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Background and purpose Drugs able to counteract progressive multiple sclerosis (MS) represent a largely unmet therapeutic need. Even though the pathogenesis of disease evolution is still obscure, accumulating evidence indicates that mitochondrial dysfunction plays a causative role in neurodegeneration and axonopathy in progressive MS patients. Here, we investigated the effects of dexpramipexole, a compound with a good safety profile in humans and able to sustain mitochondria functioning and energy production, in a mouse model of progressive MS. Experimental approach Female non-obese diabetic mice were immunized with MOG35-55 . Functional, immune and neuropathological parameters were analysed during disease evolution in animals treated or not with dexpramipexole. The compound's effects on bioenergetics and neuroprotection were also evaluated in vitro. Key results We found that oral treatment with dexpramipexole at a dose consistent with that well tolerated in humans delayed disability progression, extended survival, counteracted reduction of spinal cord mitochondrial DNA content and reduced spinal cord axonal loss of mice. Accordingly, the drug sustained in vitro bioenergetics of mouse optic nerve and dorsal root ganglia and counteracted neurodegeneration of organotypic mouse cortical cultures exposed to the adenosine triphosphate-depleting agents oligomycin or veratridine. Dexpramipexole, however, was unable to affect the adaptive and innate immune responses both in vivo and in vitro. Conclusion and implication The present findings corroborate the hypothesis that neuroprotective agents may be of relevance to counteract MS progression and disclose the translational potential of dexpramipexole to treatment of progressive MS patients as a stand-alone or adjunctive therapy.

Background and purpose Gamma oscillations are fast rhythmic fluctuations of neuronal network activity ranging from 30 to 90 Hz that establish a precise temporal background for cognitive processes such as perception, sensory processing, learning, and memory. Alterations of gamma oscillations have been observed in schizophrenia and are suggested to play crucial roles in the generation of positive, negative, and cognitive symptoms of the disease. Experimental approach In this study, we investigated the effects of the novel antipsychotic cariprazine, a D3 -preferring dopamine D3 /D2 receptor partial agonist, on cholinergically induced gamma oscillations in rat hippocampal slices from treatment-naive and MK-801-treated rats, a model of acute first-episode schizophrenia. Key results The D3 receptor-preferring agonist pramipexole effectively decreased the power of gamma oscillations, while the D3 receptor antagonist SB-277011 had no effect. In treatment-naive animals, cariprazine did not modulate strong gamma oscillations but slightly improved the periodicity of non-saturated gamma activity. Cariprazine showed a clear partial agonistic profile at D3 receptors at the network level by potentiating the inhibitory effects when the D3 receptor tone was low and antagonizing the effects when the tone was high. In hippocampal slices of MK-801-treated rats, cariprazine allowed stabilization of the aberrant increase in gamma oscillation power and potentiated resynchronization of the oscillations. Conclusion and implications Data from this study indicate that cariprazine stabilizes pathological hippocampal gamma oscillations, presumably by its partial agonistic profile. The results demonstrate in vitro gamma oscillations as predictive biomarkers to study the effects of antipsychotics preclinically at the network level.

Background The appropriate timing of dopaminergic treatment initiation in Parkinson's disease (PD) remains a matter of debate. The primary objective of this study was to determine whether earlier initiation of treatment was associated with less worsening of total UPDRS scores over 48 months. Methods We performed a secondary analysis of data from the CALM-PD (Comparison of the Agonist Pramipexole With Levodopa on Motor Complications of Parkinson's Disease) trial to examine the associations between years since diagnosis and 48-month changes in total and component UPDRS scores, Parkinson's Disease Quality of Life Scale (PDQUALIF) score, and the EuroQol-5D visual analogue scale (VAS) score. Results There were no associations between years since PD diagnosis and 48-month changes in total UPDRS, component UPDRS scores, PDQUALIF score, or EuroQol-5D VAS score. Conclusion Earlier treatment was not associated with improved long-term outcomes in this secondary analysis. Prospective studies are required to determine the appropriate timing of initiation of dopaminergic treatment to inform clinical practice.

