A Randomized, Double-Blind, Placebo-Controlled, Multi-Center Study to Investigate the Efficacy and Safety of Once Daily Mexiletine PR During 26 Weeks of Treatment in Patients with Myotonic Dystrophy Type 1 and Type 2

Status

Recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTIS

Registry ID

CTIS2024-511179-13-00

Acronym

MEX-DM-302

Enrollment

146

Registered

2024-09-04

Start date

2025-01-13

Completion date

Unknown

Last updated

2025-11-19

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Myotonic Dystrophy type 1 and type 2 (DM1/DM2)

Brief summary

Handgrip relaxation time in DM1 patients: Mean change from baseline in relaxation time of handgrip after maximal voluntary isometric contraction (MVIC) of the dominant hand using a handgrip dynamometer at Week 26.

Detailed description

Handgrip Dynamometer (Week 14), Individualized Neuromuscular Quality of Life Questionnaire (INQoL) locking domain, Myotonia Behavior Scale (MBS), Visual Analog Scale (VAS) for myotonia, 10 meter Walk Test (10mWT), DM1-Active-c

Interventions

DRUGMexiletine granules for prolonged-release oral suspension 167 mg

DRUGMexiletine granules for prolonged-release oral suspension 333 mg

DRUGPlacebo to Mexiletine granules for prolonged-release oral suspension 167 mg

DRUG333 mg

DRUGand 500 mg

DRUGMexiletine granules for prolonged-release oral suspension 500 mg

Eligibility

Sex/Gender

All

Age

0 Years to No maximum

Design outcomes

Primary

Measure	Time frame
Handgrip relaxation time in DM1 patients: Mean change from baseline in relaxation time of handgrip after maximal voluntary isometric contraction (MVIC) of the dominant hand using a handgrip dynamometer at Week 26.	—

Secondary

Measure	Time frame
Handgrip Dynamometer (Week 14), Individualized Neuromuscular Quality of Life Questionnaire (INQoL) locking domain, Myotonia Behavior Scale (MBS), Visual Analog Scale (VAS) for myotonia, 10 meter Walk Test (10mWT), DM1-Active-c	—

Countries

Belgium, Denmark, Germany, Italy, Spain

Outcome results

None listed

Source: EU CTIS · Data processed: Feb 4, 2026