An Open-Label, Randomized, Cross-Over Study to Investigate the Efficacy and Safety of Mexiletine PR compared to Mexiletine IR in Patients with Non-Dystrophic Myotonias (ACHILLES study)

Status

Recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTIS

Registry ID

CTIS2024-514970-27-00

Acronym

MEX-NDM-301

Enrollment

Registered

2025-02-14

Start date

2025-09-03

Completion date

Unknown

Last updated

2025-09-30

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

Conditions

Non-Dystrophic Myotonias (NDM)

Brief summary

Incidence of treatment emergent Adverse Events (TEAEs), treatment-related TEAEs, serious AEs, AEs of Special Interest (AESIs), and patient discontinuation rate between mexiletine PR and mexiletine IR after 12 weeks of treatment.

Detailed description

Video-recording of hand opening time (VHOT), Individualized Neuromuscular Quality of Life Questionnaire (INQoL), Myotonia Behavior Scale (MBS), Timed “Up & Go” (TUG) Test, Visual Analog Scale (VAS) for myotonia/stiffness, Clinical Global Impression (CGI) – Efficacy, Clinical Global Impression (CGI) – Tolerability Index

Interventions

DRUGMexiletine granules for prolonged-release oral suspension 500 mg

DRUGNamuscla 167 mg hard capsules

DRUGMexiletine granules for prolonged-release oral suspension 333 mg

DRUGMexiletine granules for prolonged-release oral suspension 167 mg

Eligibility

Sex/Gender

All

Age

0 Years to No maximum

Design outcomes

Primary

Measure	Time frame
Incidence of treatment emergent Adverse Events (TEAEs), treatment-related TEAEs, serious AEs, AEs of Special Interest (AESIs), and patient discontinuation rate between mexiletine PR and mexiletine IR after 12 weeks of treatment.	—

Secondary

Measure	Time frame
Video-recording of hand opening time (VHOT), Individualized Neuromuscular Quality of Life Questionnaire (INQoL), Myotonia Behavior Scale (MBS), Timed “Up & Go” (TUG) Test, Visual Analog Scale (VAS) for myotonia/stiffness, Clinical Global Impression (CGI) – Efficacy, Clinical Global Impression (CGI) – Tolerability Index	—

Countries

Belgium, France, Germany, Italy

Outcome results

None listed

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