BACKGROUND: Dopamine receptor 2 (DRD2) and ghrelin receptor (GHSR1a) agonists both stimulate defecation by actions at the lumbosacral defecation center. Dopamine is in nerve terminals surrounding autonomic neurons of the defecation center, whereas ghrelin is not present in the spinal cord. Dopamine at D2 receptors generally inhibits neurons, but at the defecation center, its effect is excitatory. METHODS: In vivo recording of defecation and colorectal propulsion was used to investigate interaction between DRD2 and GHSR1a. Localization studies were used to determine sites of receptor expression in rat and human spinal cord. KEY RESULTS: Dopamine, and the DRD2 agonist, quinpirole, directly applied to the lumbosacral cord, caused defecation. The effect of intrathecal dopamine was inhibited by the GHSR1a antagonist, YIL781, given systemically, but YIL781 was not an antagonist at DRD2. The DRD2 agonist, pramipexole, administered systemically caused colorectal propulsion that was prevented when the pelvic nerves were cut. Drd2 and Ghsr were expressed together in autonomic preganglionic neurons at the level of the defecation centers in rat and human. Behaviorally induced defecation (caused by water avoidance stress) was reduced by the DRD2 antagonist, sulpiride. We had previously shown it is reduced by YIL781. CONCLUSIONS AND INFERENCES: Our observations imply that dopamine is a transmitter of the defecation pathways whose actions are exerted through interacting dopamine (D2) and ghrelin receptors on lumbosacral autonomic neurons that project to the colorectum. The results explain the excitation by dopamine agonists and the conservation of GHSR1a in the absence of ghrelin.

The gene that encodes the protein tyrosine phosphatase D (PTPRD) may be related to brain circuits associated with sleep, and has been seen as an interesting molecule, a "druggable" drug target. This gene is a potential candidate for increasing therapeutic advances in restless legs syndrome, a sleep-related movement disorder, that manifests as an uncontrollable desire to move limbs (legs) to relieve uncomfortable sensations. Changes in the PTPRD gene expression may increase the chance of developing this syndrome. Treatment with pramipexole is used in restless legs syndrome. This study aims to verify the effect of treatment with pramipexole on the PTPRD expression, as well as on the sleep pattern in an animal model for restless legs syndrome. For this, an animal model of sleep-related movement disorders (spontaneously hypertensive rats) was distributed in groups: (a) spontaneously hypertensive rats-control; (b) spontaneously hypertensive rats-pramipexole (0.125 mg kg-1 for 4 weeks). The analyses of PTPRD gene and protein expression were performed in the striatum and spinal cord by quantitative real-time polymerase chain reaction and indirect enzyme-linked immunosorbent assay, respectively. Electrocorticographic and electromyographic analyses were performed. There was no difference in the PTPRD mRNA levels, as well as in the protein levels, although a tendency has been observed for decreased gene expression in the striatum and increased protein expression in the spinal cord in the spontaneously hypertensive rats-pramipexole group. Pramipexole improved the animals' sleep pattern. Thus, the treatment with pramipexole in the evaluated dose and time tended to alter the expression of the PTPRD protein in the spinal cord, in addition to significantly improving the sleep pattern.

Impulsive-compulsive spectrum disorders are associated with dopamine agonist therapy in some patients. These untoward outcomes occur with direct-acting, full and partial agonists at D2 dopamine family receptors. The disorders typically emerge during chronic treatment, and exhibit common features that are independent of the neurological or psychiatric pathology for which the initial therapy was indicated. It is well-documented that the brain is 'plastic', changing in response to alterations to internal factors (e.g., disease processes), as well as external factors (e.g., therapies). The complexities of these clinical scenarios have eluded a clear depiction of the neurobiology for impulsive-compulsive spectrum disorders and engendered considerable debate regarding the mechanistic underpinnings of the disorders. In this opinion, we use pharmacological concepts related to homeostatic compensation subsequent to chronic receptor activation to provide a unifying construct. This construct helps explain the occurrence of impulsive-compulsive spectrum disorders across disease states, and during therapy with full and partial agonists.

The objective of the current review was to update the previous evidence-based medicine review of treatments for restless legs syndrome published in 2008. All randomized, controlled trials (level I) with a high quality score published between January 2007 and January 2017 were reviewed. Forty new studies qualified for efficacy review. Pregabalin, gabapentin enacarbil, and oxycodone/naloxone, which did not appear in the previous review, have accrued data to be considered efficacious. Likewise, new data enable the modification of the level of efficacy for rotigotine from likely efficacious to efficacious. Intravenous ferric carboxymaltose and pneumatic compression devices are considered likely efficacious in idiopathic restless legs syndrome. Bupropion and clonidine were reviewed, but the lack of data determined a rating of insufficient evidence for efficacy. The following interventions continue to be considered efficacious as in 2008: levodopa, ropinirole, pramipexole, cabergoline, pergolide, and gabapentin. Bromocriptine, oxycodone, carbamazepine, and valproic acid are considered likely efficacious. Oral iron is nonefficacious in iron-sufficient subjects, but its benefit for patients with low peripheral iron status has not been adequately evaluated. Restless legs syndrome augmentation has been identified as a significant long-term treatment complication for pramipexole more than pregabalin and possibly for all dopaminergic agents more than α2δ ligands. Therefore, special monitoring for augmentation is required for all dopaminergic medications as well as tramadol. Other drugs also require special safety monitoring: cabergoline, pergolide, oxycodone, methadone, tramadol, carbamazepine, and valproic acid. Finally, we also highlighted gaps and needs for future clinical research and studies of restless legs syndrome. © 2018 International Parkinson and Movement Disorder Society.

