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Study on Long-term Safety of Zasocitinib for Adults with Moderate to Severe Ulcerative Colitis and Crohn's Disease

Verified siteInvestigationalNo 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 long-term safety and tolerability of a medication called zasocitinib, also known by its code name TAK-279. The study involves participants who have either Ulcerative Colitis or Crohn's Disease, both of which are conditions that cause inflammation in the digestive tract. These diseases can lead to symptoms like abdominal pain, diarrhea, and fatigue, and are considered moderately to severely active in the participants of this study.

The purpose of the study is to evaluate how well participants tolerate the medication over an extended period. Participants who have already shown a response to the treatment in previous trials will continue to take zasocitinib in capsule form. The study will last for up to 108 weeks, during which time participants will be monitored for any side effects or changes in their health. Some participants will receive a placebo, which is a substance with no active medication, to compare the effects of the actual drug.

Throughout the study, participants will have regular check-ups to assess their health, including monitoring vital signs and conducting laboratory tests. The study aims to gather information on the long-term effects of zasocitinib to better understand its safety and effectiveness in treating Ulcerative Colitis and Crohn's Disease.

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

    Joining the trial

    Upon joining the trial, you will be required to provide written consent. This involves signing a document that confirms your understanding of the trial procedures and your agreement to participate.

    You will also need to confirm that you meet the eligibility criteria, which includes having completed a previous related trial and meeting specific health conditions.

  2. Step 2

    Medication administration

    You will be taking an oral medication called zasocitinib. This medication comes in the form of a capsule.

    The dosage and frequency of taking zasocitinib will be determined by the trial team and communicated to you. The treatment is planned to last for up to 108 weeks.

  3. Step 3

    Regular health assessments

    Throughout the trial, you will undergo regular health assessments. These assessments will monitor your response to the medication and check for any side effects.

    The assessments will include checking vital signs, laboratory tests, and possibly electrocardiograms to ensure your safety during the trial.

  4. Step 4

    Reporting symptoms

    You will be asked to report any symptoms or changes in your health using a digital diary. This helps the trial team track your progress and any potential side effects.

    It is important to provide accurate and timely information in the diary to assist in evaluating the medication's effectiveness and safety.

  5. Step 5

    End of trial

    At the end of the trial, which is expected to last until December 2029, you will have a final assessment to evaluate your overall health and the long-term effects of the medication.

    You will receive guidance on any necessary follow-up care or additional treatments based on the results of the trial.

Who can join the trial?

6 criteria

  • The participant is willing and able to understand and fully comply with trial procedures and requirements, including digital tools and applications, as determined by the investigator. The participant has provided informed consent, which means they have signed and dated a form agreeing to participate in the trial.
  • The participant has completed Week 52 in the parent phase 2 trials for Crohn's Disease (CD) or Ulcerative Colitis (UC) with valid electronic diary data for Week 52. If this data is not available, previous scores may be used after consulting with the medical monitor.
  • The participant is a clinical or symptomatic responder at Week 52 of the parent trial. This means:
    • For Crohn's Disease: There is a 30% or more decrease in average daily very soft or liquid stools and/or a decrease in average abdominal pain from the start of the parent trial.
    • For Ulcerative Colitis: There is a reduction in the partial Mayo Score (a measure of disease activity) by 1 point or more and 30% or more from the start of the parent trial, and a decrease in rectal bleeding score by 1 point or more or an absolute rectal bleeding score of 1 point or less.
    • Participants are nonpregnant, nonlactating, or of nonchildbearing potential. For those who can have children and are sexually active, they must agree to use effective birth control during the trial and for 10 days after the last dose of the trial medication. This includes:
      • For males: Use of a male condom from the time of signing the informed consent throughout the trial and for 10 days after the last dose.
      • For females: They must be surgically sterile, postmenopausal (confirmed by a specific hormone level), or if sexually active with a nonsterilized partner, agree to use a highly effective method of contraception during the trial and for 10 days after the last dose.

Who cannot join the trial?

9 criteria

  • Patients who have not shown a response to treatment by Week 52 in the previous phase 2 trials cannot participate.
  • Patients with any other serious health conditions that might interfere with the study cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate.
  • Patients who have a history of severe allergic reactions to similar medications cannot participate.
  • Patients who are currently participating in another clinical trial cannot participate.
  • Patients who have a history of substance abuse that could affect their ability to follow the study procedures cannot participate.
  • Patients with certain infections that are not well controlled cannot participate.
  • Patients who have had recent major surgery or are planning to have surgery during the study period cannot participate.
  • Patients who have received certain treatments that might interfere with the study medication cannot participate.
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Investigated drugs

Zasocitinib is a medication being studied for its potential to help people with moderately to severely active Crohn's Disease and Ulcerative Colitis. These are conditions where the immune system mistakenly attacks the digestive tract, causing inflammation and discomfort. Zasocitinib is taken by mouth and works by targeting specific pathways in the immune system to reduce inflammation and help manage symptoms. The trial aims to see if taking Zasocitinib over a long period is safe and well-tolerated by participants who have shown improvement in earlier stages of the study.

What is already known about the treatment

Zasocitinib – Zasocitinib is an oral medication currently being studied for its long-term safety and tolerability in treating people with moderate to severely active ulcerative colitis and Crohn's disease. It is in the clinical trial phase, specifically a Phase 2 open-label extension trial, which means it is still being tested and is not yet widely available in medical practice. The main therapeutic use of zasocitinib is to help manage symptoms and improve the quality of life for individuals with these inflammatory bowel diseases. At the molecular level, zasocitinib works by targeting specific pathways in the immune system to reduce inflammation in the gut. It is classified pharmacologically as a small molecule inhibitor, which means it interferes with certain cellular processes to achieve its effects.

Investigated diseases

  • Ulcerative Colitis

    Ulcerative colitis is a chronic inflammatory condition affecting the colon and rectum. It begins with inflammation in the innermost lining of the large intestine, leading to ulcers and sores. The disease progresses with symptoms such as abdominal pain, diarrhea, and rectal bleeding. Over time, the inflammation can spread continuously throughout the colon. The severity of symptoms can vary, with periods of exacerbation and remission. As the disease advances, it can lead to complications like severe bleeding or perforation of the colon.

  • Crohn's Disease

    Crohn's disease is a chronic inflammatory disorder that can affect any part of the gastrointestinal tract, from the mouth to the anus. It typically begins with inflammation in the intestinal wall, leading to symptoms such as abdominal pain, diarrhea, and weight loss. The disease progresses with the development of deep ulcers and thickening of the intestinal wall. Unlike ulcerative colitis, Crohn's disease can cause patchy areas of inflammation, leaving some sections of the intestine unaffected. Over time, complications such as strictures, fistulas, and malnutrition may occur. The course of the disease is marked by periods of active symptoms and remission.

Trial detailsLast updated 4 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-518914-18-00Protocol codeTAK-279-IBD-2001Estimated enrolment282 patientsSponsorTakeda Development Center Americas Inc.

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