Myotonic Dystrophy 1Phase 1/2NCT06138743
Study of SRP-1003 in Participants With Type 1 Myotonic Dystrophy
A Phase 1/2 study testing SRP-1003 IV Infusion and SRP-1003 SC Injection in people with Myotonic Dystrophy 1, run by Sarepta Therapeutics, Inc. at 35 sites in 11 countries.
Trial summary
This is a phase 1/2a double-blinded, placebo-controlled, dose-escalating study to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of single and multiple ascending doses of SRP-1003 compared to placebo in male and female participants with type 1 myotonic dystrophy (DM1). Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Myotonic Dystrophy 1
- What is being tested?
- SRP-1003 IV Infusion and SRP-1003 SC Injection
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 78 participants
- Where
- 35 sitesin 11 countries
- Study dates
- 4 Mar 2024to 31 Dec 2026
- Phase
- Phase 1/2
- 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 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Genetically confirmed diagnosis of DM1
- Clinician-assessed signs of DM1 including clinically apparent myotonia
- Onset of DM1 symptoms occurred after the age of 12 years
- Walk for at least 10 meters independently at screening
- Participants of childbearing potential must agree to use highly effective contraception in addition to a condom during the study and for at least 90 days following the end of study or last dose of study drug, whichever is later. Participants must not donate sperm or eggs during the study and for at least 90 days following the end of study or last dose of study drug whichever is later.
Who cannot join
- Inadequately controlled diabetes
- Confirmed diagnosis of congenital DM1
- Uncontrolled hypertension
- History of tibialis anterior (TA) biopsy within 3 months of Day 1 or planning to undergo TA biopsies during the study period
- Clinically significant cardiac, liver or renal disease
- Human immunodeficiency virus infection (seropositive) at screening
Show all 11Show fewer
- Seropositive for hepatitis B or hepatitis C at screening
- Untreated or poorly controlled epilepsy
- Treatment with anti-myotonia medication within a period of 5 half-lives of the medication prior to screening.
- Abnormal coagulation parameters at screening including platelet count, international normalized ratio, prothrombin time, and activated partial thromboplastin time
- Note: Additional inclusion/exclusion criteria may apply per protocol
Trial locations and contacts
35 sites in 11 countries. Contact the study team or a site near you to ask about taking part.
35 sites in 11 countries
Australia6 sites
Sunshine Coast University Hospital
Birtinya, Queensland, 4575
Royal Brisbane And Women's Hospital
Herston, Queensland
Nucleus Network Brisbane Clinic
Herston
Liverpool Hospital
Liverpool, New South Wales, 2170
Alfred Health
Melbourne, Victoria, 3004
Mater Hospital Brisbane
South Brisbane
France5 sites
University Hospital of Angers
Angers
Centre Hospitalier Universitaire De Bordeaux
Bordeaux
Centre Hospitalier Universitaire De Lille
Lille
CHU de Nice - Hôpital Pasteur 2
Nice
Assistance Publique Hôpitaux De Paris
Paris
Italy4 sites
Fondazione Serena Onlus - Centro Clinico Nemo Brescia
Gussago
Centro Clinico Nemo (Milan)
Milan
Azienda Ospedaliera Universitaria Pisana (AOUP)
Pisa
Fondazione Policlinico Universitario Agostino Gemelli IRCCS
Roma
Canada3 sites
University Of Calgary
Calgary
University Of Alberta
Edmonton
McGill University
Montreal
Spain3 sites
Hospital Universitario Torrecárdenas
Almería
Hospital Universitari Vall D Hebron
Barcelona
Hospital Universitario Infanta Sofia
Madrid
Taiwan3 sites
China Medical University Hospital
Taichung, 40447
National Taiwan University Hospital
Taipei
Taipei Veterans General Hospital
Taipei
Thailand3 sites
Siriraj Hospital
Bangkok, 10700
Songklanagarind Hospital
Hat Yai, Changwat Songkhla, 90110
Lampang Hospital
Lampang, 52000
United Kingdom3 sites
The National Hospital for Neurology and Neurosurgery, NHS Foundation Trust
London
Nottingham University Hospitals NHS Trust
Nottingham
Southampton General Hospital, NHS Foundation Trust
Southampton
Germany2 sites
Klinikum der Universität München AöR
Munich
Deutsches Zentrum für Neurodegenerative Erkrankungen e.V.
Ulm
New Zealand1 site
New Zealand Clinical Research Christchurch
Christchurch, 8011
About this study
Official title: A Phase 1/2a Dose-Escalating Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of ARO-DM1 (SRP-1003) in Subjects With Type 1 Myotonic Dystrophy Who Are ≥18 to ≤ 65 Years
This is a phase 1/2a double-blinded, placebo-controlled, dose-escalating study to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of single and multiple ascending doses of SRP-1003 compared to placebo in male and female participants with type 1 myotonic dystrophy (DM1). Participants who have provided written informed consent and met all protocol eligibility requirements will be randomized to receive single (Part 1) or multiple (Part 2) doses of SRP-1003 or placebo.