Author(s): Lai, Yuan-Yang; Cheng, Yu-Hsuan; Hsieh, Kung-Chiao; Nguyen, Darian; Chew, Keng-Tee; Ramanathan, Lalini; Siegel, Jerome M | Abstract: BackgroundAbnormal striatal dopamine transmission has been hypothesized to cause restless legs syndrome. Dopaminergic drugs are commonly used to treat restless legs syndrome. However, they cause adverse effects with long-term use. An animal model would allow the systematic testing of potential therapeutic drugs. A high prevalence of restless legs syndrome has been reported in iron-deficient anemic patients. We hypothesized that the iron-deficient animal would exhibit signs similar to those in restless legs syndrome patients.MethodsAfter baseline polysomnographic recordings, iron-deficient rats received pramipexole injection. Then, iron-deficient rats were fed a standard rodent diet, and polysomnographic recording were performed for 2 days each week for 4 weeks.ResultsIron-deficient rats have low hematocrit levels and show signs of restless legs syndrome: sleep fragmentation and periodic leg movements in wake and in slow-wave sleep. Iron-deficient rats had a positive response to pramipexole treatment. After the iron-deficient rats were fed the standard rodent diet, hematocrit returned to normal levels, and sleep quality improved, with increased average duration of wake and slow-wave sleep episodes. Periodic leg movements decreased during both waking and sleep. Hematocrit levels positively correlated with the average duration of episodes in wake and in slow-wave sleep and negatively correlated with periodic leg movements in wake and in sleep. Western blot analysis showed that striatal dopamine transporter levels were higher in iron-deficient rats.ConclusionsThe iron-deficient rat is a useful animal model of iron-deficient anemic restless legs syndrome. © 2017 International Parkinson and Movement Disorder Society.

Background Rasagiline and pramipexole act to improve striatal dopaminergic transmission in PD via distinct and potentially synergistic mechanisms. We performed a placebo-controlled study to determine whether 2 doses of a novel slow-release, low-dose combination of rasagiline and pramipexole (P2B001) are effective and have a good safety profile in patients with early untreated PD. Methods Previously untreated patients with early PD were randomized (1:1:1) to once-daily treatment with P2B001 (0.3 mg pramipexole/0.75 mg rasagiline), P2B001 (0.6 mg pramipexole/0.75 mg rasagiline) or placebo in a 12-week multicenter double-blind, placebo-controlled trial. The primary endpoint was the change from baseline to final visit in Total-UPDRS score versus placebo. Secondary measures included responder analyses of patients achieving ≥4 UPDRS point reduction, and changes in Parkinson Disease Quality of Life Scale–39 and UPDRS activities of daily living and motor scores. Results A total of 149 participants were randomized and 136 (91.3%) completed the study. Adjusted mean change from baseline to final visit versus placebo in Total-UPDRS score was −4.67 ± 1.28 points for the P2B001 0.6/0.75 mg group (P = .0004) and −3.84 ± 1.25 points for the 0.3/0.75 mg group (P = .003). Significant benefits were also observed for both doses in the responder analysis (P = .0002 and P = .0001), Parkinson Disease Quality of Life Scale–39 scores (P = .05 and P = .01), and the UPDRS motor (P = .02 and P = .006) and activities of daily living (P = .005 and P = .0004) subscores. Adverse events of P2B001 were comparable to placebo apart from transient nausea and somnolence, which were more common with P2B001 treatment. Conclusions P2B001 offers a promising treatment option for patients with early PD with good clinical efficacy and a low risk of adverse events. © 2017 International Parkinson and Movement Disorder Society

Antihistamines are known risk factors for restless legs syndrome (RLS). However, reports on RLS associated with fexofenadine or its combinations are rare. Here, we report a 30‐year‐old woman with RLS that was induced by fexofenadine/pseudoephedrine. She had been taking fexofenadine/pseudoephedrine for three months and felt a strong urge to move her legs at night, which was relieved by movement. Her condition improved by taking pramipexole, which she discontinued subsequently because of dizziness. One month later, she quitted taking fexofenadine/pseudoephedrine, after which her symptoms disappeared a week later. This case study demonstrates that RLS can be induced by fexofenadine/pseudoephedrine and we should always consider the possibility of drug‐induced RLS.

