Danon DiseasePhase 2NCT06092034
A Gene Therapy Study of RP-A501 in Male Patients With Danon Disease
A Phase 2 study testing RP-A501 in people with Danon Disease, run by Rocket Pharmaceuticals Inc. at 6 sites in 4 countries.
Trial summary
This is a single arm Phase 2 trial to evaluate the efficacy and safety of RP-A501, a recombinant adeno-associated virus serotype 9 (rAAV9) vector containing the human lysosome-associated membrane protein 2 isoform B (LAMP2B) transgene, in male patients with Danon disease. Read more about this study
- Who is it for?
- Ages 8 years and older, men only
- Conditions the study is for
- Danon Disease
- What is being tested?
- RP-A501
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 18 participants
- Where
- 6 sitesin 4 countries
- Study dates
- 5 Sep 2023to Jun 2032
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 8 years and older
- Men only
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Documentation of a pathogenic or likely pathogenic variant of the LAMP2 gene.
- Male.
- Age ≥8 years.
- Evidence of left ventricular hypertrophy with preserved systolic function phenotype as defined by each of the following:
- Abnormal thickening of left ventricular wall,
- Left ventricular ejection fraction (LVEF) ≥ 50%.
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- New York Heart Association (NYHA) Class II to III.
- High sensitivity Troponin I (hsTnI) ≥20% above the upper limit of normal (ULN) ≤ 12 months prior to screening.
- Ability to comply with study procedures including investigational therapy and follow-up evaluations.
Who cannot join
- Anti-AAV9 neutralizing antibody titer >1:40.
- Severe heart failure or requirement for advanced therapies (requirement for intravenous inotropic, vasodilator, or diuretic therapy within the 30 days prior to enrollment, presence or requirement for mechanical circulatory support (MCS), and presence or requirement for mechanical ventilation).
- History of intracardiac thrombosis or arterial thromboembolic events including stroke, transient ischemic attack (TIA), acute coronary syndrome, myocardial infarction or unstable angina.
- Prior cardiac or other organ (lung, liver, other) transplantation.
Trial locations and contacts
6 sites in 4 countries. Contact the study team or a site near you to ask about taking part.
6 sites in 4 countries
United States3 sites, 3 recruiting
- Recruiting
Boston Children's Hospital
Boston, Massachusetts, 02115
Emily Morris, Emily.Morris@childrens.harvard.edu
Bridget Kerwin, BridgetO_Kerwin@DFCI.HARVARD.EDU
- Recruiting
University of California, San Diego
La Jolla, California, 92037
Barry Greenberg, MD, 858-246-2987, Bgreenberg@health.ucsd.edu
- Recruiting
Children's Hospital of Philadelphia
Philadelphia, Pennsylvania, 19104
Joseph Rossano, MD, rossanoj@chop.edu
Germany1 site, 1 recruiting
- Recruiting
German Heart Center Munich
Munich
Cordula Wolf, MD, wolf@dhm.mhn.de
Italy1 site, 1 recruiting
- Recruiting
Meyer Children's Hospital
Florence
Iacopo Olivotto, MD, iacopo.olivotto@unifi.it
United Kingdom1 site, 1 recruiting
- Recruiting
Great Ormond Street Hospital & UCL Institute of Cardiovascular Science
London
Juan Kaski, MD, Juan.Kaski@gosh.nhs.uk
About this study
Official title: Gene Therapy for Danon Disease: A Phase 2 Study Evaluating the Efficacy and Safety of Intravenously Administered Adeno-Associated Virus Serotype 9 (rAAV9) Vector Containing the Human LAMP2 Isoform B Transgene (RP-A501; AAV9.LAMP2B) in Male Patients With Danon Disease
This is a single arm Phase 2 trial to evaluate the efficacy and safety of RP-A501, a recombinant adeno-associated virus serotype 9 (rAAV9) vector containing the human lysosome-associated membrane protein 2 isoform B (LAMP2B) transgene, in male patients with Danon disease.
Read the detailed description
RP-A501-0123 is a Phase 2 global, multi-center, single arm, open-label, single dose trial in males with Danon disease. The study is designed to assess the efficacy and safety of a single intravenous dose of RP-A501 in treating the cardiomyopathy associated with Danon disease.
RP-A501-0123 will enroll subjects ≥ 8 years of age with a pathogenic or likely pathogenic LAMP2 variant. The trial will include a total of 5 years of follow-up after administration of RP-A501.
- Conditions
- Danon Disease
- Being tested
- RP-A501
- Keywords
- Hypertrophic Cardiomyopathy, HCM, X-linked disease, LAMP2, Pediatric, Skeletal Myopathies, Cardiomyopathy, Lysosomal Storage Disorder, Left Ventricular Hypertrophy
- Medical subject headings
- Glycogen Storage Disease Type IIb, Cardiomyopathy, Hypertrophic, Cardiomyopathies, Lysosomal Storage Diseases, Hypertrophy, Left Ventricular
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
RP-A501Genetic
RP-A501 is a gene therapy product consisting of an rAAV9 capsid containing the human LAMP2B transgene which will be administered as a single IV infusion.
