Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

RecruitingRare disease

Long‑Term Safety and Efficacy Study of ENTR‑601‑45 and ENTR‑601‑44 in Participants with Duchenne Muscular Dystrophy

Verified siteInvestigationalNo placebo
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

The study focuses on Duchenne Muscular Dystrophy, a rare genetic condition that causes progressive muscle weakness. Participants receive an investigational medicine called ENTR-601-45 or ENTR-601-44, which are given by intravenous infusion. These drugs belong to a special class designed to help the body skip over faulty sections of the gene (a process known as exon skipping) and use a delivery system referred to as an endosomal escape vehicle phosphorodiamidate morpholino oligomer platform to reach muscle cells.

The main goal of the trial is to evaluate the long‑term safety and tolerability of the study drug in people with the condition. After an initial screening, participants receive the medication at regular intervals for an extended period, during which doctors monitor vital signs, blood tests, heart recordings, and physical examinations. Simple walking and climbing tests are performed at the start and at later visits to see how the treatment may affect mobility.

Throughout the study, blood samples are taken to measure how much of the medicine remains in the body and to check for any immune response. All observations are recorded to help determine whether the therapy is safe for continued use over time.

The research process

The trial runs in 7 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial enrollment and baseline assessments

    upon joining the study, baseline measurements are taken to record current health status. these include vital signs such as blood pressure and heart rate, basic laboratory tests, an electrocardiogram (ecg) to check heart rhythm, and a physical examination.

    the purpose of these assessments is to provide reference points for later comparison during the study.

  2. Step 2

    First intravenous infusion of entr-601-45

    the participant receives a solution for infusion called entr-601-45. the dose is 20 mg/kg, meaning 20 milligrams of medication for each kilogram of body weight.

    the medication is administered through an intravenous infusion, which involves delivering the drug directly into a vein over a short period of time.

  3. Step 3

    First intravenous infusion of entr-601-44

    the participant receives a second solution for infusion called entr-601-44. the dose is 18 mg/kg, meaning 18 milligrams of medication for each kilogram of body weight.

    this medication is also given by intravenous infusion, using a vein as the route of delivery.

  4. Step 4

    Regular safety monitoring visits

    at each scheduled visit, the study team checks for any new or worsening health problems, known as treatment‑emergent adverse events (teaes).

    measurements include vital signs, repeat laboratory tests, another ecg, and a physical examination to track safety over time.

  5. Step 5

    Efficacy assessments

    the participant performs simple functional tests to evaluate muscle strength and mobility. these tests include a 10‑meter walk/run, timed rise from floor, timed 4‑stair climb, stride velocity at the 95th percentile, the north star ambulatory assessment, and the performance of the upper limb version 2.0.

    each test is done in a standard way so that changes can be compared to the baseline measurements.

  6. Step 6

    Blood sampling for drug levels and antibody testing

    blood samples are taken to measure the concentration of the study drugs in the plasma and to detect any anti‑drug or anti‑dystrophin antibodies, which are proteins that the body might produce against the medication.

  7. Step 7

    Continuation of treatment until study end

    the participant continues to receive the specified doses of entr-601-45 and entr-601-44 by intravenous infusion according to the study schedule for the duration of the long‑term extension period.

    ongoing safety checks and efficacy assessments are performed throughout this time to gather long‑term data.

Who can join the trial?

5 criteria

  • Must be a male (boy) who has Duchenne muscular dystrophy.
  • Must be between the ages of 2 and 3 years.
  • Must be able to give consent (agree to join the study if he is an adult) or assent (agree to join the study if he is a child).
  • Must have already finished the earlier clinical trial called ENTR‑601‑44‑201 or ENTR‑601‑45‑201.
  • If he is sexually active with a female partner who could become pregnant, he must agree to use condoms during sexual intercourse.

Who cannot join the trial?

1 criterion

  • If there has been any change to the rules used in the earlier related study (parent study), such as a health problem that occurred during that study (safety events), and the doctor in charge of the trial (investigator) together with the safety‑watching doctor (medical monitor) or the company’s representative (sponsor designee) decides that it would not be safe (precludes safe use) for you to take the study drug, you cannot join the trial.
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.

RecruitingNot yet 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

  • ENTR-601-45

    is an experimental medicine that is given through an intravenous (IV) infusion. It belongs to a group of drugs called phosphorodiamidate morpholino oligomers, which are designed to “skip” a specific part of the genetic code (an exon) that is faulty in Duchenne muscular dystrophy. By skipping this exon, the drug aims to help the body produce a healthier version of the protein dystrophin, which is missing or broken in people with this disease. In the study, the medicine is being evaluated for how safe it is to use over a long period, how well patients tolerate it, how it moves through the body, and whether it improves muscle function.

  • ENTR-601-44

    is another experimental medicine tested in the same way, also given by IV infusion. Like ENTR-601-45, it is a phosphorodiamidate morpholino oligomer that works by skipping a different exon that can also help restore the production of functional dystrophin in Duchenne muscular dystrophy. The trial is looking at its long‑term safety, how patients feel while taking it, how the drug is processed in the body, and whether it can help maintain or improve muscle strength and overall health.

What is already known about the treatment

  • ENTR-601-45

    This medication is given as an intravenous infusion of a clear solution that is slowly dripped into a vein. It is still an investigational drug being studied in Phase 2 clinical trials, so it is not yet approved for general medical use. The drug is being tested to treat Duchenne muscular dystrophy in patients whose genes can be corrected by skipping a faulty segment. It works by using a special carrier that helps a short piece of genetic material enter cells and direct them to skip the bad exon, allowing the muscle cells to make a shorter but functional protein; it is classified as an antisense oligonucleotide (exon‑skipping) therapy delivered with an endosomal escape vehicle.

  • ENTR-601-44

    This medication is also administered as an intravenous infusion of a sterile solution that is delivered through a vein. Like ENTR‑601‑45, it is still in the experimental stage and is being evaluated in a Phase 2 study, so it has not received regulatory approval. It is intended for the same purpose: to help patients with Duchenne muscular dystrophy who can benefit from exon skipping. The drug uses a carrier to bring a short DNA‑like strand into muscle cells, where it tells the cell to skip the problematic exon and produce a functional version of the missing protein; it belongs to the antisense oligonucleotide (exon‑skipping) class combined with an endosomal escape vehicle.

Investigated diseases

Duchenne muscular dystrophy - Duchenne muscular dystrophy is a genetic disorder that causes progressive weakening of the muscles. It appears in early childhood, often before age five, and the muscle weakness starts in the legs and pelvis. As the disease advances, the arms, neck, and respiratory muscles become affected. Children may have difficulty walking, climbing stairs, and raising from the floor. Over time, the ability to move independently decreases, and the condition can affect posture and coordination.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2025-525124-10-00Protocol codeENTR-601-DMD-202Estimated enrolment80 patientsSponsorEntrada Therapeutics 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.