Objective Several depressed patients do not respond to traditional antidepressants. Our aim was to systematically review the effectiveness and safety of pramipexole in unipolar and bipolar depression. Methods We conducted a systematic review of randomized clinical trials (RCTs) and observational studies on pramipexole for patients with major depressive episodes, following PRISMA guidelines. Our primary outcome measure was treatment response at endpoint. The study protocol was registered on PROSPERO: CRD42018108699. Results We found five RCTs, three open‐label trials and five observational studies, with 504 participants (57% women; mean age, 45.3 years; mean sample size, 39; median duration of treatment, 8 weeks; mean follow‐up duration, 45 weeks; mean maximum dose, 1.62 mg). We found an overall short‐term response rate of 52.2% and remission rate of 36.1%, and an overall long‐term response rate of 62.1% and remission rate of 39.6%. In RCTs, patients treated with pramipexole had a superior response rate compared with placebo (RR: 1.77; 95% CI: 1.11–2.82) and similar to SSRIs (RR: 0.93; 95% CI: 0.44–1.95). Acceptability and tolerability were good, with nausea being the most frequent side‐effect. Conclusion Our study found some evidence for an effect of pramipexole for the treatment of major depressive episodes.

Comparative analyses of the efficacies of dopaminergic agonists (pramipexole, ropinirole, and rotigotine patch) and α-2-δ ligands (gabapentin enacarbil and pregabalin) for treatment of primary restless leg syndrome (RLS) are lacking because of the few head-to-head clinical trials. A model-based meta-analysis approach was employed to quantitatively compare the efficacies of these 5 first-line RLS drugs. Longitudinal efficacy data of RLS drugs were collected from published eligible literature. Mean changes in both the International Restless Leg Syndrome Study Group (IRLS) rating scale and Clinical Global Impression Improvement (CGI-I) scale response rate were analyzed. A study-level population pharmacodynamic model was used to fit the dose-effect relationship and to describe the therapeutic effect over time for RLS drugs and placebo, and the typical efficacies of these drugs were compared. The onset of action was rapid for RLS drugs. In the placebo group, typical maximum IRLS reduction (Emax,IRLS ) and CGI-I response rate (Emax,CGI-I ) were -9.34 points and 48.2%, respectively. After deducting placebo effects, we found that the baseline IRLS score was significantly correlated with the Emax,IRLS of dopaminergic agonists. Typical Emax,IRLS of dopaminergic agonists was expressed as - 7.7 - 0.682 × ( baseline IRLS score - 24 ) points. Typical Emax,IRLS values of pregabalin and gabapentin enacarbil were -5.95 points and -4.00 points, respectively. The therapeutic effect of dopaminergic agonists was found to be associated with baseline symptom severity. In RLS patients with more severe symptoms, the therapeutic effect of dopaminergic agonists tended to be better than that of α-2-δ ligands.

