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Study on the Effectiveness and Safety of SAR441566 for Adults with Moderate-to-Severe Ulcerative Colitis

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 ulcerative colitis, a condition that causes inflammation and sores in the colon and rectum. The treatment being tested is called SAR441566. The purpose of the study is to evaluate how effective and safe this treatment is for adults who have moderate-to-severe forms of ulcerative colitis.

Participants in the study will receive different doses of SAR441566 or a placebo to compare the outcomes. The study will monitor participants over a period of time to see if the treatment helps them achieve clinical remission, which means a significant reduction or disappearance of symptoms. The study will also look at other outcomes, such as improvements in symptoms reported by patients and changes observed during medical examinations.

The trial will last for several weeks, and participants will have regular check-ups to assess their progress. The study aims to gather information on how well SAR441566 works and its safety profile, which includes monitoring any side effects that may occur during the treatment period. This information will help determine if SAR441566 could be a beneficial treatment option for people with ulcerative colitis in the future.

The research process

The trial runs in 6 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, you will be randomly assigned to receive either the investigational medication SAR441566 or a placebo. A placebo is a substance with no active medication, used to compare the effects of the investigational drug.

  2. Step 2

    Medication administration

    You will receive the medication in a dose that is determined by the study protocol. The exact dosage and frequency will be explained to you by the study team. The medication will be administered over a period of 12 weeks.

  3. Step 3

    Regular check-ups

    Throughout the study, you will have regular check-ups to monitor your health and the effects of the medication. These check-ups will include physical examinations and may involve blood tests or other assessments as required by the study protocol.

  4. Step 4

    Monitoring and assessments

    Your progress will be monitored using a scoring system called the modified Mayo Score (mMS), which helps assess the severity of ulcerative colitis. This will be done at the start and at the end of the 12-week period to evaluate the effectiveness of the treatment.

  5. Step 5

    End of treatment evaluation

    At the end of the 12-week treatment period, your condition will be evaluated to determine if you have achieved clinical remission or response. This involves assessing improvements in symptoms and overall health.

  6. Step 6

    Follow-up

    After completing the treatment phase, there may be additional follow-up visits to monitor your health and gather further data on the long-term effects of the treatment.

Who can join the trial?

10 criteria

  • Participants must be male or female and aged between 18 to 75 years at the time of signing the consent form.
  • Participants should have active Ulcerative Colitis (UC) for at least 3 months before the screening, confirmed by a procedure called endoscopy during the screening period.
  • Participants must have moderate-to-severe UC at screening, defined by a specific score called the modified Mayo Score (mMS) of 5 to 9. This score includes:
    • A minimum rectal bleeding (RB) subscore of 1.
    • A minimum stool frequency (SF) subscore of 1.
    • A mMES of 2 or more, confirmed by a central reader.
    • A minimum total of all subscores of 5.
    • The disease must affect more than 15 cm from the anal verge.
    • Participants must have received prior treatment for UC, which includes:
      • No prior exposure to Advanced Therapy (AT), but having an inadequate response, loss of response, or intolerance to standard treatments like 5-ASA, 6-MP, AZA, MTX, oral or intravenous corticosteroids, or a history of corticosteroid dependence (meaning they cannot reduce corticosteroids without UC coming back).
      • Or, an inadequate response, loss of response, or intolerance to treatment with at least one approved AT, such as a biologic agent (like TNF antagonists, anti-integrin other than natalizumab, anti-IL-12/23, anti-IL-23, or experimental biologic UC treatments), or a small molecule (like a JAKi or S1PRm) for UC.
      • Participants must use contraception as per local regulations for those taking part in clinical studies.

Who cannot join the trial?

10 criteria

  • Patients with any other significant health condition that might interfere with the study.
  • Patients who have had a recent infection that required treatment with antibiotics.
  • Patients who have a history of severe allergic reactions.
  • Patients who are currently participating in another clinical trial.
  • Patients who have had surgery related to the digestive system in the past 6 months.
  • Patients who are pregnant or breastfeeding.
  • Patients who have a history of drug or alcohol abuse.
  • Patients who have been diagnosed with cancer in the past 5 years, except for skin cancer that is not melanoma.
  • Patients who have a history of heart disease.
  • Patients who have uncontrolled high blood pressure.
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Investigated drugs

SAR441566 is a medication being studied for its potential to help people with moderate-to-severe ulcerative colitis, which is a condition that causes inflammation and sores in the colon. This medication is being tested to see if it can help reduce the symptoms of ulcerative colitis and help patients achieve clinical remission, meaning their symptoms are significantly reduced or disappear. The study is looking at how effective and safe this medication is for people with this condition.

What is already known about the treatment

SAR441566 – SAR441566 is an investigational medication currently being studied for its potential to treat moderate-to-severe ulcerative colitis, a chronic inflammatory condition of the colon. It is administered orally, meaning it is taken by mouth in the form of a pill. The medication is in the clinical trial phase, specifically a Phase 2 study, which means it is being tested for its effectiveness and safety in humans. The main goal of this study is to see if SAR441566 can help patients achieve clinical remission, which means reducing or eliminating the symptoms of ulcerative colitis. The exact way SAR441566 works at the molecular level is still being researched, but it is believed to target specific pathways involved in inflammation. It falls under the pharmacological classification of anti-inflammatory agents.

Investigated diseases

Ulcerative Colitis – Ulcerative Colitis is a chronic inflammatory condition affecting the colon and rectum. It is characterized by inflammation and ulceration of the innermost lining of the large intestine. The disease typically begins in the rectum and can extend to involve the entire colon. Symptoms often include abdominal pain, diarrhea, and rectal bleeding. The inflammation can lead to frequent and urgent bowel movements. Over time, the disease can cause complications such as severe bleeding or perforation of the colon.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-520705-12-00Protocol codeDRI17822Estimated enrolment408 patientsSponsorSanofi-Aventis Recherche & Developpement

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).