Patients with non-dystrophic myotonic syndromes (NDMs). NDMs are caused by mutations in the gene encoding for the skeletal muscle sodium (SCN4A) or chloride (CLCN1) channel. In this study patients with NDMs with a genetically confirmed mutation in the SCN4A-gene or the CLCN1-gene as registred in the Netherlands database of NDMs will be included.
Conditions
Interventions
Trade Name: Mexitil
Product Name: mexitil
Pharmaceutical Form: Tablet
INN or Proposed INN: MEXILETINE
CAS Number: 31828714
Current Sponsor code: -
Other descriptive name: Mexitil
Concentration unit
Sponsors
Radboud University Nijmegen Medical Center
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. At least 18 years of age 2. Genetically confirmed diagnosis of NDMs 3. Participation in the “Genetical variability of the Non-dystrophic Myotonia” study of J. Trip or a new patient with genetically confirmed NDM. Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range
Exclusion criteria
Exclusion criteria: 1. Inability or unwillingness to provide informed consent. 2. Other neurological conditions that might affect the assessment of the study measurements. 3. Genetic confirmed DM1 (CTG > 50 repeats), or DM2. 4. Patients with existing cardiac conduction defects, evidenced on ECG including but not limited to the following conditions: malignant arrhythmia or cardiac conduction disturbances (such as second degree AV block, third degree AV block, or prolonged QT interval >500 ms or QRS duration > 150 msec). 5. Current use of the following antiarrhythmic medication for a cardiac disorder: flecainide acetate, encainide, disopyramide, procainamide, quinidine, propafenone or mexiletine. 6. Women who are pregnant or lactating. 7. Patients currently on medications for myotonia such as phenytoin and flecainide acetate within 5 days of enrollment, carbamazepine and mexiletine within 3 days of enrollment, or propafenone, procainamide, disopyramide, quinidine and encainide within 2 days of enrollment. 8. Patients with an existing permanent pacemaker. 9. Patients with renal or hepatic disease, heart failure, or seizure disorders.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Primary end point(s): Because of the N-of-1 trials design primary end points will be evaluated by the trial statistician after each treatment pair. ;Main Objective: The objective of this project is to further refine N-of-1 trial methodology, and explore whether Bayesian analysis of multiple N-of-1 trials can serve as a sufficient basis for coverage decisions on drugs for rare diseases. ;Secondary Objective: The previously mentioned will be tested in combined N-of-1 trials using mexiletine vs. placebo in NDM patients. The secondary objective of this proposal is to assess whether mexiletine improves myotonia measured (both quantitatively and qualitative) in patients with non-dystrophic myotonia. | — |
Countries
Netherlands
Outcome results
None listed