Over a period of more than 50 years, the symptomatic treatment of the motor symptoms of Parkinson disease (PD) has been optimized using pharmacotherapy, deep brain stimulation, and physiotherapy. The arsenal of pharmacotherapies includes L-Dopa, several dopamine agonists, inhibitors of monoamine oxidase (MAO)-B and catechol-o-methyltransferase (COMT), and amantadine. In the later course of the disease, motor complications occur, at which stage different oral formulations of L-Dopa or dopamine agonists with long half-life, a transdermal application or parenteral pumps for continuous drug supply can be subscribed. Alternatively, the patient is offered deep brain stimulation of the subthalamic nucleus (STN) or the internal part of the globus pallidus (GPi). For a more efficacious treatment of motor complications, new formulations of L-Dopa, dopamine agonists, and amantadine as well as new MAO-B and COMT inhibitors are currently tested in clinical trials, and some of them already yielding positive results in phase 3 trials. In addition, non-dopaminergic agents have been tested in the early clinical phase for the treatment of motor fluctuations and dyskinesia, including adenosine A2A antagonists (istradefylline, preladenant, and tozadenant) and modulators of the metabolic glutamate receptor 5 (mGluR5 - mavoglurant) and serotonin (eltoprazine) receptors. Recent clinical trials testing coenzyme Q10, the dopamine agonist pramipexole, creatine monohydrate, pioglitazone, or AAV-mediated gene therapy aimed at increasing expression of neurturin, did not prove efficacious. Treatment with nicotine, caffeine, inosine (a precursor of urate), and isradipine (a dihydropyridine calcium channel blocker), as well as active and passive immunization against α-synuclein and inhibitors or modulators of α-synuclein-aggregation are currently studied in clinical trials. However, to date, no disease-modifying treatment is available. We here review the current status of treatment options for motor and non-motor symptoms, and discuss current investigative strategies for disease modification. This review provides basic insights, mainly addressing basic scientists and non-specialists. It stresses the need to intensify therapeutic PD research and points out reasons why the translation of basic research to disease-modifying therapies has been unsuccessful so far. The symptomatic treatment of the motor symptoms of Parkinson disease (PD) has been constantly optimized using pharmacotherapy (L-Dopa, several dopamine agonists, inhibitors of monoamine oxidase (MAO)-B and catechol-o-methyltransferase (COMT), and amantadine), deep brain stimulation, and physiotherapy. For a more efficacious treatment of motor complications, new formulations of L-Dopa, dopamine agonists, and amantadine as well as new MAO-B and COMT inhibitors are currently tested in clinical trials. Non-dopaminergic agents have been tested in the early clinical phase for the treatment of motor fluctuations and dyskinesia. Recent clinical trials testing coenzyme Q10, the dopamine agonist pramipexole, creatine monohydrate, pioglitazone, or AAV-mediated gene therapy aimed at increasing expression of neurturin, did not prove efficacious. Treatment with nicotine, caffeine, and isradipine – a dihydropyridine calcium channel blocker – as well as active and passive immunization against α-synuclein and inhibitors of α-synuclein-aggregation are currently studied in clinical trials. However, to date, no disease-modifying treatment is available for PD. We here review the current status of treatment options and investigative strategies for both motor and non-motor symptoms. This review stresses the need to intensify therapeutic PD research and points out reasons why the translation of basic research to disease-modifying therapies has been unsuccessful so far. This article is part of a special issue on Parkinson disease.

Sleep bruxism bears several similarities to restless legs syndrome, and a link to changes in central dopamine activity has been considered in both conditions. The dopamine agonist pramipexole is currently indicated for the symptomatic treatment of restless legs. The effect of pramipexole on sleep bruxism was investigated in subjects with 'probable bruxism' recruited at the Orofacial Pain Clinic. Thirteen patients underwent polysomnographic recordings, including bilateral masseter electromyographic activity. Following habituation to the recording equipment, a baseline registration was used to confirm bruxism [total episodes per hour, mean 11.3 (6.3)]. Following randomisation, subjects received no treatment or pramipexole titrated from 0.09 to 0.54 mg, o.d., for 3 weeks according to a crossover procedure. A polysomnographic-electromyographic registration was performed at the end of each period. Pramipexole was associated with more frequent awakenings and a reduction in rapid eye movement sleep (both P ≤ 0.02). Sleep apnea decreased marginally after pramipexole (apnea-hypopnea index 17.1 compared with control 21.5, P ≤ 0.05). The number of bruxism episodes, phasic, tonic and mixed per hour, remained unchanged after pramipexole [total episodes per hour 12.7 (8.5) and 9.8 (5.2) during pramipexole and control conditions, respectively]. It is concluded, from this pilot study, that sleep bruxism is not affected by the dopaminergic agent, pramipexole.

A hydrophilic monolithic CEC column was prepared by thermal copolymerization of zwitterionic monomer 2-methacryloyloxyethyl phosphorylcholine (MPC), pentaerythritol triacrylate (PETA), either methacrylatoethyl trimethyl ammonium chloride (META) or sodium 2-methylpropene-1-sulfonate (MPS) in a polar binary porogen consisting of methanol and THF. A typical hydrophilic interaction LC retention mechanism was observed for low-molecular weight polar compounds including amides, nucleotides, and nucleosides in the separation mode of hydrophilic interaction CEC, when high content of ACN (>60%) was used as the mobile phase. The effect of the electrostatic interaction between the analytes and the stationary phase was found to be negligible. The poly(MPC-co-PETA-co-META or MPS) monolithic columns have an average column efficiency of 40 000 plates/m and displayed with a satisfactory repeatability in terms of migration time and peak areas. Finally, the column was successfully applied to determine the impurities of a positively charged drug pramipexole which are often separated by ion pair RP chromatography due to their high hydrophilicity. All four components can be baseline separated within 5 min with BGE consisting of ACN/20 mM ammonium formate buffer (pH 3.0; 80/20).