Dose of RP-A501: Cohorts 1, 2 \& 3 = 6.7 x10^13 genome copies (GC)/kg; Cohort 4 = 3.8 x10^13 GC/kg.
An immunomodulation regimen is initiated before RP-A501 administration to reduce the risk of gene therapy-related complications. The regimen includes rituximab or a biosimilar, administered in two doses for Cohorts 1-3 and three doses for Cohort 4, along with sirolimus and corticosteroids. Pegcetacoplan was incorporated into the immunomodulation regimen for Cohort 3 but excluded in Cohort 4.
| Study group | Role | What they receive |
|---|---|---|
| RP-A501 | Experimental | A single intravenous infusion of RP-A501 in cohorts of subjects with a confirmed diagnosis of Danon disease. Receives: Genetic: RP-A501 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Evaluation of Efficacy: Improvement as assessed via primary endpoint comprised of LAMP2 myocardial tissue expression and left ventricular mass index (LVMI)
Myocardial tissue expression of LAMP2 protein improved from baseline to ≥ Grade 1 (by IHC), AND, ≥ 10% decrease in LVMI from baseline.
Measured: 12 months post-infusion
Secondary outcomes (8)
Evaluation of efficacy via components of the primary endpoint - LAMP2
Myocardial tissue expression of LAMP2 protein improved from baseline to ≥ Grade 1 (by IHC)
Measured: 12 months post infusion
Evaluation of efficacy via components of the primary endpoint - Left Ventricular Mass Index (LVMI)
≥ 10% decrease in LVMI from baseline
Measured: 12 months post infusion
Evaluation of efficacy via biomarker evidence of myocardial injury - High Sensitivity Troponin I (hsTnI)
≥ 20% decrease in hsTnI from baseline
Measured: 12 months post infusion
Evaluation of efficacy via biomarker evidence of myocardial injury - N-Terminal Prohormone of Brain Natriuretic Peptide (NT-proBNP)
≥ 20% decrease in NT-proBNP from baseline
Measured: 12 months post infusion
Evaluation of efficacy via Quality of Life
Change in KCCQ-12 Overall Score from baseline
Measured: 12 months post infusion
Evaluation of efficacy via heart failure symptoms
Change in NYHA class from baseline
Measured: 12 months post infusion
Evaluation of efficacy via assessment of event-free survival
- Event free survival with events defined as death, heart transplant, mechanical circulatory support (MCS) or heart failure hospitalization
- Incidence of death, heart transplant, MCS, or heart failure hospitalization
Measured: From infusion to 60 months post infusion
Evaluation of safety
Incidence, severity and duration of treatment emergent safety events.
Measured: From infusion to 60 months post infusion
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Oct 2023
- Study start5 Sep 2023
- Primary completionJun 2028 (estimated)
- Study completionJun 2032 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Danon DiseaseStudies of the same condition, open and under way.
- More trials run by Rocket Pharmaceuticals Inc.The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Cohort 1: Adolescent/Adult males (age ≥ 15 years) \[N=1 subject; enrollment closed\] Cohort 2: Pediatric males (age 8 to 14 years) \[N= 3 subjects; enrollment closed\] Cohort 3: Males age ≥ 8 years receiving a pegcetacoplan-containing immunomodulatory regimen \[N=2 subjects; enrollment closed\] Cohort 4: Males age ≥ 8 years \[N=12 subjects; enrolling\]
- Masking
- None (open label)
- Enrolment
- 18 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Rocket Pharmaceuticals Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Joseph Rossano, MD, Principal investigator, Children's Hospital of PhiladelphiaBarry Greenberg, MD, Principal investigator, University of California, San Diego
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06092034
- Sponsor's protocol ID
- RP-A501-0123
- Other IDs
- LAMPLIGHT-2
- Status last verified
- Oct 2026
- First submitted
- 11 Oct 2023
- Last updated
- 6 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Gene Therapy for Danon Disease: A Phase 2 Study Evaluating the Efficacy and Safety of Intravenously Administered Adeno-Associated Virus Serotype 9 (rAAV9) Vector Containing the Human LAMP2 Isoform B Transgene (RP-A501; AAV9.LAMP2B) in Male Patients With Danon Disease
- ClinicalTrials.gov ID
- NCT06092034
- Acronym / sponsor ID
- RP-A501-0123
- Conditions
- Danon Disease
- Keywords
- Hypertrophic Cardiomyopathy, HCM, X-linked disease, LAMP2, Pediatric, Skeletal Myopathies, Cardiomyopathy, Lysosomal Storage Disorder
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 18 participants (estimated)
- Lead sponsor
- Rocket Pharmaceuticals Inc.Industry (pharma, biotech, devices)
- Study start
- 5 Sep 2023 (actual)
- Primary completion
- Jun 2028 (estimated)
- Study completion
- Jun 2032 (estimated)
- First posted
- 23 Oct 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a single arm Phase 2 trial to evaluate the efficacy and safety of RP-A501, a recombinant adeno-associated virus serotype 9 (rAAV9) vector containing the human lysosome-associated membrane protein 2 isoform B (LAMP2B) transgene, in male patients with Danon disease.
