An Observational Study to Describe the Long-term Safety and Effectiveness of Namuscla in the Symptomatic Management of Myotonia in Adult Patients with Non-dystrophic Myotonic Disorders

Study type

• Study type:
  Non-interventional study
• Scope of the study:
  Assessment of risk minimisation measure implementation or effectiveness

  Effectiveness study (incl. comparative)

  Safety study (incl. comparative)

Non-interventional study

• Non-interventional study design:
  Other
• Non-interventional study design, other:
  Non-interventional Prospective Post Authorisation Safety Study (PASS)

Study drug and medical condition

• Study drug International non-proprietary name (INN) or common name:
  MEXILETINE HYDROCHLORIDE
• Anatomical Therapeutic Chemical (ATC) code:
  (C01BB02) mexiletine

  mexiletine
• Medical condition to be studied:
  Myotonia

Population studied

• Age groups:
  • Adult and elderly population (≥18 years)

    • Adults (18 to < 65 years)

      • Adults (18 to < 46 years)
      • Adults (46 to < 65 years)
    • Elderly (≥ 65 years)

      • Adults (65 to < 75 years)
      • Adults (75 to < 85 years)
      • Adults (85 years and over)
• Special population of interest:
  Hepatic impaired

  Immunocompromised

  Renal impaired
• Estimated number of subjects:
  50

Study design details

• Main study objective:
  Primary Objective: To describe the long-term safety and tolerability of Namuscla for the symptomatic treatment of myotonia in adult patients with non-dystrophic myotonic disorders.
• Outcomes:
  Outcome Variables: Primary: 1. Proportion of patients with treatment-emergent AEs (TEAEs, including SAEs) from study enrolment to 6, 12, 24 and 36 months on Namuscla, 2. Proportion of patients requiring dose reduction or treatment discontinuation due to AEs (including SAEs). Safety:1Proportion of pts with AEs/SAEs/AESI from study enrolment to 6,12,24,and 36 months.2. Proportion of AEs in pts with abnormal hepatic function 3.Number of AEs in pts with abnormal renal function 4.Number of AEs in geriatric pts 5.Number of pts with cardiac arrhythmia,SCAR,DRESS,SJS,seizures.Efficacy:6.Change VAS,stiffness,fatigue7.Clinical myotonia evaluation8.Change INQoL&MBS.
• Data analysis plan:
  All statistical analyses will be performed using SAS® Version 9.4 or higher.Data will be presented by myotonic disorder type, by age group (18 to 64 years, inclusive, and ≥65 years), other subgroups of interest, and by Namuscla use (newly exposed and prior mexiletine exposure, average dose). Standard descriptive summaries: Descriptive statistics for continuous data: The continuous data will be summarized using the number of observations (n), arithmetic mean, standard deviation, median, minimum value, maximum value and 95% CI. The (n) will be presented with no decimal place, mean and median will be presented up to one decimal place from the original value, SD up to two decimal places from the original value and (min, max) as an original value. Descriptive statistics for categorical data: The categorical variables will be summarized using the frequency count & % for each possible value. The frequencies will be presented up to 0 decimal places and % up to 1 decimal place.