Background Knowledge of possible cardiovascular risks from Parkinson's disease (PD) medications is critical to informing safe and effective treatment decisions. The objective of our study was to determine whether PD patients treated with nonergot dopamine agonists (DAs) are at increased risk of adverse cardiovascular or cerebrovascular outcomes, relative to PD patients receiving other treatments. Methods Matched case-control studies were conducted within a cohort of 14,122 inpatients receiving treatment for PD who were identified in the Cerner Health Facts database. Primary outcomes were associations between nonergot DA use and diagnosis of adverse cardiovascular events (acute myocardial infarction, heart failure [HF], hypotension, and valvulopathy). Secondary outcomes included associations between nonergot DA use and diagnosis of adverse cerebrovascular events (cerebrovascular accident and ischemic stroke) and odds of significant exposure-outcome relationships by patient factors. Results HF was the only adverse event that demonstrated a significant association with nonergot DA use. Individuals treated with pramipexole were more likely to be diagnosed with HF, relative to no use (adjusted odds ratio [AOR]: 1.28; 95% confidence interval [CI]: 1.07–1.53). The association between pramipexole and HF was greater among individuals treated with pramipexole monotherapy (relative to levodopa monotherapy) (AOR, 1.50; 95% CI: 1.09–2.06). Compared to nonusers, men and older individuals treated with pramipexole were more likely to be diagnosed with HF. Conclusions Results from our study suggest an association between pramipexole use and HF. Findings warrant replication; however, individuals with PD and independent risk factors for, or a history of, HF may benefit from limited use of this drug.

Two male siblings from a consanguineous union presented in early infancy with marked truncal hypotonia, a general paucity of movement, extrapyramidal signs and cognitive delay. By mid-childhood they had made little developmental progress and remained severely hypotonic and bradykinetic. They developed epilepsy and had problems with autonomic dysfunction and oculogyric crises. They had a number of orthopaedic problems secondary to their hypotonia. Cerebrospinal fluid (CSF) neurotransmitters were initially normal, apart from mildly elevated 5-hydroxyindolacetic acid, and the children did not respond favourably to a trial of levodopa-carbidopa. The youngest died from respiratory complications at 10 years of age. Repeat CSF neurotransmitters in the older sibling at eight years of age showed slightly low homovanillic acid and 5-hydroxyindoleacetic acid levels. Whole-exome sequencing revealed a novel mutation homozygous in both children in the monoamine transporter gene SLC18A2 (p.Pro237His), resulting in brain dopamine-serotonin vesicular transport disease. This is the second family to be described with a mutation in this gene. Treatment with the dopamine agonist pramipexole in the surviving child resulted in mild improvements in alertness, communication, and eye movements. This case supports the identification of the causal mutation in the original case, expands the clinical phenotype of brain dopamine-serotonin vesicular transport disease and confirms that pramipexole treatment may lead to symptomatic improvement in affected individuals.

Cotard's syndrome is a relatively rare condition that involves a delusion of negation in which an individual believes he or she has lost his or her soul, is dead, or is without functional body systems. This syndrome is observed in various neuropsychiatric disorders but most commonly in mood disorders. Pramipexole has often been used in the adjunctive treatment of both bipolar and unipolar depression, and it is known to cause rare but serious adverse effects such as compulsive behaviours in the treatment of Parkinson's disease. Here we report a case of Cotard's syndrome in treatment-resistant major depression associated with abnormal behaviours that might be caused by pramipexole. In the present case, the patient's abnormal behaviours gradually disappeared about 2 months after the discontinuation of pramipexole. The hypoperfusion in the bilateral parieto-occipital lobe found on single-photon emission computed tomography suggests the presence of Lewy body disease pathology. Nonetheless, the patient's abnormal behaviours disappeared after the discontinuation of pramipexole, indicating that they are mainly attributable to pramipexole treatment. However, the possible existence of Lewy body pathology could facilitate the emergence of abnormal behaviours after treatment with pramipexole. The patient's abnormal behaviours, such as eating other patients' food and taking her medicine before the scheduled time, might differ from typical compulsive behaviours induced by pramipexole (such as pathological gambling and hypersexuality), but they could be regarded as disinhibition. Therefore, we should follow up on the clinical course of this case carefully through neuroimaging investigation and neurocognitive assessment.

