Dutasteride to Treat Spinal and Bulbar Muscular Atrophy (SBMA)
Status:
Completed
Trial end date:
2009-12-01
Target enrollment:
Participant gender:
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 placebo (sugar pill). All participants take their
assigned medication once a day for 24 months.
- Follow-up evaluations. Every 6 months for 2 years, participants return to NIH to repeat
the tests described above to determine the effects of the dutasteride. Nerve and
quantitative muscle testing is not done at the 6- and 18-month visits.
- In addition to their follow-up appointments here at the NIH every 6 months, participants
will also have blood tests and a physical examination performed after 3, 9, 15 and 21
months of treatment by the patient's local physician.
Phase:
Phase 2
Details
Lead Sponsor:
National Institute of Neurological Disorders and Stroke (NINDS)