A Phase 1/2 interventional study of SRP-1001 for Injection and Placebo in Muscular Dystrophy, Facioscapulohumeral, sponsored by Sarepta Therapeutics, Inc.. Enrolling by invitation at 16 sites in 7 countries. Open to participants aged 16 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-10-05.
Sponsored by Sarepta Therapeutics, Inc. · Phase 1/2, Interventional, and Treatment
The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of SRP-1001 in participants with facioscapulohumeral muscular dystrophy Type 1 (FSHD1). In Part 1 of the study, participants will receive one dose of SRP-1001 or placebo. In Part 2 of the study, participants will receive 4 doses of SRP-1001 or placebo. Participants who complete Part 1 will have the option to re-screen and re-randomize into Part 2. All participants will undergo pre- and post-dose magnetic imaging resonance (MRI)-guided muscle biopsies (a total of 2 biopsies). Participants who complete Part 1 and enroll in Part 2 will be required to undergo an additional screening biopsy. Participants completing Part 1 or Part 2 may have the option to continue to receive drug in an open-label extension study or may be eligible to participate in later-stage clinical studies.
79 studies on the registry are indexed under Muscular Dystrophy, Facioscapulohumeral; 26 are open to participants now.
This study's planned enrollment of 60 is above the median of 48 across 49 interventional studies indexed under Muscular Dystrophy, Facioscapulohumeral.
Browse Muscular Dystrophy, Facioscapulohumeral studies →Sarepta Therapeutics, Inc. is the lead sponsor of 52 studies on the registry; 8 are open to participants now.
Of its 21 completed or terminated interventional studies of FDA-regulated products, 12 (57%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Note: additional inclusion/exclusion criteria may apply per protocol
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
SRP-1001 for injection
Drug: SRP-1001 for Injection
Sodium chloride (0.9%)
Drug: Placebo
Single or multiple doses of SRP-1001 by intravenous (IV) infusion
Also known as: ARO-DUX4 for Injection
Calculated volume to match active treatment by IV infusion
Number of Participants With Treatment-Emergent Adverse Events Over Time Through End of Study
Time frame: Part 1: Up to Day 90; Part 2: Up to Day 360
PK of SRP-1001: Maximum Observed Plasma Concentration (Cmax)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Area Under the Plasma Concentration Versus Time Curve from Zero to 24 Hours (AUC0-24)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Area Under the Plasma Concentration Versus Time Curve from Zero to the Last Quantifiable Plasma Concentration (AUClast)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Area Under the Plasma Concentration Versus Time from Zero to Infinity (AUCinf)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Terminal Elimination Half-Life (t1/2)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Systemic Clearance (CL)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Volume of Distribution (Vss)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Recovery of Unchanged Drug in Urine Over 0-24 Hours (Amount Excreted: Ae)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Fraction of Drug Excreted in Urine as Percent of IV Dose (Fe)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
PK of SRP-1001: Renal Clearance (CLr)
Time frame: Part 1: through 48 hours post-dose (all cohorts) and through 48 hours post second dose (Cohorts 3 & 4 only); Part 2: through 8 hours post first and second dose
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Muscular Dystrophy, Facioscapulohumeral →