Parkinson's disease (PD) is an increasingly prevalent and progressively disabling neurodegenerative disease. The impact of PD on patients and their families as well as its burden on health care systems could be substantially reduced by disease-modifying therapies that slow the rate of neurodegeneration or stop the disease process. Multiple agents have been studied in clinical trials designed to assess disease modification in PD, but all have failed. Over the last 3 years, clinical trials investigating the potential of adeno-associated virus serotype 2 (AAV)-neuturin, coenzyme Q10, creatine, pramipexole, and pioglitazone reported negative findings or futility. Despite these disappointments, progress has been made by expanding our understanding of molecular pathways involved in PD to reveal new targets, and by developing novel animal models of PD for preclinical studies. Currently, at least eight ongoing clinical trials are testing the promise of isradipine, caffeine, nicotine, glutathione, AAV2-glial cell-line derived neurotrophic factor (GDNF), as well as active and passive immunization against α-synuclein (α-Syn). In this review, we summarize the clinical trials of disease-modifying therapies for PD that were published since 2013 as well as clinical trials currently in progress. We also discuss promising approaches and ongoing challenges in this area of PD research.

Background Parkinson's disease affects 1% of the population older than 60 years. Motor symptoms can be difficult to treat in end-stage disease, leading to the use of therapies with less favourable adverse effect profiles. Aim To promote awareness of the risks associated with the off-label use of methylphenidate for hypokinesia in Parkinson's disease patients with cardiovascular risk factors. Clinical details A 70-year-old Caucasian non-smoking male presented to the hospital with chest pain and inferior ST segment elevation 2 months after commencing methylphenidate for gait hypokinesia. His past medical history was significant for end-stage Parkinson's disease with associated psychosis, and ischaemic heart disease with previous myocardial infarction. Relevant therapies included levodopa, benserazide, amantadine, pramipexole, quetiapine, atorvastatin and perindopril. Outcomes The patient received a drug eluting stent to the circumflex artery, followed by a staged percutaneous coronary intervention to the left anterior descending artery. Methylphenidate was discontinued on day 2 post myocardial infarction in light of published data indicating an increased risk of myocardial infarction with methylphenidate use. Methylphenidate is known to stimulate catecholamine release, thereby increasing the risk of ischaemic cardiovascular events by increasing myocardial oxygen demand. Conclusion This is the first reported case to describe methylphenidate use in Parkinson's disease complicated by a myocardial infarction. This case, in conjunction with other published literature, suggests that the use of methylphenidate for this novel indication must be carefully considered for each individual, and avoided in those with cardiovascular risk factors or known ischaemic heart disease.

Dopamine agonist withdrawal syndrome (DAWS) has been reported in patients with Parkinson's disease (PD) who rapidly decrease or stop their dopamine agonist (DA) treatment. Retrospective studies suggest a high prevalence of DAWS (14%–18%) in PD, but there are no prospective studies. We report data from the first pilot European multicenter prospective study addressing the frequency of probable DAWS (Rabinak‐Nirenberg criteria) in PD patients. The self‐completed Nonmotor Symptoms Questionnaire (which addresses the core features of DAWS) was administered at clinical follow‐up at 1 month in 51 patients (33 male; mean age: 73.0 ± 9.9 years; PD duration: 12.2 ± 6.3 years) who had discontinued dopamine agonists. Twelve out of fifty‐one patients (24%) met clinical criteria for DAWS, the most common symptoms of which were anxiety (91.7%), pain (50%), sweating (41.7%), and anhedonia (16.7%), after the withdrawal of a DA (ropinirole, pramipexole, or cabergoline). In this first prospective evaluation of DAWS in the clinic, preliminary data indicate a high rate after discontinuation of a range of DAs, particularly in the context of impulse control disorders. Larger, controlled studies are required to establish a definitive management pathway.

In treating Parkinson's disease with dopaminergic agonists, such as pramipexole, ropinirole, pergolide, rotigotine, apomorphine, or bromocriptine, it has been observed that a significant number of patients develop impulse-control disorders, such as compulsive shopping, pathological gambling, or hypersexuality. Because the dopamine agonists have high affinities for the dopamine D2 and D3 receptors, the drug dissociation constants of these drugs at the functional high-affinity states of these receptors, namely D2High and D3High, were compared. The data show that, compared to the other dopamine agonist drugs, pramipexole has a relatively high selectivity for the dopamine D3 receptor, as compared to D2, suggesting that the D3 receptor may be a primary target for pramipexole. There is a trend showing that the proportion of impulse-control disorders is related to the selectivity for D3 receptors over D2 receptors, with pramipexole having the highest association with, or frequency of, impulse-control disorders. While the number of studies are limited, the proportion of patients with impulse-control disorder in Parkinson patients treated with an add-on agonist were 32% for pramipexole, 25% for ropinirole, 16% for pergolide, 22% for rotigotine, 10% for apomorphine, and 6.8% for bromocriptine. Clinically, temporary replacement of pramipexole by bromocriptine may provide relief or reversal of the impulsive behavior associated with selective D3 stimulation by either pramipexole or ropinirole, while maintaining D2 stimulation needed for the anti-Parkinson action.

