Dutasteride to Treat Spinal and Bulbar Muscular Atrophy (SBMA)
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|ClinicalTrials.gov Identifier: NCT00303446|
Recruitment Status : Completed
First Posted : March 16, 2006
Results First Posted : June 22, 2010
Last Update Posted : January 27, 2011
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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.
|Condition or disease||Intervention/treatment||Phase|
|Kennedy's Disease Spinal and Bulbar Muscular Atrophy||Drug: Dutasteride Drug: Placebo||Phase 2|
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||57 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)|
|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)|
|Study Start Date :||March 2006|
|Actual Primary Completion Date :||December 2009|
|Actual Study Completion Date :||December 2009|
Active Comparator: Dutasteride
Dutasteride 0.5 mg/day
Dutasteride 0.5 mg/day
Other Name: Avodart
Placebo Comparator: Placebo
- Muscle Strength Change From Baseline [ Time Frame: 0, 12, and 24 months ]Quantitative muscle assessment (QMA) was done with a fixed frame dynamometer, a strain gauge tensiometer, and a computer-aided acquisition system. Maximal voluntary isometric muscle contractions were measured twice, the average was calculated, and the results were summed over 22 muscle groups (11 on each side). The total force was scaled for body weight and expressed as percent change from baseline. Measurements were performed at 0, 12, and 24 months. The calculated percent changes at 12 and 24 months are shown.
- Creatine Kinase, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Serum creatine kinase was determined in venous blood samples analyzed at the Department of Laboratory Medicine of the NIH Clinical Center.
- Manual Muscle Testing, Change From Baseline. [ Time Frame: 0, 12, and 24 months ]Manual muscle testing was performed using a modified Medical Research Council (MRC) scale (0=worst, 5=best); the average muscle score was based on 22 muscle groups.
- Adult Myopathy Assessment Tool, Change From Baseline [ Time Frame: 0, 12, and 24 months ]The Adult Myopathy Assessment Tool rates physical function and muscle endurance, with higher scores indicating better performance; it includes 7 timed functional tasks and 6 endurance tasks (0=worst, 45=best).
- Timed 2-minute Walk, Change From Baseline [ Time Frame: 0, 12, and 24 months ]The subjects did the 2-minute walk in a 50-foot (15.2-meter) corridor three times, and the average distance was calculated. The subjects were allowed to use an assistive device and rest between the trials.
- Swallow Score Average, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Modified barium swallow studies were done at 0, 12, and 24 months. Twenty-five domains were assessed, and six were chosen for final analysis based on the abnormal findings in subjects evaluated at baseline: vallecular pooling and repeated-swallow, each assessed with thin liquids, purees, and solids (rated 1-4, abnormal to normal).
- Bulbar Rating Scale, Change From Baseline [ Time Frame: 0, 12, and 24 months ]The Bulbar Rating Scale includes eight domains each rated on a 1-4 scale, abnormal to normal. The original 8-32 point scale was transformed to a 0-100% scale to represent the responses as percentages.
- Sensory Nerve Action Potential Average, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Nerve conduction studies were done on four sensory nerves (median, ulnar, radial, sural), and the amplitudes of the evoked responses were averaged. Loss of amplitude indicates impairment of conduction.
- Median Compound Muscle Action Potential, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Nerve conduction studies were done on the median motor nerve, and the compound muscle action potential amplitude was determined. Loss of amplitude indicates impairment of conduction.
- Peroneal Compound Muscle Action Potential, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Nerve conduction studies were done on the peroneal nerve, and the compound muscle action potential amplitude was determined. Loss of amplitude indicates impairment of conduction.
- Motor Unit Nerve Estimation, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Motor unit number estimation (MUNE) was done with a statistical MUNE program, on the abductor pollicis brevis. All subjects were evaluated on the right side unless severe atrophy produced very low compound muscle action potentials; in this case, the left side was investigated or the abductor digiti minimi was substituted. A decrease in MUNE indicates a loss of motor units.
