Phase II Therapeutic Trial of Mexiletine in Non-Dystrophic Myotonia (IND #77,021) - ND

Active, not recruiting

Conditions: Myotonic disorders are divided into dystrophic myotonias (DM1 and DM2) and non-dystrophic myotonias (NDM). The dystrophic myotonias are associated with significant progressive muscular weakness and other systemic organ involvement. On the other hand, NDM usually presents with muscle stiffness as the primary symptom, and severe weakness is not considered a major feature, especially in myotonia congenita.
MedDRA version: 14.0Level: LLTClassification code 10032487Term: Other specific muscle disordersSystem Organ Class: 10028395 - Musculoskeletal and connective tissue disorders
Therapeutic area: Diseases [C] - Nervous System Diseases [C10]

Registration Number: EUCTR2009-011184-36-IT

Lead Sponsor: Dept. of Neurology - Univ. of Kansas Medical Center

Brief Summary: Not available

Detailed Description: Not available

Recruitment & Eligibility

Status: Not Recruiting

Sex: All

Target Recruitment: 60

Inclusion Criteria

At least 16 years of age 2. Clinical symptoms or signs suggestive of myotonic disorders 3. Presence of myotonic potentials on electromyography (EMG) 4. Participation in the Non-Dystrophic Myotonia Natural History study or a new patient with genetic confirmed NDM
Are the trial subjects under 18? yes
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

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 EKG 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. 10. Patients on medications that produce myotonia. This includes one or more of the following: a. fibrate acid derivatives, b. hydroxymethylglutaryl CoA reductase inhibitors c. chloroquine d. colchicines

Study & Design

Study Type: Interventional clinical trial of medicinal product

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Main Objective: The specific aim of this proposal is to perform a randomized, double-blind, placebo-controlled crossover study to assess whether mexiletine improves both quantitative and qualitative measures of myotonia in patients with non-dystrophic myotonia.;Secondary Objective: -;Primary end point(s): Participant-assessed stiffness as measured by IVR. Data from the NDM natural history study has shown that stiffness is the most common symptom NDM patients encountered; and there is minimal variation of the reported symptom frequency from week to week (Wang, 2007). Therefore, the primary outcome measure will be the mean daily IVR participantassessed severity of stiffness in weeks 2 & 3, and 7 & 8.

Secondary Outcome Measures