Zeleciment Basivarsen (DYNE-101) for people with myotonic dystrophy type 1

A Phase 3, Randomized, Double-Blind, 48-Week Placebo-Controlled Study to Assess the Efficacy, Safety, and Tolerability of DYNE-101 Administered to Participants With Myotonic Dystrophy Type 1

Phase 3 Interventional Dyne Therapeutics · NCT07486934

This trial will test whether Zeleciment Basivarsen (DYNE-101) improves symptoms and is safe and tolerable for adults with myotonic dystrophy type 1.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment150 (estimated)
Ages16 Years and up
SexAll
SponsorDyne Therapeutics Industry-sponsored
Locations5 sites (Atlanta, Georgia and 4 other locations)
Trial IDNCT07486934 on ClinicalTrials.gov

What this trial studies

This Phase 3, interventional study enrolls adults with genetically confirmed myotonic dystrophy type 1 (DM1) to receive Zeleciment Basivarsen (DYNE-101) or placebo during a 48-week placebo-controlled period followed by a 24-week long-term extension. Eligible participants must have a CTG repeat size >100, be able to walk 10 meters and complete five sit-to-stand maneuvers independently, and have a BMI below 35 kg/m2. The protocol includes up to 8 weeks of screening and regular safety and tolerability reviews by an independent data monitoring committee. Study visits are conducted at participating U.S. clinical sites with serial clinical assessments and safety monitoring throughout the treatment periods.

Who should consider this trial

Good fit: Ideal candidates are ambulatory adults with genetically confirmed DM1 (CTG repeat >100), a BMI under 35 kg/m2, and the ability to complete the required physical tests.

Not a fit: Patients with congenital DM1, those who are non-ambulatory or who do not meet the genetic or physical test criteria, or those excluded for recent major surgery or certain medications may not benefit from participation.

Why it matters

Potential benefit: If successful, the treatment could slow disease progression and improve muscle function and myotonia symptoms in people with DM1.

How similar studies have performed: Preclinical work and early-phase trials of DMPK-targeting oligonucleotides have shown promise, but large randomized Phase 3 evidence for this approach is still limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Diagnosis of DM1 confirmed by molecular genetics with trinucleotide repeat size greater than (\>) 100. Historical results from clinical testing are acceptable.
* Able to walk 10 meters and complete 5 times sit to stand independently (inserts or supports that don't go above the ankle are allowed).
* Body mass index (BMI) less than (\<) 35 kilograms per meter square (kg/m\^2).

Exclusion Criteria:

* A known diagnosis of congenital DM1.
* History of major surgical procedure (based on Investigator judgment) within 12 weeks prior to the start of screening, with the exception of implanted pacemaker or defibrillator.
* Use of glucagon-like peptide 1 (GLP-1) agonist/incretin medications including semaglutide, dulaglutide, liraglutide, exenatide, or tirzepatide within a period of 5 half-lives of the medication prior to performing screening assessments.

Note: Other inclusion and exclusion criteria may apply.

Where this trial is running

Atlanta, Georgia and 4 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Myotonic Dystrophy Type 1DM1Myotonic DystrophySteinert DiseaseSteinertMyotonic Dystrophy 1MyotoniaDystrophy Myotonic
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.