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Study on Gene Therapy with AAV9.LAMP2B for Male Patients with Danon Disease

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 Danon Disease, a rare genetic disorder that affects the heart and other parts of the body. The study will use a treatment called RP-A501, which is a type of gene therapy. This therapy involves using a virus, specifically the Adeno-Associated Virus Serotype 9, to deliver a healthy version of a gene known as LAMP2B into the body. The goal is to see if this treatment can improve heart function in male patients with Danon Disease.

The purpose of the study is to evaluate the effectiveness and safety of the RP-A501 treatment. Participants will receive the treatment through an intravenous infusion, which means it will be delivered directly into the bloodstream. The study will monitor how well the treatment works by looking at specific markers in the heart tissue and measuring changes in heart size and function. The study will also track any side effects or safety concerns that may arise during the treatment period.

Throughout the study, participants will undergo regular check-ups and tests to assess their heart health and overall well-being. The study aims to provide valuable information on whether RP-A501 can be a beneficial treatment option for those with Danon Disease, potentially leading to improved quality of life and better management of the condition. The study is expected to continue for several years to gather comprehensive data on the treatment's long-term effects.

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

    Initial assessment

    Upon joining the study, you will undergo an initial assessment to confirm eligibility. This includes verifying a genetic variant of the LAMP2 gene and checking heart function through tests like echocardiograms.

    Your medical history will be reviewed to ensure you meet the criteria, such as being male, aged 8 years or older, and having specific heart characteristics.

  2. Step 2

    Baseline evaluations

    Before receiving the treatment, baseline evaluations will be conducted. These may include blood tests, heart imaging, and other assessments to establish your current health status.

    These evaluations help in measuring the effectiveness of the treatment over time.

  3. Step 3

    Treatment administration

    You will receive the gene therapy treatment, RP-A501, through an intravenous infusion. This involves administering the therapy directly into your bloodstream.

    The infusion process will be monitored by healthcare professionals to ensure safety and manage any immediate reactions.

  4. Step 4

    Post-treatment monitoring

    After the treatment, you will be closely monitored for any side effects or changes in your health. This includes regular follow-up visits and tests to track your heart function and overall well-being.

    Monitoring will continue for the duration of the study to assess the long-term effects and safety of the treatment.

  5. Step 5

    Ongoing evaluations

    Throughout the study, you will undergo periodic evaluations to measure the expression of the LAMP2 protein and changes in heart structure and function.

    These evaluations help determine the effectiveness of the treatment in improving your condition.

  6. Step 6

    Study completion

    At the end of the study period, a final assessment will be conducted to evaluate the overall impact of the treatment on your health.

    Results from the study will contribute to understanding the potential benefits and risks of the gene therapy for Danon Disease.

Who can join the trial?

9 criteria

  • Must have a documented change in the LAMP2 gene that is known to cause or likely to cause Danon Disease.
  • Must be male.
  • Must be 8 years old or older.
  • Must show signs of left ventricular hypertrophy (thickening of the heart muscle) with normal heart pumping function. This is defined as:
    • For those under 18 years old, a heart muscle thickness z-score of 2 or more.
    • For those 18 years or older, a heart muscle thickness greater than 13 mm, or greater than 12 mm if there is a family history of significant Danon Disease.
    • A left ventricular ejection fraction (LVEF) of 50% or more, which means the heart is pumping well.
    • Must be in New York Heart Association (NYHA) Class II to III, which means experiencing mild to moderate limitations in physical activity due to heart symptoms.
    • Must have a high-sensitivity troponin I (hsTnI) level that is 20% above the upper limit of normal, indicating some heart stress or damage.
    • Must be able to follow the study procedures, including receiving the treatment and attending follow-up visits.

Who cannot join the trial?

3 criteria

  • Patients who do not have **Danon Disease** cannot participate.
  • Only **male** patients are eligible for the study.
  • Patients who are part of a **vulnerable population** may not be eligible. This means groups of people who might be at higher risk of harm or exploitation.
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Investigated drugs

RP-A501 is a type of gene therapy being tested in this clinical trial. It uses a special virus called Adeno-Associated Virus Serotype 9, or AAV9 for short, to deliver a healthy version of a gene into the body. This gene is called LAMP2B, and it is important for the proper functioning of heart cells. In people with Danon Disease, this gene doesn't work correctly, which can lead to heart problems. The goal of this therapy is to introduce the correct version of the LAMP2B gene into the patient's heart cells, helping them to work better and potentially improving heart health.

What is already known about the treatment

RP-A501 – RP-A501 is a gene therapy medication administered intravenously, meaning it is given directly into the bloodstream through a vein. It is currently being studied in clinical trials for its potential to treat Danon Disease, a rare genetic disorder. The main goal of this therapy is to improve heart function by delivering a specific gene, LAMP2B, to the patient's cells using a virus called Adeno-Associated Virus Serotype 9 (AAV9) as a carrier. This gene therapy works at the molecular level by providing the correct version of the LAMP2B gene, which is missing or faulty in people with Danon Disease, thereby helping the heart cells function properly. RP-A501 falls under the pharmacological classification of gene therapy products.

Investigated diseases

Danon Disease – Danon Disease is a genetic disorder characterized by the buildup of autophagic vacuoles in muscle cells due to a deficiency of the LAMP2 protein. This condition primarily affects the heart, skeletal muscles, and sometimes the eyes and brain. In the heart, it leads to cardiomyopathy, which is a disease of the heart muscle that can cause it to become enlarged, thick, or rigid. As the disease progresses, individuals may experience muscle weakness and fatigue due to the involvement of skeletal muscles. The condition can also affect the electrical system of the heart, leading to arrhythmias. In some cases, intellectual disabilities or learning difficulties may occur if the brain is affected.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-506480-34-00Protocol codeRP-A501-0123Estimated enrolment16 patientsSponsorRocket Pharmaceuticals Inc.

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