Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

RecruitingRare disease

Study of oral rilzabrutinib for adults with immune thrombocytopenia who did not respond to first-line treatment

Verified siteInvestigationalNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

A plain-language summary of the goals, design and what participants do

This study focuses on people with immune thrombocytopenia (ITP), a condition where the immune system mistakenly attacks and destroys blood platelets, leading to low platelet counts and increased risk of bleeding. The study will test a medication called rilzabrutinib, which is taken by mouth in tablet form, in adults whose ITP has not improved with initial treatments such as corticosteroids or immunoglobulins.

The purpose of this research is to determine if rilzabrutinib can help maintain higher platelet counts over an extended period in people with ITP. During the study, participants will take rilzabrutinib tablets daily for approximately 80 weeks. The maximum daily dose will be 800 mg.

Throughout the study, participants will have their platelet counts checked regularly to monitor how well the treatment is working. The study will also look at whether the treatment can reduce bleeding problems and allow participants to decrease or stop their corticosteroid medications. Participants' blood will be tested to check their overall health, including liver and kidney function.

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

    Initial visit and medication start

    You will begin taking rilzabrutinib tablets orally. This medication is being tested for immune thrombocytopenia (ITP), a condition affecting blood platelet levels.

    Your initial platelet count will be measured to establish a baseline.

  2. Step 2

    Regular monitoring - First 4 weeks

    Your platelet count will be checked regularly to monitor for response to treatment.

    A positive response is indicated by achieving a platelet count of at least 50,000/μL, or between 30,000/μL and 50,000/μL with at least double your starting count.

    These measurements must be recorded at least 5 days apart.

  3. Step 3

    Ongoing monitoring - Through week 28

    Platelet counts will continue to be checked every 2 weeks.

    Your bleeding symptoms will be evaluated using a standardized scale.

    If you are taking corticosteroids, your dose may be adjusted based on your response to treatment.

  4. Step 4

    Final evaluation period - Last 12 weeks

    During the final 12 weeks, you must maintain the target platelet levels for at least half of your scheduled check-ups.

    A minimum of 4 valid visits showing maintained platelet counts is required.

    Your response will be considered successful if you maintain these levels without requiring emergency treatment.

  5. Step 5

    Study completion

    The study will evaluate if the medication provided a lasting increase in your platelet count.

    Final assessments will include blood tests and evaluation of any changes in bleeding symptoms.

    Your corticosteroid use will be reviewed to determine if the dose was reduced by 50% or to less than 5 mg.

Who can join the trial?

13 criteria

  • Must be 18 years or older when signing the consent form
  • Must have confirmed diagnosis of primary immune thrombocytopenia (ITP) - a condition where the immune system attacks blood platelets
  • Must have an ECOG performance status of 2 or lower - meaning able to carry out most daily activities with minimal assistance
  • Must have received at least one first-line therapy such as corticosteroids, intravenous immunoglobulin, or anti-D treatment
  • Must have shown improvement in platelet count (above 30,000 per microliter) during previous treatment
  • Must have up-to-date vaccinations according to local guidelines
  • Must use appropriate contraception methods if sexually active
  • Must have adequate blood test results showing:
    • Hemoglobin above 9 g/dL
    • Adequate white blood cell count
    • Normal liver function tests
    • Normal kidney function
    • Normal blood clotting tests
    • Must be able to understand and sign the informed consent form

Who cannot join the trial?

15 criteria

  • Age below 18 years or above 65 years
  • Currently pregnant or breastfeeding women
  • History of blood clots or thrombotic events (formation of blood clots in blood vessels)
  • Active bleeding or high risk of bleeding
  • Recent major surgery within the last 30 days
  • Current participation in other clinical trials
  • Severe liver problems or abnormal liver function tests
  • Severe kidney problems or impaired kidney function
  • History of cancer in the past 5 years
  • Uncontrolled high blood pressure
  • Heart problems including heart failure (when heart cannot pump blood effectively)
  • Active infections including hepatitis B, hepatitis C, or HIV
  • History of autoimmune disorders (conditions where immune system attacks healthy cells) other than ITP
  • Regular use of blood thinners or anticoagulation medications
  • Alcohol or substance abuse within the past year
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

RecruitingNot yet recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

Rilzabrutinib is an oral medication that works by targeting specific proteins in the body that are involved in the immune system's response. It is being studied as a treatment for immune thrombocytopenia (ITP), a condition where the immune system mistakenly attacks and destroys platelets in the blood. This medication aims to help maintain healthy platelet levels in patients who haven't responded well to their first treatment for ITP. It comes in tablet form that patients can take by mouth.

What is already known about the treatment

Rilzabrutinib – An oral medication administered in tablet form that belongs to the class of Bruton's tyrosine kinase (BTK) inhibitors, currently being investigated in clinical trials for the treatment of immune thrombocytopenia (ITP). This drug works by blocking specific enzymes involved in the immune system's response, helping to prevent the destruction of platelets that occurs in ITP patients. Rilzabrutinib represents a novel approach to treating ITP, particularly for patients who haven't responded well to first-line treatments, and aims to provide a sustained increase in platelet counts through its targeted mechanism of action.

Investigated diseases

Immune Thrombocytopenia (ITP) - A blood disorder where the immune system mistakenly attacks and destroys platelets, which are blood cells needed for normal blood clotting. The condition causes lower than normal platelet counts in the blood, which can affect the body's ability to control bleeding. ITP can develop suddenly or gradually, and it may occur after a viral infection or without any obvious trigger. The condition can affect both children and adults, though it often presents differently in each age group. People with ITP may experience symptoms such as easy bruising, small red or purple spots on the skin called petechiae, and prolonged bleeding from minor cuts.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2025-522070-36-00Protocol codeLPS18573Estimated enrolment60 patientsSponsorSanofi-Aventis Recherche & Developpement

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.