New data presented today from a meta-analysis* of nearly 1,300 Parkinson?s disease (PD) patients, indicate that pramipexole (Mirapexin?/Sifrol?) has a beneficial effect on depressive and motivational symptoms in PD.1 This confirms findings from previously published clinical trials,2,3,4 and is in addition to its established efficacy in controlling motor symptoms. These findings are of particular interest as mood symptoms in PD can affect up to 50 percent of the patient population.1,5 The data were presented at the 10th International Congress of Parkinson?s Disease and Movement Disorders (MDS) in Kyoto, Japan.
?We frequently hear from people living with Parkinson?s disease that it is not necessarily the motor symptoms they find the most challenging,? said Mary Baker, Patron and Immediate Past President, European Parkinson?s Disease Association (EPDA). ?Low mood, concern about the future and lack of motivation can have even more impact on their quality of life and the lives of those who care for them.?
The results of the meta-analysis showed that depressive symptoms of PD (measured using the UPDRS scale) significantly improved in 61.0 percent of patients treated with pramipexole compared to only 40.5 percent of patients treated with placebo.1 Moreover, motivation also significantly improved in 64.8 percent with pramipexole compared to only 42.4 percent treated with placebo.1 These results provide additional insights in the potential anti-depressant effects of pramipexole in treating PD-related mood symptoms – in addition to its efficacy in motor control – suggesting only one medication might be needed to treat the broad spectrum of PD-related symptoms.
Depressive and motivational symptoms are an intrinsic part of Parkinson?s disease and are associated with reduced dopaminergic activity.1 In up to 30 percent of cases, depression may even manifest itself as the first symptom of PD, preceding the onset of motor symptoms.5 Thus, it is a crucial factor in early diagnosis of the condition.
The effect of early versus delayed pramipexole treatment to be explored
Also launched at the MDS Congress today was a new global clinical trial, PROUD (Impact of Pramipexole On Underlying Disease) 6, designed to examine whether there is an advantage to treating PD with pramipexole early after onset of symptoms, in order to slow or postpone future disability i.e. disease modification. 740 patients will be enrolled in this trial with results being expected in March 2008. At present there are no therapies that have been demonstrated clearly to postpone or slow the progressive disability of PD.
?Currently, common practice is to initiate drug therapy for Parkinson?s disease when symptoms have caused disability,? said Anthony Schapira, MD, Professor of Clinical Neurosciences, Royal Free & University College Medical School. ?However, we would like to better understand how best to help patients who present with the symptoms of early PD. Based on our clinical experience to date with pramipexole in all stages of the disease, the study will also help to assess the potential of pramipexole to treat this group of patients.?
The data presented at the MDS Congress confirm pramipexole?s efficacy in treating both the depressive and motivational symptoms in PD as well as the motor symptoms of the condition. In addition, the PROUD trial will investigate its possible disease-modifying effect and help to gain a better understanding of the full potential of pramipexole in treating PD.
About Parkinson?s Disease
Parkinson?s disease is the second most common chronic neurological disorder in older adults after Alzheimer`s. Its worldwide prevalence is estimated to be approximately one to two percent of those over 65 years.6,7 Although traditionally PD is associated with motor symptoms (such as tremor, rigidity, slowed motion, imbalance, shuffling gait, loss of facial expression), the non-motor symptoms, including depressive symptoms, pain, cognitive impairment and sleep disorders can be significant. The symptoms can vary from patient to patient, but worsen over time.
About pramipexole
Pramipexole (known in Europe under the trade names Sifrol? and Mirapexin? and in the U.S.A. as Mirapex?) is a compound from Boehringer Ingelheim research first licensed in 1997 for the treatment of the signs and symptoms of idiopathic Parkinson`s disease, as monotherapy or in combination with levodopa. Pramipexole was licensed in April 2006 throughout the European Union for the symptomatic treatment of moderate to severe idiopathic Restless Legs Syndrome (RLS) and is also approved in Australia, Brazil, Canada, Mexico and others.
The most commonly reported adverse reactions in early and late Parkinson?s disease in clinical trials were dizziness, involuntary movement, postural hypotension, constipation, hallucinations, headache, difficulty falling asleep, sleepiness, nausea and fatigue. The most commonly reported adverse reactions in clinical trials for Restless Legs Syndrome were nausea, headache, and tiredness.
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.
Boehringer Ingelheim
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 almost 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 9.5 billion euro while spending almost one fifth of net sales in its largest business segment Prescription Medicines on research and development.
* The meta-analysis included 7 double-blind, placebo-controlled pramipexole studies which all used Section 1 (mentation, behaviour and mood) of the Unified Parkinson?s Disease Rating Scale (UPDRS).1 Mean treatment was 151 days with pramipexole and 147 days with placebo.1
The UPDRS scale8 is a rating tool that was developed to provide a comprehensive tool to follow the longitudinal course of PD related disability and impairment. The UPDRS is the most commonly used instrument to capture multiple aspects of PD. It assesses both motor disability (part II: activities of daily living) and motor impairment (part III: motor section). In addition, part I addresses mental dysfunction and mood, and Part IV assesses treatment-related motor and non-motor complications. A total score of 199 points is possible. 199 points represent the worst disability and 0 points no disability.
References:
1 Houben J et al. Pramipexole improves depressive and motivational symptoms in Parkinson?s disease. Abstract no. P575, presented at MDS 2006; Kyoto, Japan.
2 Rektorova I et al. Pramipexole and pergolide in the treatment of depression in Parkinson?s disease: a national multicentre prospective randomized study. Eur J Neurol. 2003;10:399-406
3 Barone et al. Pramipexole versus sertraline in the treatment of depression in Parkinson?s disease. A national multicenter parallel-group randomized study. J Neurol 2006;253:601?607
4 Moeller JC et al. Long-term efficacy and safety of pramipexole in advanced Parkinson?s disease: results from a European multicenter trial. Mov Disord. 2005;20:602-610.
5 Byrne R, Chaudhuri, KR. Depression: a key non-motor symptom of Parkinson?s disease. Progress in Neurology and Psychiatry (NY) 2006; 10(5):15-21.
6 Schapira AHV et al. Design of a randomized, placebo-controlled trial of immediate vs deferred pramipexole for early-onset Parkinson?s disease. Abstract no. P511, presented at MDS 2006; Kyoto, Japan.
7 de Rijk MC, Tzourio C, Breteler MM et al. Prevalence of Parkinsonism and Parkinson?s disease in Europe: the EUROPARKINSON Collaborative Study. European Community Concerted Action on the Epidemiology of Parkinson?s disease. J Neurol Neurosurg Psychiatry 1997;62:10?5.
8 Fahn S, Elton RL. Recent Developments in PD. Vol. II; Maximilian Healthcare Information Florham Park, NJ (1987), pp. 153-163, 293-304