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Study on Personalized Dosing of Natalizumab for Patients with Relapsing-Remitting Multiple Sclerosis

Verified siteRegistered drugNo 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 known as relapsing-remitting multiple sclerosis, a type of multiple sclerosis where patients experience periods of new or worsening symptoms followed by periods of recovery. The study is investigating a treatment called natalizumab, which is used to help manage this condition. Natalizumab is administered in two forms: as a concentrate for solution for infusion, known as Tysabri and Tyruko, and as a solution for injection in a pre-filled syringe, also under the name Tysabri.

The purpose of the study is to explore the safety and practicality of a personalized approach to dosing natalizumab at extended intervals, starting from every six weeks. This approach is being tested in a large group of people in the Netherlands who are living with relapsing-remitting multiple sclerosis. The study will monitor participants over a period of time to see how their condition responds to this dosing schedule.

Participants in the study will receive natalizumab through either an intravenous infusion, which means the medication is given directly into a vein, or through a subcutaneous injection, which is an injection under the skin. The study will track the activity of the disease using MRI scans to look for any new or growing lesions in the brain over a two-year period. This will help researchers understand the effects of the extended dosing schedule on the disease's progression.

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

    Participation begins after meeting specific criteria: a diagnosis of relapsing remitting multiple sclerosis, having received at least six consecutive infusions of the medication natalizumab, being 18 years or older, and providing written consent.

  2. Step 2

    Initial treatment phase

    The treatment involves the administration of natalizumab, a medication used to manage multiple sclerosis. It is given as an intravenous infusion, which means it is delivered directly into a vein.

    The specific products used are Tysabri 300 mg concentrate for solution for infusion and Tyruko 300 mg concentrate for solution for infusion.

  3. Step 3

    Extended interval dosing

    The study aims to test the safety and feasibility of extending the interval between doses of natalizumab starting from every 6 weeks. This is a personalized approach, meaning the schedule may be adjusted based on individual needs.

  4. Step 4

    Alternative administration method

    In addition to intravenous infusions, natalizumab may also be administered as a subcutaneous injection, which is an injection under the skin. The product used for this method is Tysabri 150 mg solution for injection in pre-filled syringe.

  5. Step 5

    Monitoring and evaluation

    Throughout the study, the primary focus is on monitoring radiological disease activity. This involves checking for new or enlarging T2 lesions on brain MRI scans over a period of two years.

  6. Step 6

    Completion of the study

    The study is expected to conclude by July 1, 2026. The results will help determine the effectiveness and safety of the extended interval dosing strategy for natalizumab in managing multiple sclerosis.

Who can join the trial?

4 criteria

  • Have a diagnosis of relapsing remitting multiple sclerosis according to the 2017 criteria. This is a type of multiple sclerosis where symptoms come and go.
  • Have received 6 or more consecutive infusions of natalizumab. Natalizumab is a medication used to treat multiple sclerosis.
  • Be 18 years or older.
  • Have agreed to participate by providing written informed consent. This means you understand the study and agree to take part in it.
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Investigated drugs

Natalizumab is a medication used in the treatment of relapsing-remitting multiple sclerosis (RRMS). It works by blocking certain cells in the immune system from reaching the brain and spinal cord, which helps reduce inflammation and prevent relapses. In this clinical trial, the focus is on testing the safety and feasibility of extending the time between doses of natalizumab, starting from a 6-week interval, to see if it can be personalized for patients while maintaining its effectiveness.

What is already known about the treatment

Natalizumab – This medication is administered through an intravenous infusion, typically given in a healthcare setting. It is currently used in the treatment of relapsing-remitting multiple sclerosis, with ongoing research exploring personalized dosing intervals. Natalizumab works by blocking certain immune cells from crossing into the brain and spinal cord, which helps reduce inflammation and nerve damage. It is classified as a monoclonal antibody, specifically targeting the alpha-4 integrin molecule on the surface of immune cells.

Investigated diseases

Multiple Sclerosis – Multiple Sclerosis is a chronic disease that affects the central nervous system, particularly the brain and spinal cord. It occurs when the immune system mistakenly attacks the protective sheath (myelin) that covers nerve fibers, leading to communication problems between the brain and the rest of the body. Over time, the disease can cause permanent damage or deterioration of the nerves themselves. Symptoms vary widely and can include fatigue, difficulty walking, numbness or tingling, muscle weakness, and problems with coordination and balance. The progression of the disease can be unpredictable, with periods of remission and relapses. The severity and specific symptoms can differ greatly from person to person.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-513105-31-00Estimated enrolment440 patientsSponsorAmsterdam UMC Stichting

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