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Study of Leniolisib for Children Aged 4 to 11 with Activated PI3K Delta Syndrome

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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 condition called Activated Phosphoinositide 3-Kinase Delta Syndrome (APDS), which affects the immune system. The study involves children aged 4 to 11 years who have this condition. The treatment being tested is a medication called Leniolisib, which is taken as a film-coated tablet. The purpose of the study is to evaluate the safety and effectiveness of Leniolisib in treating children with APDS.

The study is divided into two parts. In the first part, children will receive Leniolisib for a period of 12 weeks. During this time, researchers will monitor the children's health to see how well they tolerate the medication and if it helps reduce symptoms of APDS. This includes checking for any side effects and changes in their health through regular medical tests. In the second part, the study will continue to observe the long-term safety of Leniolisib in these children.

Throughout the study, children will have regular check-ups, including physical exams and tests like magnetic resonance imaging (MRI) to assess changes in their condition. The study aims to provide valuable information on how Leniolisib can help manage APDS in young patients, potentially improving their quality of life by reducing symptoms and preventing complications associated with the syndrome.

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

    Joining the study

    Upon joining the study, the patient will be assessed to ensure they meet the eligibility criteria. This includes being between 4 to 11 years old, having a confirmed genetic mutation related to APDS, and being able to take the medication without difficulty.

  2. Step 2

    Initial assessment

    The initial assessment involves checking vital signs, such as blood pressure and heart rate, and conducting a physical examination. Baseline measurements for laboratory tests, including blood and urine tests, will be taken.

  3. Step 3

    Medication administration

    The patient will begin taking leniolisib in the form of a film-coated tablet. The medication is taken orally. The dosage and frequency will be determined by the study protocol and the patient's specific needs.

  4. Step 4

    Treatment period

    The treatment period lasts for 12 weeks. During this time, the patient will continue taking the medication as prescribed. Regular monitoring will occur to assess the patient's response to the treatment and any side effects.

  5. Step 5

    Follow-up assessments

    Throughout the treatment period, follow-up assessments will be conducted. These include physical examinations, laboratory tests, and imaging studies like MRI or CT scans to evaluate changes in lymphoproliferation and other health indicators.

  6. Step 6

    Long-term extension

    After the initial 12-week treatment period, the patient may enter a long-term extension phase. This phase focuses on assessing the long-term safety and effectiveness of the medication.

  7. Step 7

    Final evaluation

    At the end of the study, a final evaluation will be conducted. This includes a comprehensive review of the patient's health, any changes in their condition, and the overall impact of the treatment.

Who can join the trial?

12 criteria

  • The patient must be a boy or girl between 4 to 11 years old at the start of the study.
  • The patient's parent or legal guardian must agree that the patient will not join any other study while in this one.
  • Girls should not be able to have children at the start of the study. Boys with partners who can have children should agree to use a very effective method to prevent pregnancy for at least 30 days after the study ends if there is a risk of pregnancy.
  • If a girl starts having periods after the study begins, she and her parent or guardian must agree to either not engage in sexual activity or use a very effective method to prevent pregnancy for at least 30 days after the study ends if there is a risk of pregnancy.
  • The patient must weigh at least 13 kg but less than 45 kg at the start of the study.
  • The patient must have a confirmed genetic change in the PI3Kδ gene, either PIK3CD (APDS1) or PIK3R1 (APDS2).
  • The patient must have at least one measurable swollen lymph node seen on a special scan within 6 months before the study starts.
  • The patient must have swelling of lymph nodes or other tissues and symptoms that match APDS, like repeated ear, nose, or lung infections or organ problems.
  • The patient must be able to swallow the study medicine without any changes, according to the doctor's opinion.
  • At the start of the study, the patient's vital signs, like blood pressure and heart rate, will be checked while sitting after resting for at least 3 minutes. These should be within normal ranges for their age, sex, and height.
  • Written permission and agreement to join the study must be obtained from the patient and their parent or guardian before any study activities begin, following national and local rules.
  • The patient's parent or guardian must be willing and able to complete the permission process and follow the study procedures and visit schedule.

Who cannot join the trial?

8 criteria

  • Patients who are not between the ages of 4 to 11 years old.
  • Patients who do not have a condition called **Activated Phosphoinositide 3-Kinase Delta Syndrome (APDS)**.
  • Patients who are not able to safely take the study medication, **leniolisib**.
  • Patients who have other medical conditions that might interfere with the study.
  • Patients who are taking other medications that might interfere with the study medication.
  • Patients who are unable to follow the study procedures or attend study visits.
  • Patients who have participated in another clinical trial recently.
  • Patients who are pregnant or breastfeeding.
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Investigated drugs

Leniolisib is a medication being studied for its safety, effectiveness, and how it behaves in the body in children aged 4 to 11 years with a condition called Activated Phosphoinositide 3-Kinase Delta Syndrome (APDS). This condition affects the immune system, and the medication aims to help manage the symptoms and improve the health of these patients. The study is designed to see how well children tolerate the medication and to monitor any side effects over a long period.

What is already known about the treatment

Leniolisib – Leniolisib is administered orally and is currently being studied in clinical trials for its safety, pharmacokinetics, pharmacodynamics, and efficacy in treating pediatric patients with Activated Phosphoinositide 3-Kinase Delta Syndrome (APDS). This medication is in the investigational stage, with ongoing research to determine its long-term safety and effectiveness. It is primarily indicated for APDS, a rare immune disorder. Leniolisib works by inhibiting the phosphoinositide 3-kinase delta (PI3Kδ) enzyme, which plays a role in immune cell function. It is classified as a selective PI3Kδ inhibitor, aiming to correct the immune system abnormalities associated with APDS.

Investigated diseases

Activated Phosphoinositide 3-Kinase Delta Syndrome – This is a rare genetic disorder that affects the immune system, leading to problems with immune cell function. It is caused by mutations in the PIK3CD gene, which results in overactive signaling in certain immune cells. Individuals with this syndrome often experience recurrent infections, particularly in the respiratory tract, due to impaired immune responses. The condition can also lead to lymphoproliferation, where there is an abnormal increase in the number of lymphocytes, a type of white blood cell. Over time, this can cause enlargement of lymph nodes, spleen, and other organs. The syndrome may also affect the development and function of B cells, which are crucial for producing antibodies.
Trial detailsLast updated 2 Oct 2026
Age0-17PhasePhase IIITrial ID2024-515489-15-00Protocol codeLE 3301Estimated enrolment21 patientsSponsorPharming Technologies B.V.

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