Boehringer Ingelheim Pharmaceuticals, Inc. Release: Multiple New Studies Strongly Support Efficacy Of Pramipexole In Treating Restless Legs Syndrome

SALT LAKE CITY, June 19 /PRNewswire/ -- Clinical data from new studies involving pramipexole presented at the 20th annual meeting of the Associated Professional Sleep Societies (APSS) demonstrated that treatment with pramipexole significantly improved a broad range of restless legs syndrome (RLS) symptoms. Study results included improved sleep quality, rapid and sustained RLS symptom relief, and enhanced quality of life. The APSS is a joint venture of the American Academy of Sleep Medicine (AASM) and Sleep Research Society (SRS). An application has been submitted to the Food and Drug Administration (FDA) for pramipexole for the treatment of moderate to severe primary RLS.

"These studies support the efficacy and safety of pramipexole as a potential RLS treatment," said lead investigator of one study, John W. Winkelman, MD, PhD, Medical Director, Sleep Health Center, Brigham and Women's Hospital. "It was noteworthy, in one study, that patients' RLS symptoms, as well as their sleep, were significantly improved when taking pramipexole."

About the studies

The first study, a multicenter, randomized, double-blind, placebo- controlled, parallel group study, by Winkelman et al demonstrated that pramipexole significantly improved RLS symptoms in patients with moderate to severe RLS while getting to sleep, during the course of the night, and during the day. Four visual analog scales (VAS) were used to assess RLS severity; before sleep onset, at night time, at daytime, as well as satisfaction with sleep. Patients treated with pramipexole experienced reduced RLS symptom severity while getting to sleep (-41.3mm versus -29.0mm for placebo), in the course of the night (-41.3mm versus -24.6mm for placebo), and during the day (-16.0mm versus -9.2mm for placebo) relative to baseline. In addition, patients taking pramipexole also experienced statistically significant improvements in sleep satisfaction.

Corbin et al presented additional data from the same study demonstrating that in as little as one week pramipexole substantially improved RLS symptoms and was well-tolerated. After one week of therapy, 42.5 percent of patients treated with pramipexole rated themselves "much better" or "very much better" versus 14.1 percent of patients in the placebo group. According to the Patient Global Impression (PGI), a seven-point self rating patient scale utilized in this study, the pramipexole-treated responder rate was significantly higher than placebo (61.4 percent versus 44.7 percent, respectively).

A second randomized, double-blind, parallel-group, multicenter, placebo- controlled study by Trenkwalder et al showed that withdrawal of previously successful treatment with pramipexole led to a prompt worsening of RLS symptoms and reoccurrence of sleep disturbances. In the study, patients switched from treatment with pramipexole to placebo experienced a 43 percent worsening of symptoms compared with a -1 percent change in patients who were maintained on pramipexole treatment. After one week, the worst ratings in the placebo group were observed, indicating a rapid onset of sleep dissatisfaction after withdrawal of pramipexole. Patients who remained on pramipexole experienced sustained symptom relief and sleep satisfaction.

In a second poster on the same study, Hoegl et al showed that patients treated with pramipexole for nine months experienced significant and sustained improvements in quality of life as measured by the Johns Hopkins RLS Quality of Life questionnaire, while those who were switched to placebo after six months of successful treatment experienced a significant worsening of RLS symptoms.

Finally, a third double-blind study by Oertel et al of 345 patients randomized 1:2 to receive either placebo or individually optimized doses of pramipexole two to three hours before bedtime, showed that treatment with pramipexole did not produce daytime sleepiness in patients with RLS, and in fact, significantly reduced sleepiness compared with placebo.

About restless legs syndrome (RLS)

RLS is a common, yet often undiagnosed, neurological sensorimotor disorder. Nearly ten percent of the U.S. adult population is affected by RLS, and approximately 12 million Americans suffer from moderate to severe symptoms. Patients with RLS often experience an urge to move their legs at night due to uncomfortable leg sensations that worsen during periods of rest or inactivity, often interfere with the ability to sleep, and are partially or totally relieved with movement, such as walking or stretching. While symptoms can vary from person to person, they are generally described as an urge to move the legs accompanied by burning, creeping, crawling, aching, tingling, or tugging sensations in the legs. Additionally, people with RLS will often have disruptions in sleeping, which may be caused by periodic limb movements (PLMs). Approximately one-third of sufferers experience symptoms more than twice weekly causing moderate to severe distress.

As a direct result of RLS, patients may experience daytime tiredness, mood disturbance, and inability to perform daily activities, which can have a substantial negative impact on patients' quality of life (QOL). Leg discomfort, sleep disturbance, and fatigue can, in turn, impact daily functioning by affecting a patient's ability to work and participate in social activities and family life. A recent study indicated that more than one third of RLS patients who experienced symptoms at least twice a week reported that their symptoms had a high negative impact on their QOL. In a subanalysis of another study, patients with more severe RLS had lower QOL scores than patients with diabetes, hypertension, other cardiovascular conditions, and osteoarthritis.

Despite many years of research and increased disease recognition, RLS still remains underdiagnosed or misdiagnosed to this day. RLS is actually fairly easy to diagnose with positive answers to the following criteria, which were developed by participants in the RLS Diagnosis & Epidemiology workshop at the National Institutes of Health in collaboration with members of the International Restless Legs Syndrome Study Group (IRLSSG):

- Do you have an urge to move your legs, usually accompanied by uncomfortable leg sensations? - Do your symptoms begin or worsen during rest or inactivity, such as lying down or sitting? - Are your RLS symptoms partially or totally relieved by movement, such as walking or stretching? - Are your RLS symptoms worse in the evening or at night, or do they only occur in the evening and at night? About pramipexole

Pramipexole, a compound from Boehringer Ingelheim research, is approved in the U.S. for the treatment of the signs and symptoms of idiopathic Parkinson's disease. Pramipexole is supported by nearly nine years of real-world experience in the treatment of Parkinson's disease, and approximately 9.1 million prescriptions for pramipexole have been written in the U.S. since its launch in 1997. 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. The most common side effects in clinical trials for RLS were nausea, headache, and tiredness. The most commonly reported adverse events in early and late Parkinson's disease in clinical trials were dizziness, involuntary movement, hallucinations, headache, difficulty falling asleep, sleepiness, and nausea. Patients and caregivers should be informed that impulse control disorders/compulsive behaviors may occur while taking medicines, including pramipexole, to treat Parkinson's disease.

Boehringer Ingelheim Pharmaceuticals, Inc.

Boehringer Ingelheim Pharmaceuticals, Inc., based in Ridgefield, CT, is the largest U.S. subsidiary of Boehringer Ingelheim Corporation (Ridgefield, CT) and a member of the Boehringer Ingelheim group of companies.

The Boehringer Ingelheim group is one of the world's 20 leading pharmaceutical companies. Headquartered in Ingelheim, Germany, it operates globally with 143 affiliates in 47 countries and approximately 37,500 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 2005, Boehringer Ingelheim posted net sales of US $11.8 billion (9.5 billion euro) while spending approximately one-fifth of net sales in its largest business segment, Prescription Medicines, on research and development.

For more information, please visit

Boehringer Ingelheim Pharmaceuticals, Inc.

CONTACT: Kate O'Connor, Public Relations, Boehringer IngelheimPharmaceuticals, Inc., +1-203-791-6250,; or Linda Ruckel, Ketchum PublicRelations, +1-646-935-4044,

Back to news