Clinical Trial: Botulinum Toxin to Treat Restless Legs Syndrome

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

Official Title: Pilot Study of Botulinum Toxin Type A for the Treatment of Restless Legs Syndrome

Brief Summary:

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 rep

Detailed Summary:

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
Sponsor: National Institute of Neurological Disorders and Stroke (NINDS)

Current Primary Outcome: Change in Restless Legs Syndrome Rating Scale [ Time Frame: Week 2 and Week 4 for each intervention (vs. baseline) ]

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).


Original Primary Outcome: Primary outcome measure will be the mean change from baseline in the RLS scale at week 2 following placebo/BTX injections

Current Secondary Outcome:

Original Secondary Outcome:

Information By: National Institutes of Health Clinical Center (CC)

Dates:
Date Received: May 25, 2007
Date Started: May 2007
Date Completion:
Last Updated: April 25, 2012
Last Verified: April 2012