- Activities of Daily Living, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Subjects rated their daily activity with a modified 9-question Activities of Daily Living (ADL) questionnaire (0-4, fully impaired to normal).
- Medical Outcomes Study 36-item Short Form Version 2 (SF-36v2) Physical Component Summary, Change From Baseline [ Time Frame: 0, 12, and 24 months ]Subjects completed the Medical Outcomes Study Short Form Version 2 (SF-36v2), in which they rated their physical quality of life over the preceding 4 weeks. Raw SF-36v2 scores were converted to norm-based scales and component summaries using the scoring code provided by QualityMetric (mean=50, standard deviation (SD)=10).
- Medical Outcomes Study 36-item Short Form Version 2 (SF-36v2) Mental Component Summary, Percent Change From Baseline [ Time Frame: 0, 12, and 24 months ]Subjects completed the Medical Outcomes Study Short Form Version 2 (SF-36v2), in which they rated their mental quality of life over the preceding 4 weeks. Raw SF-36v2 scores were converted to norm-based scales and component summaries using the scoring code provided by QualityMetric (mean=50, standard deviation (SD)=10), and percent change in the norm-based scale was calculated.
- International Index for Erectile Function (IIEF), Change From Baseline [ Time Frame: 0, 12, and 24 months ]Sexual function was rated using the International Index of Erectile Function (IIEF). The total IIEF score (5-75, worst-best) was reported as the percent maximum (0-100%).
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|Ages Eligible for Study:||18 Years and older (Adult, Older Adult)|
|Sexes Eligible for Study:||Male|
|Accepts Healthy Volunteers:||No|
- Genetically confirmed SBMA
- Neurological symptoms of SBMA
- Ability to ambulate 100 feet with or without the use of assistive devices
- Willingness to participate in all aspects of trial design and follow-up
- Male sex
- Age less than 18 years
- Female sex
- A history of hypersensitivity to dutasteride or 5 alpha-reductase inhibitors.
- Exposure to 5 alpha-reductase inhibitors, anti-androgens, testosterone, or steroids in the preceding 6 months
- Patients who are taking potent cytochrome P450 3A4 (CYP3A4) inhibitors for over 4 weeks
- Patients with any pre-existing liver disease
- Alkaline phosphatase, gamma glutamyl transferase, or direct bilirubin greater than 1.5 times the upper limit of normal
- Alanine aminotransferase or aspartate aminotransferase greater than 1.5 times upper limit of normal in subjects with normal creatine kinase levels
- Creatinine greater than 1.5 times the upper limit of normal
- Platelet count, white blood cell count or hemoglobin below the lower limit of normal
- Other clinically significant medical disease that, in the judgment of the investigators, would expose the patient to undue risk of harm or prevent the patient from completing the study
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00303446
|United States, Maryland|
|National Institutes of Health Clinical Center, 9000 Rockville Pike|
|Bethesda, Maryland, United States, 20892|
|Principal Investigator:||Kenneth Fischbeck, M.D.||NINDS, NIH|
Publications of Results:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
|Responsible Party:||Kenneth H. Fischbeck, M.D./National Institute of Neurological Disorders and Stroke, National Institutes of Health|
|Other Study ID Numbers:||
06-N-0113 ( Other Identifier: NINDS IRB protocol number )
|First Posted:||March 16, 2006 Key Record Dates|
|Results First Posted:||June 22, 2010|
|Last Update Posted:||January 27, 2011|
|Last Verified:||January 2011|
Spinal and Bulbar Muscular Atrophy
Bulbo-Spinal Atrophy, X-Linked
Pathological Conditions, Anatomical
Nervous System Diseases
Muscular Atrophy, Spinal
Spinal Cord Diseases
Central Nervous System Diseases
Heredodegenerative Disorders, Nervous System
Motor Neuron Disease
Genetic Diseases, X-Linked
Genetic Diseases, Inborn
5-alpha Reductase Inhibitors
Steroid Synthesis Inhibitors
Molecular Mechanisms of Pharmacological Action
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs