Restless Leg Syndrome drug, REQUIP, approved by FDA

Main Category: Restless Legs Syndrome
Article Date: 07 May 2005 - 9:00 PDT


The US FDA has approved Requip (ropinirole HCl) Tablets for the treatment of moderate-to-severe primary Restless Legs Syndrome (RLS) in adults, GlaxoSmithKline announced today. Requip is the first and only FDA-approved treatment for those patients with moderate-to-severe primary RLS, a chronic and disruptive neurological condition.

RLS, which encompasses a range of severity that includes mild, moderate and severe symptoms, affects approximately one in ten adults in the U.S. Identified in the early 1940's by neurologist Dr. Karl Ekbom, RLS is characterized by a compelling urge to move the legs and by uncomfortable or sometimes painful sensations in the legs 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. Requip is a second-generation dopamine agonist that directly stimulates dopamine receptors in the brain. Although its exact cause is unknown, researchers believe that the underlying cause of RLS 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.

"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. "With the approval of Requip for moderate-to-severe primary RLS, we're proud to be able to offer effective relief to millions of people who live with this condition, many of whom have suffered for years without treatment."

"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. Thanks to Requip, my symptoms are under control, and I am able to turn my attention back to my family, friends and work, instead of on my RLS."

Requip Proven Effective in Treating Moderate-to-Severe Primary RLS

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. "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. Now there is an approved treatment specifically for moderate-to-severe primary RLS which should help to validate this under-recognized and misunderstood condition."

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 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 moderate in intensity. About RLS In general, many people with RLS report a significant impact on their daily activities. In addition to feeling less alert during the day, RLS sufferers may also have difficulty with activities that require prolonged sitting such as movies, long car rides or airline flights. Difficulty falling asleep may frequently be associated with moderate-to-severe primary RLS.

Women account for approximately two-thirds of RLS sufferers, although RLS occurs in both men and women. RLS is generally a chronic condition, and the frequency of RLS symptoms tends to increase with age. In addition, a genetic component has been suggested for patients with primary RLS. Clinical data demonstrate a positive family history of the disorder in as many as 50 percent of affected individuals. When evaluating patients' symptoms of RLS, it is important for health care providers to rule out other underlying conditions that are associated with secondary RLS symptoms, such as iron deficiency, pregnancy and renal failure. Despite the prevalence of RLS, it frequently remains under-diagnosed. A wide range of other diagnoses, including back pain, depression, arthritis, nocturnal cramps, insomnia and neuropathy have been given to patients who present with symptoms of RLS.

Important Safety Information About Requip

Requip may cause patients to fall asleep or feel very sleepy while doing normal activities such as driving; or to feel faint or dizzy, nauseated or sweaty, when they stand up from sitting or lying down. If patients experience these problems, they should talk to their doctor.

About GlaxoSmithKline

GlaxoSmithKline is one of the world's leading research-based pharmaceutical and healthcare companies.

Source:
Holly Russell
GlaxoSmithKline

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