Gene therapy aims to fix heart damage in danon disease
NCT ID NCT03882437
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
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Phase 1
The first testing in people. Mainly checks safety and dose, usually in a small group.
- Participants
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7 people
The number who actually took part.
- Started
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Apr 2019
- Finished
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Jul 2025
- Lead sponsor
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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
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8 years and older
- Sex
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Male participants only
- Healthy volunteers
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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 Hide 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
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Children's Hospital of Philadelphia
Philadelphia, Pennsylvania, 19104, United States
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University of California, San Diego
La Jolla, California, 92037, United States
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University of Colorado
Aurora, Colorado, 80045, United States
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Other studies related to the condition(s) this trial covers.
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