- Conditions
- Myotonic Dystrophy 1
- Being tested
- SRP-1003 IV Infusion, Placebo IV Infusion, SRP-1003 SC Injection, Placebo SC Injection
- Keywords
- Myotonic Dystrophy 1, SRP-1003, ARO-DM1
- Medical subject headings
- Myotonic Dystrophy
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SRP-1003 IV InfusionDrug
Also called ARO-DM1 IV Infusion
SRP-1003 by IV infusion
Placebo IV InfusionDrug
0.9% sodium chloride (NaCl) calculated volume to match active treatment by IV infusion
SRP-1003 SC InjectionDrug
Also called ARO-DM1 SC Injection
SRP-1003 by SC injection(s)
Placebo SC InjectionDrug
0.9% NaCl calculated volume to match active treatment by SC injection(s)
| Study group | Role | What they receive |
|---|---|---|
| SRP-1003 IV Infusion | Experimental | Single or multiple doses of SRP-1003 by intravenous (IV) infusion Receives: Drug: SRP-1003 IV Infusion |
| Placebo by IV Infusion | Placebo comparator | Single or multiple doses of placebo by IV infusion Receives: Drug: Placebo IV Infusion |
| SRP-1003 SC Injection | Experimental | Single or multiple doses of SRP-1003 by subcutaneous (SC) injection Receives: Drug: SRP-1003 SC Injection |
| Placebo by SC Injection | Placebo comparator | Single or multiple doses of placebo by SC injection Receives: Drug: Placebo SC Injection |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants with Treatment-emergent Adverse Events Over Time Through End of Study (EOS)
Measured: Single-dose phase (Part 1): Up to Day 90 (EOS); multiple-dose phase (Part 2): Up to Day 180 (EOS)
Secondary outcomes (11)
PK of SRP-1003: Maximum Observed Plasma Concentration (Cmax)
Measured: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
PK of SRP-1003: Area Under the Plasma Concentration Versus Time Curve from Zero to 24 Hours (AUC0-24)
Measured: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
PK of SRP-1003: Area Under the Plasma Concentration Versus Time Curve from Zero to the Last Quantifiable Plasma Concentration (AUClast)
Measured: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
PK of SRP-1003: Area Under the Plasma Concentration Versus Time Curve from Zero to Infinity (AUCinf)
Measured: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
Change from Baseline at Day 120 for Video Hand Opening Time (vHOT)
Measured: (Part 2): Baseline, Day 120
Change from Baseline Over Time for the Timed Up and Go Test (TUG) Assessment
Measured: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the 10-Meter Walk/Run Test (10MWT) Assessment
Measured: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Hand-held Quantitative Dynamometry Assessment
Measured: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Video Hand Opening Time (vHOT) Assessment
Measured: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Myotonic Dystrophy Type 1 Activity and Participation Scale (DM1-Activ-C) Assessment
Measured: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Myotonic Dystrophy Health Index (MDHI) Assessment
Measured: (Part 2): Baseline through EOS (up to 180 days)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Nov 2023
- Study start4 Mar 2024
- Primary completion31 Dec 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Myotonic Dystrophy 1Studies of the same condition, open and under way.
- More trials run by Sarepta Therapeutics, 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 1/2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 78 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Sarepta Therapeutics, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Medical Director, Study director, Sarepta Therapeutics, Inc.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06138743
- Sponsor's protocol ID
- SRP-1003-101
- Other IDs
- 2024-513579-42-00
- Status last verified
- Oct 2026
- First submitted
- 14 Nov 2023
- Last updated
- 5 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 5 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1/2a Dose-Escalating Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of ARO-DM1 (SRP-1003) in Subjects With Type 1 Myotonic Dystrophy Who Are ≥18 to ≤ 65 Years
- ClinicalTrials.gov ID
- NCT06138743
- Acronym / sponsor ID
- SRP-1003-101
- Conditions
- Myotonic Dystrophy 1
- Keywords
- Myotonic Dystrophy 1, SRP-1003, ARO-DM1
- Phase
- Phase 1/2
- Study type
- Interventional
- Recruitment status
- Enrolling by invitation
- Enrolment
- 78 participants (estimated)
- Lead sponsor
- Sarepta Therapeutics, Inc.Industry (pharma, biotech, devices)
- Study start
- 4 Mar 2024 (actual)
- Primary completion
- 31 Dec 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 18 Nov 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 phase 1/2a double-blinded, placebo-controlled, dose-escalating study to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of single and multiple ascending doses of SRP-1003 compared to placebo in male and female participants with type 1 myotonic dystrophy (DM1). Participants who have provided written informed consent and met all protocol eligibility requirements will be randomized to receive single (Part 1) or multiple (Part 2) doses of SRP-1003 or placebo.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| SRP-1003 IV Infusion | Experimental | Drug: SRP-1003 IV InfusionSingle or multiple doses of SRP-1003 by intravenous (IV) infusion |
| Placebo by IV Infusion | Placebo comparator | Drug: Placebo IV InfusionSingle or multiple doses of placebo by IV infusion |
| SRP-1003 SC Injection | Experimental | Drug: SRP-1003 SC InjectionSingle or multiple doses of SRP-1003 by subcutaneous (SC) injection |
| Placebo by SC Injection | Placebo comparator | Drug: Placebo SC InjectionSingle or multiple doses of placebo by SC injection |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Genetically confirmed diagnosis of DM1
- Clinician-assessed signs of DM1 including clinically apparent myotonia
- Onset of DM1 symptoms occurred after the age of 12 years
- Walk for at least 10 meters independently at screening
- Participants of childbearing potential must agree to use highly effective contraception in addition to a condom during the study and for at least 90 days following the end of study or last dose of study drug, whichever is later. Participants must not donate sperm or eggs during the study and for at least 90 days following the end of study or last dose of study drug whichever is later.
