Hope for myotonic dystrophy: new drug shows promise in easing muscle stiffness Long-Term

NCT ID NCT06549400

ENROLLING_BY_INVITATION Symptom relief Sponsor: Lupin Ltd. Source: ClinicalTrials.gov ↗

First seen Jun 25, 2026 · Last updated Jun 27, 2026 · Updated 1 time

Summary

This study is testing the long-term safety and effectiveness of a drug called mexiletine PR for people with myotonic dystrophy types 1 and 2. The drug is taken once daily as a liquid to help reduce muscle stiffness (myotonia). The study includes 176 adults and teens who have already completed a previous trial. Researchers will measure how quickly hand muscles relax after a strong squeeze and track any side effects over 26 weeks.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance
mexiletine PR (prolonged-release granules for oral suspension)
What this could lead to
If successful, this could confirm a safe, long-term treatment option to reduce muscle stiffness and improve daily function for people with myotonic dystrophy.
What could go wrong
This is an extension study, so participants already tolerated the drug; however, long-term side effects are still being monitored, and the results may not apply to all patients.

This is an AI summary of the original study and may miss details. Read our disclaimer.

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Conditions

The condition(s) this trial relates to.

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Locations

  • Aarhus University Hospital

    Aarhus, Denmark

  • Azienda Ospedaliera Universitaria Policlinico Tor Vergata

    Rome, Italy

  • Laboratory for Muscle Diseases and Neuropathies

    Leuven, Belgium

  • Ludug-Maximilians University

    München, Germany

  • University College Hospital

    London, United Kingdom

  • University Hospital of Madrid

    Madrid, Spain

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