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Study on the Use of OTL-103 Gene Therapy and Drug Combination for Patients with Wiskott-Aldrich Syndrome

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 rare genetic disorder known as Wiskott-Aldrich Syndrome (WAS). This condition affects the immune system and can lead to problems such as bleeding and infections. The study is testing a new treatment called OTL-103, which is a type of gene therapy. Gene therapy involves using a patient's own cells that are modified to correct the genetic defect causing the disease. In this case, the cells are treated with a special virus that carries the correct version of the gene responsible for WAS. The modified cells are then returned to the patient to help improve their immune system function.

The purpose of the study is to evaluate how effective and safe this new treatment is for people with WAS. Participants will receive the gene therapy and will be monitored for changes in their health, particularly looking at the number of bleeding events and infections they experience. The study will also involve other medications, including Busulfan, Fludarabine Phosphate, Plerixafor, Rituximab, and Lenograstim, which are used to prepare the body for the gene therapy and support the treatment process.

Throughout the study, participants will receive regular check-ups to assess their overall health and the effectiveness of the treatment. The study will last for several years, with key assessments at 12, 24, and 36 months after receiving the gene therapy. The goal is to see if the treatment can reduce the frequency of severe infections and bleeding episodes, as well as to ensure that it is safe for long-term use. Participants will be closely monitored for any side effects or complications related to the treatment.

The research process

The trial runs in 7 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes verifying the diagnosis of Wiskott-Aldrich Syndrome through genetic testing and ensuring no suitable donor is available.

  2. Step 2

    Pre-treatment preparation

    Before starting the main treatment, you will receive medications to prepare your body. This includes rituximab administered through an intravenous infusion to help manage your immune system.

    You will also receive plerixafor as a subcutaneous injection to mobilize stem cells in your blood.

  3. Step 3

    Stem cell collection

    Your stem cells will be collected from your blood. This process is known as apheresis and involves drawing blood, separating the stem cells, and returning the rest of the blood to your body.

  4. Step 4

    Gene therapy preparation

    The collected stem cells are modified in a laboratory to include a healthy copy of the gene affected by Wiskott-Aldrich Syndrome. This process uses a lentiviral vector to deliver the gene.

  5. Step 5

    Conditioning treatment

    You will receive conditioning treatment to prepare your body for the modified stem cells. This includes busulfan and fludarabine phosphate administered through intravenous infusions to reduce your immune system's activity and make space for the new cells.

  6. Step 6

    Gene therapy administration

    The modified stem cells, now called OTL-103, are administered back into your body through an intravenous infusion. This is the main part of the gene therapy treatment.

  7. Step 7

    Post-treatment monitoring

    After receiving the gene therapy, you will be closely monitored for any side effects and to assess the treatment's effectiveness. This includes regular check-ups and tests over a period of 12 to 36 months.

    You may receive lenograstim as a subcutaneous injection to help your body produce more blood cells during recovery.

Who can join the trial?

6 criteria

  • Must have a diagnosis of Wiskott-Aldrich Syndrome (WAS), which is a rare genetic disorder.
  • The diagnosis must be confirmed by a genetic mutation and at least one of the following:
    • A severe mutation in the WASP gene, which is responsible for the condition.
    • Absence of WASP protein expression, meaning the protein is not produced in the body.
    • A severe clinical score of 3 or higher, based on the Zhu clinical score, which measures the severity of the condition.
    • No available HLA-identical related donor, which means there is no family member with a matching tissue type for a potential transplant.
    • Participants must be male.

Who cannot join the trial?

3 criteria

  • Patients who do not have Wiskott-Aldrich Syndrome cannot participate.
  • Only male patients are eligible to participate.
  • Patients who are not within the specified age range cannot participate. The age range is not specified in the provided data.
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Investigated drugs

OTL-103 is a type of gene therapy used in this clinical trial. It involves taking a patient's own stem cells, which are special cells that can develop into different types of blood cells. These stem cells are collected and then modified in a laboratory using a lentiviral vector, which is a tool that helps deliver new genetic material into the cells. The new genetic material includes a healthy version of the WAS gene, which is important for people with Wiskott-Aldrich Syndrome, a condition that affects the immune system and blood clotting. After the modification, the cells are frozen and later given back to the patient. The goal of this therapy is to help the patient's body produce healthy blood cells that can reduce bleeding events and severe infections.

What is already known about the treatment

OTL-103 – OTL-103 is administered as a gene therapy treatment using cryopreserved autologous CD34+ cells, which are stem cells collected from the patient's own blood. This therapy is currently being studied in clinical trials for its effectiveness in treating Wiskott-Aldrich Syndrome, a rare genetic disorder. The main goal of this treatment is to reduce bleeding events and severe infections by introducing a healthy copy of the WAS gene into the patient's stem cells using a lentiviral vector. OTL-103 falls under the pharmacological classification of gene therapy, which involves modifying genes to treat or prevent disease.

Investigated diseases

Wiskott-Aldrich Syndrome – Wiskott-Aldrich Syndrome is a rare genetic disorder that affects the immune system and blood clotting. It is characterized by a low number of platelets, leading to easy bruising and bleeding. Individuals with this syndrome often experience recurrent infections due to a weakened immune system. The disease progresses with symptoms such as eczema, autoimmune disorders, and an increased risk of developing certain cancers. Over time, the immune system's ability to fight infections continues to decline. The severity of symptoms can vary widely among affected individuals.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-517792-20-00Protocol codeOTL-103-4Estimated enrolment10 patientsSponsorFondazione Telethon Ets

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