Requip (ropinirole HCl) tablets are indicated for the treatment of moderate-to-severe primary RLS in adults, said GlaxoSmithKline, the drug's manufacturer.

Although the exact cause of RLS is unknown, researchers believe that it may be related to dopamine, a chemical that carries the signals between nerve cells that control body movement. When the dopamine system does not function properly, it may upset the normal communication of these signals. Requip directly stimulates dopamine receptors in the brain.

Significant Disruption of Daily Activities, Sleep

Identified in the early 1940's by neurologist Dr. Karl Ekbom, RLS affects approximately one in ten adults in the U.S. In addition to a compelling urge to move the legs, it is characterized by sometimes painful sensations, often described as creeping-crawling, tingling, pulling or tightening.

Symptoms of RLS generally occur at rest, such as when sitting, lying or sleeping, and are temporarily relieved by movement. These symptoms can significantly disrupt a patient's sleep and daily activities. People with RLS often have difficulty falling and staying asleep and can feel less alert during the day.

"Throughout our clinical research program for Restless Legs Syndrome, we've had the opportunity to speak with many people who suffer from this condition, and we've heard first-hand about how difficult life can be for them," said Chris Viehbacher, President, U.S. Pharmaceuticals, GlaxoSmithKline.

"For me, the most difficult aspect of living with RLS has been the urge to move my legs during times when I just want to relax or when I am trying to fall asleep," said Mary Ellen Onufrow. "Several times a week I feel very unpleasant sensations in my legs that are difficult to describe, and the only way to get rid of them is to get up and move around. These symptoms had a significant impact on many aspects of my life, including my sleep and my daily activities."

Targets Dopamine Dysfunction

The approval of Requip for moderate-to-severe primary Restless Legs Syndrome is supported by data from four double-blind, randomized, placebo- controlled clinical trials in adults diagnosed with RLS. Patients with RLS secondary to other conditions (e.g. iron deficiency, pregnancy and renal failure) were excluded from the study groups, noted GlaxoSmithKline.

"One of the principal benefits of treatment with Requip is relief of the urge to move the legs," said Dr. William Ondo, Associate Professor of Neurology at Baylor College of Medicine, Houston, Texas. "Requip targets what doctors believe may be an underlying cause of the disorder, which is dysfunction of a system involving the brain chemical dopamine."

In the most recently completed U.S. trial, Requip significantly improved symptoms of moderate-to-severe primary RLS in patients from baseline to week 12, according to two validated measurement tools: the International RLS Rating Scale (IRLS Scale) and Clinical Global Impression-Global Improvement (CGI-I) scale.

Patients taking Requip achieved a significantly greater mean improvement in IRLS Rating Scale total score compared to the placebo group (-13.5 points versus -9.8 points, respectively; p<0.0001), and significantly more patients taking Requip showed a "much improved" or "very much improved" score on the CGI-I scale compared with the placebo group (73.3 percent versus 56.5 percent, respectively; p=0.0006).

In two other similarly designed trials that took place in centers largely outside of the U.S., Requip also significantly improved IRLS Rating Scale and CGI-I scale scores from baseline to week 12.

Long-Term Efficacy, Side Effects

Long-term maintenance of efficacy in the treatment of RLS was demonstrated in a 36-week relapse prevention study. In this trial, patients taking Requip demonstrated a significantly lower relapse rate compared with patients randomized to placebo (32.6 percent vs. 57.8 percent, p=0.0156).

In clinical trials in the treatment of moderate-to-severe primary RLS, the most commonly observed adverse events for Requip (n=496) versus placebo (n=500) were nausea (40 percent versus 8 percent), somnolence (12 percent versus 6 percent), vomiting (11 percent versus 2 percent), dizziness (11 percent versus 5 percent) and fatigue (8 percent versus 4 percent). Occurrences of nausea in clinical trials were generally mild to modera