Key exclusion criteria (11 listed)
- Inadequately controlled diabetes
- Confirmed diagnosis of congenital DM1
- Uncontrolled hypertension
- History of tibialis anterior (TA) biopsy within 3 months of Day 1 or planning to undergo TA biopsies during the study period
- Clinically significant cardiac, liver or renal disease
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 |
|---|---|---|
| SRP-1003 IV InfusionAlso: ARO-DM1 IV InfusionSRP-1003 by IV infusion | Drug | SRP-1003 IV Infusion |
| Placebo IV Infusion0.9% sodium chloride (NaCl) calculated volume to match active treatment by IV infusion | Drug | Placebo by IV Infusion |
| SRP-1003 SC InjectionAlso: ARO-DM1 SC InjectionSRP-1003 by SC injection(s) | Drug | SRP-1003 SC Injection |
| Placebo SC Injection0.9% NaCl calculated volume to match active treatment by SC injection(s) | Drug | Placebo by SC Injection |
Primary outcome
Number of Participants with Treatment-emergent Adverse Events Over Time Through End of Study (EOS)
Time frame: Single-dose phase (Part 1): Up to Day 90 (EOS); multiple-dose phase (Part 2): Up to Day 180 (EOS)
11 secondary outcomes
PK of SRP-1003: Maximum Observed Plasma Concentration (Cmax)
Time frame: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
PK of SRP-1003: Area Under the Plasma Concentration Versus Time Curve from Zero to 24 Hours (AUC0-24)
Time frame: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
PK of SRP-1003: Area Under the Plasma Concentration Versus Time Curve from Zero to the Last Quantifiable Plasma Concentration (AUClast)
Time frame: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
PK of SRP-1003: Area Under the Plasma Concentration Versus Time Curve from Zero to Infinity (AUCinf)
Time frame: Single-dose phase (Part 1): Up 24 hours post-dose; multiple-dose phase (Part 2): Through 24 hours post first and second dose
Change from Baseline at Day 120 for Video Hand Opening Time (vHOT)
Time frame: (Part 2): Baseline, Day 120
Change from Baseline Over Time for the Timed Up and Go Test (TUG) Assessment
Time frame: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the 10-Meter Walk/Run Test (10MWT) Assessment
Time frame: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Hand-held Quantitative Dynamometry Assessment
Time frame: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Video Hand Opening Time (vHOT) Assessment
Time frame: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Myotonic Dystrophy Type 1 Activity and Participation Scale (DM1-Activ-C) Assessment
Time frame: (Part 2): Baseline through EOS (up to 180 days)
Change from Baseline Over Time for the Myotonic Dystrophy Health Index (MDHI) Assessment
Time frame: (Part 2): Baseline through EOS (up to 180 days)
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 5 Oct 2026.
- Individual participant dataSharing planned: No
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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.
Medical Director study director
Sarepta Therapeutics, Inc.
35 sites in 11 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1/2 study testing SRP-1003 IV Infusion and SRP-1003 SC Injection in people with Myotonic Dystrophy 1, run by Sarepta Therapeutics, Inc. at 35 sites in 11 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 5 inclusion and 11 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: enrolling by invitation, as of the sponsor's last update on 5 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 35 sites in Australia, France, Italy, Canada, Spain and 6 more countries. 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
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?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of Participants with Treatment-emergent Adverse Events Over Time Through End of Study (EOS) (time frame: Single-dose phase (Part 1): Up to Day 90 (EOS); multiple-dose phase (Part 2): Up to Day 180 (EOS)). 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 5 Oct 2026.