Botulinum Toxin to Treat Restless Legs Syndrome

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Fatta Nahab, National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier:
NCT00479154
First received: May 25, 2007
Last updated: April 25, 2012
Last verified: April 2012
  Purpose

This study will test whether botulinum toxin (Botox) may relieve the uncomfortable sensations patients with restless legs syndrome (RLS) experience. RLS is a common movement disorder that causes sensory discomfort and restlessness, most often in the legs, which improves with movement. Although medications are available to treat the disorder, many people experience side effects that prevent them from continuing on the medication. The Food and Drug Administration has approved Botox for other movement disorders and for some cosmetic uses.

People 18 years of age or older with moderate to severe RLS who have been taking RLS medications for more than 6 weeks before entering the study may be eligible to participate. Candidates are screened with a medical history, physical and neurological examinations, blood tests and, for women who can become pregnant, a urine pregnancy test.

Participants are randomly assigned to receive injections of either Botox or placebo (salt water) into up to nine areas of the legs. The correct location of the muscles to be injected is determined by electromyography (EMG), a test that measures the electrical activity of muscles. For surface EMG, electrodes (small metal disks) are filled with a conductive gel and taped to the skin. Needle EMG involves inserting a needle into a muscle. Both methods are used in this study.

At 2 and 4 weeks after the injections, subjects are interviewed by telephone and asked to describe their symptoms, side effects and any improvement they may have noticed. After 12 weeks they return to NIH for injections with the alternate compound; that is, those who received Botox previously are given placebo for the second set of injections, and vice-versa. Subjects are again contacted by telephone 2 and 4 weeks after the injections to report their symptoms, side effects and benefits.


Condition Intervention Phase
Restless Legs Syndrome
Drug: Botulinum Toxin A
Phase 1
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Pilot Study of Botulinum Toxin Type A for the Treatment of Restless Legs Syndrome

Resource links provided by NLM:


Further study details as provided by National Institutes of Health Clinical Center (CC):

Primary Outcome Measures:
  • Change in Restless Legs Syndrome Rating Scale [ Time Frame: Week 2 and Week 4 for each intervention (vs. baseline) ] [ Designated as safety issue: No ]
    Primary outcome measure will be the mean change from baseline in RLS scale at week 2 following placebo/BTX injections. Scoring criteria are: Mild (score 1-10); Moderate (score 11-20); Severe (score 21-30); Very severe (score 31-40).


Enrollment: 6
Study Start Date: May 2007
Study Completion Date: April 2008
Primary Completion Date: April 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Botulinum Toxin A
Injection of onabotulinumtoxinA
Drug: Botulinum Toxin A
Maximum dose of 90 units/leg was injected.
Other Name: onabotulinum toxin
Placebo Comparator: Placebo (saline)
Injection of saline placebo
Drug: Botulinum Toxin A
Maximum dose of 90 units/leg was injected.
Other Name: onabotulinum toxin

Detailed Description:

OBJECTIVE:

To evaluate the efficacy of botulinum toxin type A, (BoNT) for the treatment of primary Restless legs syndrome (RLS). We hypothesize that BoNT will be effective at decreasing the deep sensory discomfort of RLS.

STUDY POPULATION:

This protocol is a proof of principle double-blind randomized placebo-BoNT crossover outpatient pilot study of 6 patients diagnosed with moderate to very severe primary RLS.

DESIGN:

All subjects will be evaluated at the NIH Clinical Center by a study investigator to determine eligibility for participation in this protocol. We will obtain a complete medical history, and perform a neurological examination, along with laboratory screening studies. Subjects eligible to participate will receive baseline ratings using the Restless Legs Rating Scale (RLS-RS). Subjects will then be randomized to receive electromyography (EMG)-guided injections of up to 90 units of BoNT or an equivalent volume of saline in each lower extremity, in symptomatic muscles. Subjects will then receive follow up ratings at week 2 and 4 following each injection. Twelve weeks after receiving the first injection, subjects will crossover to receive the alternative compound with similar follow up ratings.

OUTCOME MEASURES:

The primary outcome measure will be mean change from baseline at 4 weeks post-injection on the RLS-RS for placebo and BoNT, while the other pre specified outcomes will evaluate patient reported Clinical Global Impression of Change (CGI-C) scores for each group, duration of effect, and adverse events. Only descriptive statistics will be performed on this limited data sample.

  Eligibility

Ages Eligible for Study:   18 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria
  • INCLUSION CRITERIA:
  • Age 18 or older.
  • Diagnosed with primary RLS based on presence of a characteristic clinical history and the International restless legs syndrome study group (IRLSSG) diagnostic criteria.
  • A minimum score of 11 on the RLS rating scale (this is equivalent to a minimum rating of moderate severity).
  • If subjects are on medications for RLS, the medication regimen must be stabilized for greater than 6 weeks prior to entering the study.

EXCLUSION CRITERIA:

  • Subjects with any abnormal findings on neurological exam.
  • Subjects with a dermatologic disorder that precludes injections in the legs.
  • Subjects with a positive urine pregnancy test.
  • Subjects without the capacity to give informed consent.
  • Subjects taking aminoglycosides, chloroquine, clindamycin, hydroxychloroquine, magnesium sulfate, quinidine, or an anticoagulant.
  • Subjects with abnormal clinical chemistry, hematology or urine drug screen by laboratory testing.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00479154

Locations
United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
Investigators
Principal Investigator: Fatta Nahab, MD NINDS/NIH
  More Information

Publications:
Responsible Party: Fatta Nahab, Assistant Clinical Investigator, National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier: NCT00479154     History of Changes
Other Study ID Numbers: 070160, 07-N-0160
Study First Received: May 25, 2007
Results First Received: March 14, 2011
Last Updated: April 25, 2012
Health Authority: United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):
Restless Leg Syndrome
Botulinum Toxin
RLS

Additional relevant MeSH terms:
Restless Legs Syndrome
Psychomotor Agitation
Nervous System Diseases
Sleep Disorders, Intrinsic
Dyssomnias
Sleep Disorders
Parasomnias
Mental Disorders
Dyskinesias
Neurologic Manifestations
Psychomotor Disorders
Neurobehavioral Manifestations
Signs and Symptoms
Botulinum Toxins, Type A
Botulinum Toxins
Neuromuscular Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Pharmacologic Actions
Anti-Dyskinesia Agents
Central Nervous System Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on August 28, 2014