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Study on the Safety of Censavudine (TPN-101) for Patients with Aicardi-Goutières Syndrome

Verified siteInvestigationalNo 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 Aicardi-Goutières Syndrome (AGS), a rare genetic disorder that affects the brain and immune system. The study is testing a new drug called TPN-101, also known as censavudine, to see if it is safe for patients with AGS. The drug is taken as a powder mixed with water to make an oral solution. The main goal of the study is to see if TPN-101 can reduce certain immune system signals in the body, which are often higher in people with AGS.

Participants in the study will receive either TPN-101 or a placebo for up to 48 weeks. During this time, researchers will monitor the safety of the drug and any side effects that may occur. They will also measure the levels of TPN-101 in the blood and cerebrospinal fluid, which is the fluid surrounding the brain and spinal cord. Additionally, the study will look at various markers in the blood and cerebrospinal fluid to understand how the drug affects the body.

Throughout the study, participants will undergo regular check-ups, including blood tests and brain scans using MRI to assess changes in brain function and structure. The study aims to gather important information about the potential benefits and risks of TPN-101 for treating AGS, which could lead to new treatment options for this challenging condition.

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

    The initial visit involves a comprehensive assessment to confirm eligibility for the study. This includes a review of medical history and a physical examination.

    Blood samples are collected to measure the interferon (IFN) score, which is a measure of certain gene expressions in the blood.

  2. Step 2

    Screening period

    The screening period lasts for approximately 8 weeks. During this time, blood samples are taken on three separate occasions, about two weeks apart, to confirm the IFN score.

    The IFN score must be higher than a specific threshold to continue in the study.

  3. Step 3

    Treatment phase

    Participants receive the study medication, TPN-101, which is administered as a powder for oral solution. The exact dosage and frequency are determined by the study protocol.

    The treatment phase lasts up to 48 weeks, during which the safety and effects of the medication are closely monitored.

  4. Step 4

    Regular assessments

    Throughout the treatment phase, regular assessments are conducted to monitor health and response to the medication.

    These assessments include blood tests to measure IFN levels and other biomarkers, as well as brain imaging and evaluations of clinical and functional status.

  5. Step 5

    End of treatment

    At the end of the treatment period, a final set of assessments is conducted to evaluate the overall impact of the medication.

    Participants may be asked to return for follow-up visits to monitor any long-term effects.

Who can join the trial?

14 criteria

  • Participants can be male or female.
  • Participants are divided into four age groups:
    • Adults: 18 years and older
    • Adolescents: 12 to 17 years old
    • Children: 5 to 11 years old
    • Children: 1 to less than 5 years old and weighing at least 10 kg
    • Participants must have a confirmed diagnosis of **Aicardi-Goutières Syndrome (AGS)**, which is a genetic condition. This diagnosis is based on specific changes (mutations) in certain genes.
    • Participants must have a high **interferon (IFN) score** in their blood. This score is a measure of certain genes' activity related to the immune system, and it must be higher than normal levels.
    • Participants should show symptoms that match an AGS diagnosis. These symptoms can include:
      • Early brain problems with delayed movement and growth, muscle stiffness, and small head size.
      • Calcium deposits in certain brain areas.
      • Changes in brain tissue.
      • Brain shrinkage.
      • Other early symptoms like irritability, feeding and sleeping issues, unexplained fevers, and skin problems.
      • Women who can have children must either be surgically unable to have children or agree to use effective birth control methods during the study and for three months after the last dose of the study medication. Pregnant or breastfeeding women cannot participate.
      • Male participants with partners who can have children must agree to use a condom and ensure their partner uses effective birth control methods during the study and for three months after the last dose of the study medication.

Who cannot join the trial?

6 criteria

  • Patients who have a different condition than Aicardi-Goutières Syndrome (AGS) cannot participate. AGS is a rare genetic disorder.
  • Patients who are not within the specified age range for the study cannot participate. The study is open to certain age groups only.
  • Patients who are not able to follow the study procedures or who have other health conditions that might interfere with the study cannot participate.
  • Patients who are pregnant or breastfeeding cannot participate in the study.
  • Patients who are taking certain medications that might interfere with the study cannot participate.
  • Patients who have participated in another clinical trial recently may not be eligible to participate.
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Investigated drugs

TPN-101 is a medication being studied for its potential to help patients with Aicardi-Goutières Syndrome (AGS). The main goal of the trial is to see if TPN-101 can lower the interferon score, which is a measure of inflammation in the body. Researchers are also looking at how safe and tolerable TPN-101 is for patients with AGS.

What is already known about the treatment

TPN-101 – TPN-101 is administered orally and is currently being studied in clinical trials for its potential use in treating Aicardi-Goutières Syndrome (AGS). This medication is in the investigational stage, with ongoing research to establish its effectiveness and safety. The primary therapeutic indication for TPN-101 is to reduce the interferon score in patients with AGS, a rare genetic disorder. At the molecular level, TPN-101 is believed to work by modulating pathways that lead to the overproduction of interferon, which is a key factor in the symptoms of AGS. It is classified pharmacologically as an immunomodulatory agent.

Investigated diseases

Aicardi-Goutières Syndrome – Aicardi-Goutières Syndrome (AGS) is a rare genetic disorder that primarily affects the brain, immune system, and skin. It often presents in infancy or early childhood, with symptoms that may include developmental delays, neurological issues, and skin abnormalities. The disease is characterized by an inappropriate immune response, leading to inflammation in the brain and other tissues. Over time, affected individuals may experience progressive neurological decline, with varying degrees of severity. AGS is caused by mutations in specific genes that are involved in the body's immune response. The condition is inherited in an autosomal recessive pattern, meaning both copies of the gene in each cell have mutations.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-511176-32-00Protocol codeTPN-101-AGS-201Estimated enrolment52 patientsSponsorTransposon Therapeutics Inc.

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