Gene therapy aims to fix heart damage in danon disease

NCT ID NCT03882437

What the study statuses mean

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Recruitment status, easiest to join first

Recruiting now
This trial is taking on new participants right now.
Not yet recruiting
Registered, but not yet taking participants.
By invitation only
Not open to general applications. Only people the study team invites can take part.
Paused
Paused for now. It may or may not start again.
Ongoing
Running, but no longer taking on new participants.
Completed This study
The trial has finished. Results may not be published yet.
Stopped early
Stopped early, before it reached the end. That can be for many reasons, including safety.
Cancelled
Cancelled before anyone took part.

Expanded access (not trials)

Expanded access
Not a trial. This treatment can be requested outside a study, case by case, for people who qualify.
Expanded access (paused)
Not a trial. The treatment can normally be requested outside a study, but is unavailable right now.
Expanded access (ended)
Not a trial. The treatment could once be requested outside a study, but no longer can.
Approved
The treatment has been approved, so it is available normally rather than through this programme.

When the status isn't known

Details not published
The full record has not been published yet, so there is little to show here.
Status unknown
This status has not been confirmed recently, so it may be out of date.

First seen Oct 06, 2026 · Last updated Oct 07, 2026 · Updated 1 time

Summary

Researchers test a gene therapy called RP-A501 in males with Danon Disease, a rare genetic heart condition. The therapy uses a modified virus to deliver a working copy of the LAMP2B gene. The trial checks safety and whether the treatment can correct heart muscle damage and stabilize heart function.

What this could mean

Our plain-language read of the trial. This is informational only, not medical advice or a prediction.

Active substance
RP-A501, a gene therapy that delivers the LAMP2B gene using a modified virus
What this could lead to
If it works, this could offer a one-time treatment that corrects the underlying cause of Danon Disease and stabilizes heart damage.
What could go wrong
This is a very small, early-stage trial. The therapy may cause serious immune reactions or fail to improve heart function, and it is only tested in males.

This is an AI summary of the original study and may miss details. Read our disclaimer.

Study facts

What this study's own registry entry says, in plain language.

Phase

Phase 1

The first testing in people. Mainly checks safety and dose, usually in a small group.

Participants

7 people

The number who actually took part.

Started

Apr 2019

Finished

Jul 2025

Lead sponsor

A company

The lead sponsor is a pharmaceutical, biotech, or medical-device company.

Who can take part

This study's own entry requirements. Only the study team can say for certain whether you qualify.

Ages

8 years and older

Sex

Male participants only

Healthy volunteers

Not accepted

This study is not open to healthy volunteers. The entry requirements below say who it is open to.

Show the full entry requirements

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Main Criteria for Inclusion: The study will enroll adult and pediatric males with a confirmed diagnosis of DD. Patients may be of any race or ethnicity. Patients and/or competent custodial parents must provide informed written consent and meet all of the enrollment criteria as detailed subsequently to be eligible to participate. 1. DD diagnosis with any confirmed LAMP2 mutation(s). 2. Cardiac involvement as documented by at least one abnormal finding on electrocardiogram (ECG), echocardiogram, gadolinium-enhanced cardiac magnetic resonance imaging (MRI), or electrophysiology study. 3. Age ≥15 years for cohorts 1 and 2; 8-14 years for cohorts 1A. 4. Male gender. 5. New York Heart Association (NYHA) Class II or III. 6. Adequate hematologic function as defined by hemoglobin, absolute neutrophil count (ANC), and platelet count ≥ lower limit of normal (LLN). 7. Adequate hepatic function as defined by: 1. AST and ALT ≤10.0×ULN or GGT ≤2.0×ULN (transaminase elevations in DD are considered extensively to result from muscle injury; hence the relatively high upper limit for transaminases and consideration of GGT level, and the presence of additional hepatic eligibility markers of bilirubin and PT/INR). 2. Serum bilirubin ≤1.2×ULN (i.e., Grade ≤1 bilirubin increase). 3. PT/INR ≤1.2×ULN (in the absence of anticoagulation). 4. Absence of cirrhosis or other signs of inflammation on liver ultrasound 8. Adequate renal function as defined by creatinine ≤ULN. 9. Ability to provide informed consent (for adult patients and parents/legal guardians of pediatric patients) and assent (for patients age 15-17). 10. Ability to comply with study procedures including investigational therapy and follow-up evaluations. 11. Able to walk \>150 meters unassisted during the 6MWT. 12. Patient has received meningococcal vaccination recommended by Centers for Disease Control as appropriate for age and health condition (vaccination must be performed at least 6 weeks prior to IP administration). Main Criteria of Exclusion: Patients meeting any of the following criteria are not eligible for study participation: 1. I.V. therapy with positive inotropes, vasodilators, or diuretics within the 30 days prior to enrollment (i.e., patient must be stable on oral medical therapy). 2. Prior cardiac transplantation or prior transplant of other organ (lung, liver, other). 3. Prior cardiac surgery and/or percutaneous cardiac intervention for arteriothrombotic complications, or valvuloplasty. 4. Presence or requirement of a Left Ventricular Assisted Device (LVAD). 5. History of intracardiac thrombosis or arteriothromboembolic events including stroke or transient ischemic attack (TIA). 6. Left ventricular ejection fraction (LVEF) \<40% at baseline. 7. History of the following prior arteriothromboembolic complications: myocardial infarction or unstable angina. 8. Significant (greater than moderate) valvular stenosis or regurgitation on echocardiogram. 9. Requires mechanical ventilation. 10. Anti-AAV9 neutralizing antibody titer \>1:40. 11. Concurrent enrollment in any other clinical investigation involving use of an investigational agent for the treatment of CHF or cardiomyopathy. 12. Active hepatitis B or C infection (including patients with positive hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), hepatitis B core antibody (HBcAb), or detectable hepatitis B virus (HBV) or hepatitis C virus (HCV) viral load). Patients with previous, adequately resolved HBV or HCV are eligible. 13. Significant medical conditions including documented human immunodeficiency virus (HIV) infection, active viral or other hepatitis, poorly-controlled hypertension or diabetes, poorly controlled cardiac arrhythmia, or uncontrolled viral, bacterial, or fungal infection. 14. Any concomitant medical or psychiatric condition that in the opinion of the Investigator renders the patient unfit for study participation or at higher than acceptable risk for study participation. 15. Active hematologic or solid organ malignancy, not including non-melanoma skin cancer or other carcinoma in situ. Patients with previously resected solid organ malignancies or definitively treated hematologic malignancies may be eligible if there has been no evidence of active malignancy during the prior 3 years. 16. Any contraindication to use of sirolimus which includes hypersensitivity to sirolimus or HC-60 (polyoxyl 60 hydrogenated castor oil). 17. Active or latent tuberculosis.

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Conditions

The condition(s) this trial relates to.

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Locations

  • Children's Hospital of Philadelphia

    Philadelphia, Pennsylvania, 19104, United States

  • University of California, San Diego

    La Jolla, California, 92037, United States

  • University of Colorado

    Aurora, Colorado, 80045, United States

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