Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not recruitingRare disease

Study of SAT-3247 Compared to Placebo for Patients with Duchenne Muscular Dystrophy Who Can Walk

Verified siteInvestigational
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

A plain-language summary of the goals, design and what participants do

This study involves Duchenne muscular dystrophy, a condition where muscles gradually become weaker over time due to changes in a specific gene. The study will test a medicine called SAT-3247, which will be given as tablets taken by mouth. Some participants will receive SAT-3247 while others will receive placebo. The purpose of this study is to evaluate the safety of SAT-3247 in boys with Duchenne muscular dystrophy who are still able to walk, and to determine how SAT-3247 affects muscle strength as measured by special equipment at 12 weeks.

The study will involve boys between 7 and 10 years old who have Duchenne muscular dystrophy confirmed by genetic testing. Participants will need to be taking a stable dose of steroid medicine for at least 3 months before joining the study, or have stopped taking steroids at least 3 months before joining. Those taking other medicines for heart support or supplements that might affect muscles should be on stable doses for at least 1 month before starting. Participants should also be on a stable physical therapy routine for at least 2 months if they are doing such exercises. The study will last for 12 weeks during which participants will take the study medicine or placebo daily.

During the study, doctors will monitor safety by checking for any unwanted effects and by performing physical examinations, blood tests, heart monitoring with ECG, and other assessments. The main measurement of how well the treatment works will be changes in muscle strength tested with special equipment called dynamometry. Other measurements will include changes in muscle tissue examined through magnetic resonance imaging scans of the thigh muscle, a small sample of muscle tissue taken from the upper arm, and various tests of physical function including a test called NSAA that measures ability to perform different movements. Additional measurements will look at markers of muscle damage in the blood, lung function measured by spirometry, and detailed examination of muscle tissue samples to understand changes in muscle fibers and inflammation.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Baseline Assessment

    At the start of the trial, baseline measurements will be taken. These measurements will serve as a reference point to compare changes throughout the trial.

    Baseline assessments include muscle force measurements using a device called a dynamometer, which measures how strong your muscles are.

    Additional baseline tests include imaging of leg muscles using magnetic resonance imaging (a scan that creates detailed pictures of muscles), lung function tests using spirometry (a test that measures how well your lungs work), and functional assessments such as the NSAA (North Star Ambulatory Assessment, which evaluates your ability to perform daily movements).

    A small sample of muscle tissue from the upper arm will be taken through a procedure called a muscle biopsy. This allows doctors to examine the muscle cells under a microscope.

    Blood samples will be collected to measure certain substances in your blood, including creatine kinase (an enzyme that can indicate muscle damage) and inflammatory cytokines (proteins that show inflammation levels in the body).

  2. Step 2

    Treatment Assignment and Medication Start

    You will be randomly assigned to receive either SAT-3247 or placebo. A placebo looks like the actual medication but contains no active ingredient.

    Neither you nor the study doctors will know which treatment you are receiving. This is called a double-blind trial.

    The medication comes in tablet form and is taken by mouth.

    There are two possible doses of SAT-3247: 10 mg tablets or 50 mg tablets. The specific dose and number of tablets you will take depends on which treatment group you are assigned to.

    You will take the tablets daily for the duration of the treatment period.

  3. Step 3

    Treatment Period

    The treatment period lasts for 12 weeks.

    During this time, you will continue taking your assigned tablets every day.

    You must maintain stable doses of any other medications you are taking, including glucocorticoids (steroids such as prednisolone, deflazacort, or vamorolone), heart medications, and any supplements.

    If you are participating in physical therapy or strength training, you must continue the same routine throughout the trial without changes.

    Regular monitoring visits will occur during this period to check your safety and how you are responding to treatment.

  4. Step 4

    Safety Monitoring Throughout Treatment

    Throughout the 12-week treatment period, you will be monitored for any side effects or changes in your health.

    Safety assessments include physical examinations, blood tests to check how your organs are functioning, measurements of vital signs (such as blood pressure and heart rate), and electrocardiograms (tests that measure the electrical activity of your heart).

    A questionnaire called the C-SSRS (Columbia-Suicide Severity Rating Scale) will be used to assess your mental well-being.

    Any adverse events, meaning any unwanted or unexpected health problems, will be recorded and evaluated to determine if they are related to the study medication.

  5. Step 5

    Week 12 Assessment

    At the end of the 12-week treatment period, the same assessments performed at baseline will be repeated.

    Muscle force will be measured again using the dynamometer to see if there have been any changes compared to the beginning of the trial.

    Muscle imaging using magnetic resonance will be performed again to measure changes in intramuscular fat fraction (the amount of fat within the muscle) and T2 relaxation time (a measure that can indicate muscle damage or inflammation) in the thigh muscle.

