Skip to main content
OpenTrials
Recruiting

NCT Number: NCT06862596

Clinical Trial of Mexiletine Hydrochloride for Spinal and Bulbar Muscular Atrophy

The purpose of this clinical trial is to evaluate the efficacy and safety of mexiletine hydrochloride in patients with spinal and bulbar muscular atrophy.

The main questions it aims to answer are:

Does mexiletine hydrochloride improve the ALSFRS-R score in spinal and bulbar muscular atrophy patients?

Participants will:

Take mexiletine hydrochloride or a placebo every day for 3 months Visit the hospital once every 4 weeks for evaluations.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Spinal and Bulbar Muscular Atrophy Bulbo-Spinal Atrophy, X-Linked Central Nervous System Diseases Congenital, Hereditary, and Neonatal Diseases and Abnormalities Genetic Diseases, Inborn Genetic Diseases, X-Linked Heredodegenerative Disorders, Nervous System Motor Neuron Disease Muscular Atrophy, Spinal Nervous System Diseases Neurodegenerative Diseases Neuromuscular Diseases Spinal Cord Diseases

Age range

18 year–80 year

Sex eligibility

Male

Study type

Interventional

Phase

Phase 2 / Phase 3

Primary location

Tokyo University Hospital, Bunkyō City, Japan

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Male patients with a CAG repeat count of 38 or more for the androgen receptor gene in genetic testing and a confirmed diagnosis of SBMA
  • Patients with muscle weakness (limb weakness and atrophy, or bulbar palsy) due to lower motor neuron lesion
  • Patients with a total ALSFRS-R score of ≥ 24 and ≤ 42 at screening
  • Patients who are at least 18 years old and less than 80 years old at the time of consent
  • Patients who give their voluntary written consent after having received adequate information on this study (However, if the patient is unable to sign the consent form due to the condition of the disease, a person equivalent to a regal representative must be present to provide written explanation, the prospective candidate must verbally consent to participate in the study, and a person equivalent to a regal representative must sign the consent form on behalf of the patient. The person who is to be the regal representative may sign the document on his/her behalf, noting the circumstances and his/her relationship to the subject.)

Exclusion criteria

  • Patients who have participated or are participating in a clinical trial within 12 weeks prior to enrollment
  • Patients with a history of hypersensitivity to any component of this drug product
  • Patients with a conduction disturbance (such as second- or third-degree atrioventricular block without a pacemaker, or left bundle branch block)
  • Patients with Brugada-type ECG
  • Patients with severe heart failure or heart disease (myocardial infarction, valvular disease, cardiomyopathy, etc.)
  • Patients with sinus bradycardia (<50 beats/minute)
  • Patients with systolic blood pressure of 90 mmHg or less
  • Patients with serum potassium level less than 3.5 mmol/L
  • Patients on antiarrhythmic drugs
  • Patients on antiepileptic drugs that affect to sodium channels
  • Patients on theophylline
  • Patients on narcotics
  • Patients who used Mexiletine within 1 month prior to enrollment or used Mexiletine for expectations of improvement in symptoms of SBMA
  • Patients with serious complications
  • Patients who cannot agree to use contraception during the study period
  • Other Patients deemed inappropriate by the investigator or subinvestigator

Treatment and study plan

Mexiletine hydrochloride

Drug

Mexiletine hydrochloride 300 mg is administered orally divided into three times a day after meals for 12 weeks.

Placebo

Other

Placebo is administered orally divided into three times a day after meals for 12 weeks.

Primary outcomes

  1. Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) score

    Time frame: at 4weeks

    The ALSFRS-R is a comprehensive severity index comprising 12 items covering bulbar, upper limb, lower limb, and respiratory symptoms to evaluate the ADLs of patients with amyotrophic lateral sclerosis (ALS). Each item is rated on a five-point scale from 0 (worse) to 4 (better), and a total score (miniimum 0point and maximum 48 point) is calculated.

Secondary outcomes

  1. ALSFRS-R Score

    Time frame: up to 12 weeks

    The ALSFRS-R is a comprehensive severity index comprising 12 items covering bulbar, upper limb, lower limb, and respiratory symptoms to evaluate the ADLs of patients with ALS. Each item is rated on a five-point scale from 0 (worse) to 4 (better), and a total score (miniimum 0point and maximum 48 point) is calculated.

  2. Spinal and Bulbar Muscular Atrophy Functional Rating Scale (SBMAFRS) score

    Time frame: up to 12 weeks

    The SBMAFRS is a disease-specific motor function assessment scale for Spinal and Bulbar Muscular Atrophy (SBMA).The SBMAFRS is a comprehensive severity index comprising 14 items covering bulbar, upper limb, lower limb, and respiratory symptoms to evaluate the ADLs of patients. Each item is rated on a five-point scale from 0 (worse) to 4 (better), and a total score (miniimum 0point and maximum 56 point) is calculated.

  3. Grip strength

    Time frame: up to 12 weeks

    Grip strength (kg) is set to evaluate the upper limb motor function of patients with SBMA.

  4. Tongue pressure

    Time frame: up to 12 weeks

    Tongue pressure (kPa) is set to evaluate the bulbar function of patients with SBMA.

  5. Timed walk test (4.6 meters)

    Time frame: up to 12 weeks

    The timed walk test (4.6 meters) is an evaluation index for muscle weakness and atrophy of the lower limbs that measures the walking time (in seconds).

  6. 6-minute walk test

    Time frame: up to 12 weeks

    The 6-minute walk test is an evaluation index for lower limb muscle weakness and muscle atrophy that measures the walking distance (in meters).

  7. Respiratory function test (Forced Vital Capacity (FVC))

    Time frame: up to 12 weeks

    FVC (actual value (L) and predicted rate (%) (%FVC)) is set to evaluate for respiratory function.

  8. Respiratory function test (Peak Expiratory Flow (PEF))

    Time frame: up to 12 weeks

    PEF (actual value (L/sec) and predicted rate (%) (%PEF)) is set to evaluate for respiratory function.

Study contacts

Contact information is provided by the study sponsor or research team.

Masahisa Katsuno, PhD, MD

CONTACT

[email protected]

+81527442389

Shinobu Shimizu, PhD

CONTACT

[email protected]

+81527442942

Sponsors and collaborators

Lead sponsor

Masahisa Katsuno

Other

Registry information

Official study title

A Multicenter, Randomized, Placebo-controlled, Double-blind Clinical Trial: The Efficacy and Safety of Mexiletine Hydrochloride for Amelioration of Motor Dysfunction in Spinal and Bulbar Muscular Atrophy

Acronym: Med-SBMA

Important dates

Study start
2025
Primary completion
2027
Study completion
2027
First posted
Mar 6, 2025
Registry last updated
Apr 16, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.