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Study of Tulisokibart for Patients with Moderately to Severely Active Ulcerative Colitis

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 a condition called Ulcerative Colitis, which is a chronic disease that causes inflammation and sores in the digestive tract, specifically affecting the colon and rectum. The study is testing a new treatment called PRA023 to see how safe and effective it is for people with moderate to severe forms of this condition. The treatment will be compared to a placebo to understand its effects better.

The purpose of the study is to evaluate the safety and tolerability of PRA023 over a 12-week period. Participants will receive the treatment through an intravenous infusion, which means the medication is given directly into a vein. The study will monitor how well the treatment works in helping patients achieve clinical remission, which means a reduction in symptoms and inflammation, by the end of the 12 weeks.

Throughout the study, participants will be closely observed for any side effects or changes in their condition. The goal is to determine if PRA023 can help improve the quality of life for those living with Ulcerative Colitis by reducing symptoms and promoting healing in the colon. This research is important for finding new and effective treatments for this challenging condition.

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 study

    Upon joining the study, the participant will be informed about the trial's purpose and procedures. Written consent is required to confirm understanding and agreement to participate.

  2. Step 2

    Initial assessment

    An initial assessment will be conducted to confirm eligibility. This includes verifying a diagnosis of ulcerative colitis and ensuring the participant meets specific health criteria.

  3. Step 3

    Treatment phase

    The treatment phase involves receiving the study medication, PRA023, or a placebo. The medication is administered through an intravenous infusion.

    Participants will receive the treatment over a period of 12 weeks. The frequency and dosage will be determined by the study protocol.

  4. Step 4

    Monitoring and follow-up

    Throughout the study, participants will undergo regular monitoring to assess the medication's effects and any side effects. This includes clinical evaluations and laboratory tests.

    Participants will be required to attend scheduled visits to track progress and ensure safety.

  5. Step 5

    Completion of the study

    At the end of the 12-week treatment period, a final assessment will be conducted to evaluate the overall impact of the treatment.

    Participants will be informed of the study's findings and any further steps if necessary.

Who can join the trial?

11 criteria

  • Must be a male or female who is 18 years of age or older.
  • Must have been diagnosed with **Ulcerative Colitis (UC)** at least 3 months before the screening. This diagnosis should be confirmed by a procedure called **endoscopy** (a test that looks inside the body) and **histology** (examining tissue under a microscope). If there is no previous confirmation, the diagnosis must be confirmed during a screening procedure called a **colonoscopy**.
  • Must have **moderately to severely active UC**. This is determined by a score called the **Modified Mayo score**, which looks at rectal bleeding, stool frequency, and endoscopy results. The score should be between 4 and 9, with specific scores for endoscopy and rectal bleeding.
  • Must meet at least one of the following treatment criteria:
    • In the past, had an inadequate response to certain treatments like **oral prednisone**, **budesonide**, **beclomethasone**, **immunosuppressants** (such as azathioprine or 6-mercaptopurine), **anti-TNF agents**, **vedolizumab**, **JAK inhibitors**, **anti-IL-12/23**, or **S1PR modulators**.
    • Had been intolerant to one or more of these treatments due to side effects.
    • Currently receiving certain treatments like oral prednisone or immunosuppressants.
    • Women who can become pregnant must use two highly effective methods of **contraception** (birth control) for at least 4 weeks before starting the study and continue until at least 12 weeks after the last dose of the study drug.
    • Men must use two highly effective methods of contraception with their female partner who can become pregnant and must not donate sperm from the screening to 12 weeks after the last dose of the study drug.
    • Must meet drug stabilization requirements, meaning certain medications should be at a stable dose for a specific period before starting the study.
    • Must be able to provide written **informed consent**, which means agreeing to participate in the study after understanding what it involves.
    • For a specific group in the study (Cohort 2), subjects must be **CDx+** (a specific requirement for that group).

Who cannot join the trial?

8 criteria

  • Patients who have a different condition than Ulcerative Colitis cannot participate. Ulcerative Colitis is a condition where the lining of the large intestine becomes inflamed.
  • Patients who are not within the specified age range cannot participate. The age range for this study is not specified here, but it is important to be within the required age group.
  • Patients who are not able to follow the study procedures or take the study medication as required cannot participate.
  • Patients who have other health conditions that might interfere with the study or put them at risk cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate.
  • Patients who have participated in another clinical trial recently may not be eligible.
  • Patients who have allergies or reactions to the study medication or similar medications cannot participate.
  • Patients who are unable to provide informed consent, which means they cannot understand the study and agree to participate, cannot participate.
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Investigated drugs

PRA023 is a medication being studied for its potential to help people with moderately to severely active ulcerative colitis. The trial aims to see if PRA023 can safely and effectively reduce the symptoms of ulcerative colitis over a 12-week period. The study will also look at how the body processes the medication. Participants will receive PRA023 to see if it can help them achieve clinical remission, which means a significant reduction or disappearance of symptoms.

What is already known about the treatment

PRA023 – PRA023 is administered as an intravenous infusion, typically given in a clinical setting. It is currently being studied in clinical trials for its potential use in treating moderately to severely active ulcerative colitis. The main therapeutic indication for PRA023 is to help induce clinical remission in patients with this condition. At the molecular level, PRA023 works by targeting specific pathways involved in inflammation, aiming to reduce the immune response that contributes to the symptoms of ulcerative colitis. It is classified pharmacologically as a monoclonal antibody, which is a type of biologic therapy designed to interfere with specific molecules in the body.

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, leading to symptoms such as abdominal pain, diarrhea, and rectal bleeding. The disease often begins gradually and can become more severe over time, with periods of exacerbation and remission. The inflammation typically starts in the rectum and can extend to involve the entire colon. The exact cause of ulcerative colitis is unknown, but it is believed to involve an abnormal immune response in the gut. Environmental factors, genetics, and an imbalance in gut bacteria may also play a role in its development.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-509741-12-00Protocol codePR200-102Estimated enrolment75 patientsSponsorPrometheus Biosciences Inc.

sourced from the EU Clinical Trials Register and site verification

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