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Pramipexole Clinical Trial Programme in Restless Legs Syndrome (RLS) Reveals New Significant Results


Studies from pramipexole clinical programme confirm efficacy in treating highly prevalent RLS-associated symptoms, including limb pain and mood disturbance

Ingelheim, Germany, 26 August 2008 – Results from a large pramipexole trial programme in Restless Legs Syndrome (RLS) conducted by Boehringer Ingelheim were presented at the 12th European Federation of Neurological Societies (EFNS) Annual Congress held in Madrid, Spain, from 23 to 26 August. The results of two large Phase IV trials showed that while pramipexole significantly improves the characteristic symptoms of RLS among patients with moderate to severe RLS, it also demonstrated significant beneficial effects on associated symptoms such as limb pain and health-related quality of life, including associated mood disturbance.1,2 Limb pain and mood disturbance are important secondary ailments commonly experienced by RLS patients,3-5 and these studies are the first in which an approved RLS treatment has demonstrated benefits addressing these symptoms in a clinical study in RLS patients.

Study details:
Two combined phase IV double-blind, randomised, 12-week trials assessing the impact of pramipexole on associated pain showed significant improvement in RLS overall and in RLS-associated limb pain in the pramipexole treatment arms (n=381; 0.125-0.75 mg/day) compared with placebo (n=378). (Patients rated pain with a visual analogue scale (VAS) before and after treatment).1

At endpoint, scores on the International RLS Study Group Rating Scale (IRLS) decreased more (i.e. symptoms were reduced) in patients treated with pramipexole than with placebo (adjusted mean of –14.2 vs –8.1, p<0.0001 and –13.4 vs –9.6, p=0.0001 in the respective trials).
Reduction in limb pain was also greater with pramipexole than placebo with a median change of −31.0 vs −11.0 (p<0.0001) and −33.5 vs −11.0 (p<0.0001) in the respective trials.
In a further study assessing the effect of pramipexole on RLS related quality of life (QoL) in RLS patients with mood disturbance2, pramipexole (n=203) demonstrated an overall significant improvement in QoL and associated mood disturbance at four and 12 weeks compared with placebo (n=199).
Improvements in daily activities, physical functioning and vitality are correlated with reductions in RLS symptoms: median changes for pramipexole versus placebo were +17.5 and +10.0 (four weeks, p<0.0001) and +20.0 vs +10.0 (12 weeks, p<0.0001).2
Adjusted mean changes in IRLS total scores, evaluating the effect of treatment on the characteristic RLS symptoms, also improved with pramipexole over placebo: -14.0 vs -8.2 (4 weeks, p<.0001) and –14.2 vs –8.1 (12 weeks; p<0.0001).
A significant correlation was observed in changes in RLS-QoL and IRLS scores (12 weeks, p<0.0001).2
”Many studies have noted the fact that RLS has a far-reaching symptom spectrum that can severely impact and limit several aspects of everyday life. The pramipexole clinical trials reinforce the need for a simple, effective treatment for people with RLS to address these symptoms, including limb pain and associated mood disorder, in addition to the characteristic RLS symptoms. These important new findings reaffirm pramipexole as an effective pharmacological regimen for the treatment of RLS. The studies have proven that pramipexole can offer patient-specific benefits, which combined, can lead to significant improvement of patients’ overall quality of life”, commented Magdolna Hornyak, MD, Assistant Professor, Interdisciplinary Pain Centre, University Hospital, Freiburg, Germany.

The impact of RLS is far-reaching and goes beyond the uncontrollable urge to move one’s legs or the inability to sleep, and, therefore, effective treatments need to address the range of symptoms that limit daily activity experienced by patients. These new data add to the evidence for pramipexole as a simple, effective therapy for patients with moderate to severe RLS.

Please be advised
This release is from Boehringer Ingelheim Corporate Headquarters in Germany. Please be aware that there may be national differences between countries regarding specific medical information, including licensed uses. Please take account of this when referring to the information provided in this document. This press release is not intended for distribution within the U.S.A.

Notes to Editor
About Restless Legs Syndrome (RLS)
Restless Legs Syndrome is a neurological disorder characterised by an uncontrollable urge to move the legs, usually accompanied by unpleasant and sometimes painful sensations in the legs. Restless Legs Syndrome affects up to ten percent of the population worldwide aged between 30 and 79 years6 and around one-third of sufferers experience symptoms more than twice weekly causing moderate to severe distress.5 The motor-restlessness worsens during the evening and night causing difficulty initiating and maintaining sleep. The sleep disruption can lead to excessive daytime sleepiness and compromise work performance. Restless Legs Syndrome also has considerable impact on social activities that require immobility.

About pramipexole
Pramipexole (known under the trade names Mirapexin®, Sifrol®, Mirapex® and Pexola®) is a compound from Boehringer Ingelheim research first approved in 1997 for the treatment of the signs and symptoms of idiopathic Parkinson`s disease, as monotherapy or in combination with levodopa. Pramipexole was approved in 2006 for the symptomatic treatment of moderate to severe idiopathic Restless Legs Syndrome (RLS). Pramipexole is currently marketed in over 70 countries across the globe.

The most commonly reported adverse reactions in clinical trials for Restless Legs Syndrome were nausea, headache, fatigue and dizziness. The most commonly reported adverse reactions in early and late Parkinson’s disease in clinical trials were dizziness, nausea, dyskinesia, hypotension, somnolence, insomnia, hallucination, constipation, headache and fatigue.

Pramipexole may cause patients to fall asleep without any warning, even while doing normal daily activities such as driving. When taking pramipexole hallucinations may occur and sometimes patients may feel dizzy, sweaty or nauseated upon standing up. It should be noted that impulse control disorders/compulsive behaviours may occur while taking medicines to treat Parkinson`s disease, including pramipexole.

About Boehringer Ingelheim
The Boehringer Ingelheim group is one of the world’s 20 leading pharmaceutical companies. Headquartered in Ingelheim, Germany, it operates globally with 135 affiliates in 47 countries and 39,800 employees. Since it was founded in 1885, the family-owned company has been committed to researching, developing, manufacturing and marketing novel products of high therapeutic value for human and veterinary medicine.

In 2007, Boehringer Ingelheim posted net sales of 10.9 billion euro while spending one fifth of net sales in its largest business segment Prescription Medicines on research and development.

Related links: Information Pack on Restless Legs Syndrom

1 Hornyak M et al. Amelioration of Nocturnal Limb Pain by Double-Blind Pramipexole for Restless Legs Syndrome. Presented 24 August 2008, 12th Annual Meeting of the Associated Professional Sleep Societies (EFNS), Madrid, Spain.; Poster # P1300.
2 Montagna P et al. Effect of Pramipexole on Quality of Life (QOL) in Patients With Restless Legs Syndrome (RLS) and Mood Disturbance. Presented 24 August 2008, 12th Annual Meeting of the Associated Professional Sleep Societies (EFNS), Madrid, Spain.; Poster # P1689.
3 Kushida C et al. Burden of Restless Legs Syndrome on health-related quality of life. Qual Life Res 2006; 16(4):617-624.
4 Hening WC et al. Impact, diagnosis and treatment of Restless Legs Syndrome in a primary care population: REST (RLS epidemiology, symptoms and treatment) primary care study. Sleep Med 2004; 5(3):237–246.
5 Allen RP et al. Restless Legs Syndrome prevalence and impact: REST general population study. Arch Intern Med 2005; 165(11):1286-1292.
6 Phillips B et al. Epidemiology of Restless Legs symptoms in adults. Arch Intern Med 2000; 160(14): 137-2141.

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Posted: August 2008