Clinical Trial: Dutasteride to Treat Spinal and Bulbar Muscular Atrophy (SBMA)

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional



Official Title: Phase II Clinical Trial to Examine the Efficacy and Safety of Dutasteride in Patients With Kennedy's Disease (Spinal and Bulbar Muscular Atrophy

Brief Summary:

This study will determine if the drug dutasteride can improve weakness, mobility, functioning, nerve function, and quality of life in patients with spinal and bulbar muscular atrophy (SBMA). Patients with this inherited disease have an abnormal androgen receptor protein. The male hormones testosterone and dihydrotestosterone (DHT) bind to this abnormal receptor, causing damage to nerve cells that innervate muscle and leading to weakness. Dutasteride decreases DHT production. Lowering DHT levels may decrease the harmful effects of DHT to the nerves and improve strength in people with SBMA.

Males 18 years of age and older with SBMA who have neurological symptoms and can walk 100 feet (with or without assistive devices) may be eligible for this study. Candidates are screened with a blood test and a review of their medical records and genetic studies.

Participants undergo the following procedures:

  • Blood and urine tests, history and physical examination, assessment of muscle strength
  • Quality-of-life questionnaire
  • Tests to assess functional abilities, such walking up steps, keeping the head up while lying down, and other measures
  • Nerve conduction study and motor unit number estimation to assess nerve damage. A probe placed on the skin delivers small electrical impulses and wires taped to the skin record the impulses.
  • Quantitative muscle testing to measure strength. The subject pushes and pulls levers attached to a gauge. Strength is recorded by a computer.
  • Medication. Participants are divided into two groups. One group is given the study drug, dutasteride; the other receives a