    Another muscle biopsy will be taken from the upper arm to examine changes in muscle cells, including muscle fiber size, the presence of new muscle cells, and levels of scarring or fat tissue in the muscle.

    Functional assessments such as the NSAA and SV95C (a test measuring speed and velocity during climbing stairs) will be repeated.

    Lung function will be tested again using spirometry.

    Blood samples will be collected to measure changes in creatine kinase and inflammatory cytokines.

Who can join the trial?

14 criteria

  • The patient must be male and between 7 and 10 years old at the time of joining the study.
  • The patient must have a confirmed diagnosis of Duchenne muscular dystrophy, which is a muscle disease that causes muscle weakness. This diagnosis must be based on clinical findings and genetic testing showing a mutation in the DMD gene.
  • The patient must be able to walk on their own, meaning they are ambulatory.
  • The patient must be able to climb four stairs with an average time of 8 seconds or less, with times that do not vary by more than 1 second between two attempts.
  • The patient must be able to stand up from the floor in at least 3 seconds but less than 10 seconds, which is called time to rise.
  • The patient must be taking a stable dose of daily steroid medication such as prednisolone, deflazacort, or vamorolone for at least 3 months before joining and throughout the study. Patients who stopped taking steroids at least 3 months before joining are also allowed.
  • If the patient is taking other prescription medicines such as ACE inhibitors, which are medicines for the heart, beta-blockers, or diuretics, which help remove extra water from the body, the doses must be stable for at least 1 month before joining and throughout the study.
  • If the patient is taking herbal remedies or supplements that can affect muscle strength, such as Co-enzyme Q10 or creatine, within 4 weeks before joining, they must continue taking the same amount throughout the study.
  • If the patient is doing physical therapy or strength training, this must have been stable for at least 2 months before joining and must continue the same way throughout the study.
  • If the patient previously received gene therapy treatment called delandistrogene moxeparvovec or Elevidys more than 18 months before joining, they may be eligible if their muscle function has remained stable or declined for at least 3 months before joining, as confirmed by the doctor. Only a limited number of patients who received gene therapy can join.
  • If the patient previously received an exon skipper, which is a type of treatment for Duchenne muscular dystrophy, more than 6 months before joining, they may be eligible if their muscle function has remained stable or declined for at least 3 months before joining, as confirmed by the doctor.
  • The patient must be in good general health as determined by the doctor, including medical history, mental health history, physical examination, laboratory tests, and heart monitoring showing no significant problems.
  • The patient and caregiver must be able to communicate well with the study team and follow all study requirements, including visits, tests, questionnaires, and restrictions.
  • The patient's parent or legal guardian must provide written permission for the patient to join the study after reading the information and having the chance to discuss it with the study team. The patient will be asked to agree according to local rules.

Who cannot join the trial?

1 criterion

  • The information about reasons why patients cannot participate in this study has not been provided in the available data
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

  • SAT-3247

    is an investigational medication taken by mouth that is being studied for the treatment of Duchenne muscular dystrophy (DMD). This medication is being tested to see if it can help improve muscle strength in patients who are still able to walk. The study will look at how safe the medication is and whether it can increase muscle force after 12 weeks of treatment.

  • Placebo

    is an inactive substance that looks like the real medication but contains no active medicine. It is used in this study to compare the effects of SAT-3247 against no treatment, helping researchers determine if the actual medication is working.

What is already known about the treatment

SAT-3247 – SAT-3247 is an experimental medication taken by mouth that is currently being studied in clinical trials for the treatment of Duchenne muscular dystrophy, a genetic disorder that causes progressive muscle weakness and degeneration. The drug is being tested to see if it can improve muscle strength and function in patients who are still able to walk, with researchers measuring its effects using special equipment that tests how strong the muscles are. This medication is in the early stages of development (Phase 2a), meaning scientists are still working to find the right dose and determine whether it is safe and effective for treating this serious muscle disease.

Investigated diseases

Duchenne Muscular Dystrophy – Duchenne muscular dystrophy is a genetic disorder that causes progressive muscle weakness and degeneration. The condition primarily affects boys and begins in early childhood, usually between ages 3 and 5. Muscle weakness typically starts in the legs and pelvis before spreading to the arms, neck, and other areas of the body. As the disease progresses, individuals experience increasing difficulty with walking, climbing stairs, and maintaining balance. Most children with this condition require a wheelchair by their early teenage years. The progressive muscle deterioration also affects the heart and respiratory muscles over time.
Trial detailsLast updated 2 Oct 2026
Age0-17PhasePhase IITrial ID2025-522522-13-01Protocol codeSAT-3247-CL-201Estimated enrolment51 patientsSponsorSatellos Bioscience Inc.

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.