Detailed description
RP-A501-0123 is a Phase 2 global, multi-center, single arm, open-label, single dose trial in males with Danon disease. The study is designed to assess the efficacy and safety of a single intravenous dose of RP-A501 in treating the cardiomyopathy associated with Danon disease.
RP-A501-0123 will enroll subjects ≥ 8 years of age with a pathogenic or likely pathogenic LAMP2 variant. The trial will include a total of 5 years of follow-up after administration of RP-A501.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Cohort 1: Adolescent/Adult males (age ≥ 15 years) [N=1 subject; enrollment closed] Cohort 2: Pediatric males (age 8 to 14 years) [N= 3 subjects; enrollment closed] Cohort 3: Males age ≥ 8 years receiving a pegcetacoplan-containing immunomodulatory regimen [N=2 subjects; enrollment closed] Cohort 4: Males age ≥ 8 years [N=12 subjects; enrolling]
| Arm | Type | Receives |
|---|---|---|
| RP-A501 | Experimental | Genetic: RP-A501A single intravenous infusion of RP-A501 in cohorts of subjects with a confirmed diagnosis of Danon disease. |
Who may qualify
- Ages
- 8 years and older
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (9 listed)
- Documentation of a pathogenic or likely pathogenic variant of the LAMP2 gene.
- Male.
- Age ≥8 years.
- Evidence of left ventricular hypertrophy with preserved systolic function phenotype as defined by each of the following:
- New York Heart Association (NYHA) Class II to III.
Key exclusion criteria (4 listed)
- Anti-AAV9 neutralizing antibody titer >1:40.
- Severe heart failure or requirement for advanced therapies (requirement for intravenous inotropic, vasodilator, or diuretic therapy within the 30 days prior to enrollment, presence or requirement for mechanical circulatory support (MCS), and presence or requirement for mechanical ventilation).
- History of intracardiac thrombosis or arterial thromboembolic events including stroke, transient ischemic attack (TIA), acute coronary syndrome, myocardial infarction or unstable angina.
- Prior cardiac or other organ (lung, liver, other) transplantation.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| RP-A501RP-A501 is a gene therapy product consisting of an rAAV9 capsid containing the human LAMP2B transgene which will be administered as a single IV infusion. Dose of RP-A501: Cohorts 1, 2 \& 3 = 6.7 x10^13 genome copies (GC)/kg; Cohort 4 = 3.8 x10^13 GC/kg. An immunomodulation regimen is initiated before RP-A501 administration to reduce the risk of gene therapy-related complications. The regimen includes rituximab or a biosimilar, administered in two doses for Cohorts 1-3 and three doses for Cohort 4, along with sirolimus and corticosteroids. Pegcetacoplan was incorporated into the immunomodulation regimen for Cohort 3 but excluded in Cohort 4. | Genetic | RP-A501 |
Primary outcome
Evaluation of Efficacy: Improvement as assessed via primary endpoint comprised of LAMP2 myocardial tissue expression and left ventricular mass index (LVMI)
Time frame: 12 months post-infusion
Myocardial tissue expression of LAMP2 protein improved from baseline to ≥ Grade 1 (by IHC), AND, ≥ 10% decrease in LVMI from baseline.
8 secondary outcomes
Evaluation of efficacy via components of the primary endpoint - LAMP2
Time frame: 12 months post infusion
Evaluation of efficacy via components of the primary endpoint - Left Ventricular Mass Index (LVMI)
Time frame: 12 months post infusion
Evaluation of efficacy via biomarker evidence of myocardial injury - High Sensitivity Troponin I (hsTnI)
Time frame: 12 months post infusion
Evaluation of efficacy via biomarker evidence of myocardial injury - N-Terminal Prohormone of Brain Natriuretic Peptide (NT-proBNP)
Time frame: 12 months post infusion
Evaluation of efficacy via Quality of Life
Time frame: 12 months post infusion
Evaluation of efficacy via heart failure symptoms
Time frame: 12 months post infusion
Evaluation of efficacy via assessment of event-free survival
Time frame: From infusion to 60 months post infusion
Evaluation of safety
Time frame: From infusion to 60 months post infusion
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Oct 2026.
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Rare Glycogen Storage Diseases Natural History Study
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Joseph Rossano, MD principal investigator
Children's Hospital of Philadelphia
Barry Greenberg, MD principal investigator
University of California, San Diego
6 sites in 4 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing RP-A501 in people with Danon Disease, run by Rocket Pharmaceuticals Inc. at 6 sites in 4 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 6 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in United States, Germany, Italy, United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Clinical Information (646-627-0033, clinicaltrials@rocketpharma.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Evaluation of Efficacy: Improvement as assessed via primary endpoint comprised of LAMP2 myocardial tissue expression and left ventricular mass index (LVMI) (time frame: 12 months post-infusion). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Oct 2026.