeding, or planning to become pregnant or breastfeed during the study.
  • People who have used prohibited therapies (medicines not allowed in this study) within the required washout period (the time needed for a drug to leave your system).
  • People with a history of catastrophic antiphospholipid syndrome, a serious condition that causes blood clots, such as a pulmonary embolism (blood clot in the lung), stroke, or deep vein thrombosis (blood clot in a deep vein), or those with multiple unexplained pregnancy losses.
  • People with active or unstable lupus neuropsychiatric manifestations, which are brain or nerve-related symptoms caused by lupus, though some specific nerve issues like polyneuropathy are allowed.
  • People whose lupus was caused by a specific medication, known as drug-induced systemic lupus erythematosus.
  • People with a chronic hepatitis B virus (HBV) infection, which is a virus that attacks the liver.
  • People with a chronic hepatitis C virus (HCV) infection, which is another virus that can cause liver disease.
  • People with a history of or current immunosuppressive condition (a condition where the immune system is weakened) or a history of opportunistic infections, which are infections that happen more easily in people with weak immune systems, such as HIV.
  • People who test positive for SARS-CoV-2 (the virus that causes COVID-19) through an antigen test or a RT-PCR test (a highly sensitive laboratory test used to detect viral genetic material).
  • People with a history of active tuberculosis (TB) or those who test positive on a QuantiFERON-TB Gold Plus test (a blood test used to check for TB infection).
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Investigated drugs

GLPG3667 is an experimental medication taken by mouth in capsule form. It is being studied to see if it can help reduce disease activity in adults who have active systemic lupus erythematosus, an autoimmune condition.

What is already known about the treatment

  • GLPG3667

    This medication is an experimental drug taken as a capsule by mouth. It is currently being studied in clinical trials to determine if it can effectively treat systemic lupus erythematosus, an autoimmune disease. The drug works by targeting specific signaling proteins in the immune system to help reduce the overactive inflammation that causes tissue damage. It is classified as an investigational small molecule modulator of immune pathways.

  • Placebo

    This is an inactive substance administered in the same form and via the same route as the study drug to serve as a comparison. It contains no active medicine and is used in clinical research to ensure that the observed effects are actually caused by the test drug. It has no therapeutic effect and is used purely as a control tool in scientific studies.

Investigated diseases

Systemic Lupus Erythematosus - This is a condition where the body's immune system mistakenly attacks healthy tissues and organs. It can affect many different parts of the body, including the skin, joints, kidneys, blood cells, brain, heart, and lungs. The disease often progresses through periods of high activity followed by periods of relative calm. During active phases, inflammation can cause damage to various organ systems. Skin rashes and joint swelling are common signs as the condition moves forward.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-503183-16-00Protocol codeGLPG3667-CL-215Estimated enrolment196 patientsSponsorGalapagos

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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).