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Study on Long-Term Safety of Tolebrutinib for Patients with Relapsing or Progressive Multiple Sclerosis

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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 Tolebrutinib in individuals with different types of Multiple Sclerosis (MS). Multiple Sclerosis is a disease that affects the nervous system, and this study includes participants with relapsing MS, primary progressive MS, and non-relapsing secondary progressive MS. The medication being tested, Tolebrutinib, is taken in the form of film-coated tablets. The study also involves the use of a placebo, which is a substance with no active medication, to compare the effects of Tolebrutinib.

The purpose of this study is to determine how safe and tolerable Tolebrutinib is over a long period. Participants will take the medication orally, and the study will last for up to 36 months. During this time, researchers will monitor participants for any adverse events, which are unwanted effects that may occur during the study. The study will also look at how the medication affects the progression of disability in participants with MS and track any changes in the brain using Magnetic Resonance Imaging (MRI), a type of scan that provides detailed images of the brain.

In addition to Tolebrutinib, the study involves other substances like Anhydrous Cholestyramine, which is used to bind certain substances in the intestines, and Magnetic Resonance Imaging Contrast Media, which helps improve the clarity of MRI images. These substances are used to support the study's objectives and ensure accurate monitoring of the participants' health. The study aims to provide valuable information on the long-term use of Tolebrutinib in managing Multiple Sclerosis.

The research process

The trial runs in 4 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, participants are required to have completed a previous Phase 2b or Phase 3 trial involving tolebrutinib. This includes those who may have temporarily discontinued due to a national emergency but completed trial visits.

  2. Step 2

    Medication administration

    Participants will receive tolebrutinib, administered as a film-coated tablet for oral use. The specific dosage and frequency will be determined by the study protocol.

  3. Step 3

    Monitoring and assessments

    Regular monitoring will occur to assess the long-term safety and tolerability of tolebrutinib. This includes tracking any adverse events, serious adverse events, and any events leading to discontinuation of the study medication.

    Participants will undergo assessments to measure disability progression and relapse rates, as well as changes in brain lesions through imaging techniques.

  4. Step 4

    Completion of study

    The study is estimated to conclude by August 30, 2029. Participants will continue to be monitored until the end of the study to ensure comprehensive data collection on the long-term effects of tolebrutinib.

Who can join the trial?

5 criteria

  • Participants must have a type of multiple sclerosis, which is a disease affecting the nervous system. This includes relapsing multiple sclerosis (RMS), primary progressive multiple sclerosis (PPMS), or non-relapsing secondary progressive multiple sclerosis (NRSPMS).
  • Participants should have completed a specific earlier study, either the Phase 2b LTS (LTS16004) or one of the four Phase 3 trials (EFC16033, EFC16034, EFC16645, EFC16035) involving the study medication.
  • Participants who had to stop the study medication temporarily due to a national emergency but completed the required trial visits can also join.
  • Both men and women are eligible to participate.
  • The study includes people from vulnerable populations, which means those who might need extra protection or care.

Who cannot join the trial?

10 criteria

  • Patients with certain nervous system diseases may not be eligible. This includes conditions that affect the brain, spinal cord, and nerves.
  • Individuals who do not meet the age requirements for the study.
  • Participants who are not able to follow the study procedures or take the study medication as required.
  • People with other medical conditions that might interfere with the study or pose a risk to their health.
  • Women who are pregnant or breastfeeding may not be able to participate.
  • Individuals who are currently participating in another clinical trial.
  • Patients who have had a recent major surgery or are planning to have surgery during the study period.
  • Anyone with a history of allergic reactions to the study medication or similar drugs.
  • People with certain infections or diseases that could affect the study results.
  • Individuals who have a history of substance abuse or are currently using illegal drugs.
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Investigated drugs

Tolebrutinib is a medication being studied for its long-term safety and tolerability in people with multiple sclerosis. This includes those with relapsing forms of the disease, as well as primary progressive and nonrelapsing secondary progressive multiple sclerosis. The goal is to see how well patients can tolerate the medication over an extended period and to monitor any potential side effects.

What is already known about the treatment

Tolebrutinib – Tolebrutinib is administered orally in the form of tablets. It is currently in a Phase 3 clinical trial, focusing on its long-term safety and tolerability for treating multiple sclerosis, including relapsing and progressive forms. The main therapeutic indication for tolebrutinib is multiple sclerosis, a disease affecting the nervous system. At the molecular level, tolebrutinib works by inhibiting Bruton's tyrosine kinase, which plays a role in the immune system's activity, potentially reducing inflammation and nerve damage. It is classified pharmacologically as a kinase inhibitor.

Investigated diseases

  • Relapsing Multiple Sclerosis

    This is a chronic disease affecting the central nervous system, characterized by episodes of new or increasing neurological symptoms. These episodes, known as relapses, are followed by periods of partial or complete recovery. Over time, the disease can lead to a gradual worsening of symptoms. The exact cause is unknown, but it involves an immune-mediated process. It primarily affects young adults and is more common in women than men. Symptoms can vary widely, including fatigue, vision problems, and muscle weakness.

  • Progressive Multiple Sclerosis

    This form of multiple sclerosis is marked by a steady progression of neurological symptoms without relapses. It can be further classified into primary progressive and secondary progressive types. In primary progressive multiple sclerosis, symptoms gradually worsen from the onset without early relapses. Secondary progressive multiple sclerosis begins with a relapsing-remitting course, which then transitions into a progressive form. The disease affects the brain and spinal cord, leading to increasing disability over time. Symptoms may include walking difficulties, muscle stiffness, and cognitive changes.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2023-503631-18-00Protocol codeLTS17043Estimated enrolment1 627 patientsSponsorSanofi-Aventis Recherche & Developpement

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