Background and Purpose Rotigotine acts as a dopamine receptor agonist with high affinity for the dopamine D2, D3, D4 and D5 receptors but with a low affinity for the dopamine D1 receptor. We have investigated this further in radioligand binding and functional studies and compared the profile of rotigotine with that of other drugs used in the treatment of Parkinson's disease (PD). Experimental Approach The binding of rotigotine to human dopamine D1, D2, D3, D4 and D5 receptors was determined in radioligand binding studies using [3H]rotigotine and compared with that of standard antagonist radioligands. Functional interactions of rotigotine with human dopamine receptors was also determined. Key Results [3H]rotigotine can be used as an agonist radioligand to label all dopamine receptor subtypes and this can be important to derive agonist affinity estimates. Rotigotine maintains this high affinity in functional studies at all dopamine receptors especially D1, D2 and D3 receptors and, to a lesser extent, D4 and D5 receptors. Rotigotine, like apomorphine but unlike ropinirole and pramipexole, was a potent agonist at all dopamine receptors. Conclusions and Implications Rotigotine is a high-potency agonist at human dopamine D1, D2 and D3 receptors with a lower potency at D4 and D5 receptors. These studies differentiate rotigotine from conventional dopamine D2 agonists, used in the treatment of PD, such as ropinirole and pramipexole which lack activity at the D1 and D5 receptors, but resembles that of apomorphine which has greater efficacy in PD than other dopamine agonists but has suboptimal pharmacokinetic properties.

Patients with Parkinson’s disease (PD) may experience impulse control disorders (ICDs) when on dopamine agonist therapy for their motor symptoms. In the last few years, there has been a rapid growth of interest for the recognition of these aberrant behaviors and their neurobiological correlates. Recent advances in neuroimaging are helping to identify the neuroanatomical networks responsible for these ICDs, and together with psychopharmacological assessments are providing new insights into the brain status of impulsive behavior. The genetic associations that may be unique to ICDs in PD are also being identified. Complementing human studies, electrophysiological and biochemical studies in animal models are providing insights into neuropathological mechanisms associated with these disorders. New animal models of ICDs in PD patients are being implemented that should provide critical means to identify efficacious therapies for PD-related motor deficits while avoiding ICD side effects. Here, we provide an overview of these recent advances, with a particular emphasis on the neurobiological correlates reported in animal models and patients along with their genetic underpinnings.

Background We previously reported on a cohort of dystonic tremor and patients with scans without evidence of dopaminergic deficit (SWEDDs). We aim to report the long-term clinical and imaging follow-up of these patients. Patients and Methods Patients with at least 5-year follow-up were included. These patients had an asymmetric arm tremor, a previous diagnosis of Parkinson's disease (PD), and a subsequent normal DaTscan. The imaging and clinical follow-up was done on the clinical basis. Results Sixteen patients were included. The mean gap between the first and subsequent scans was 5.4 years. Two patients (12.5%) had reduced nigrostriatal uptake on follow-up DaTscan, whereas 14 continued to have normal dopaminergic imaging. Conclusion This is the longest follow up of patients with asymmetric rest tremor and normal DaT scans (SWEDDs) reported to date. We show here that only a minority of them show reduced striatonigral uptake over long term follow up.

This phase I, open-label, single-dose study evaluated the pharmacokinetics, safety, and tolerability of renally excreted drug dexpramipexole in subjects with normal and impaired renal function, i.e. mild, moderate, severe renal impairment, or end-stage renal disease (ESRD) requiring hemodialysis when matched by age and sex. Dexpramipexole area under the curves (AUCs), but not Cmax , were significantly increased with the severity of renal impairment after a single dose administration. The geometric mean ratio of dose-normalized AUC(0-72) was 1.4, 1.7, 2.7, and 4.5, respectively, in mild, moderate, severe renal impairment, and ESRD subjects when compared to healthy subjects. There was a strong association between renal function (eGFR) and dexpramipexole CLr. The slope (90% confidence interval(CI)) of eGFR and renal clearance (CLr) in the regression model was 3.1 (2.4, 3.7). Dexpramipexole elimination in ESRD subjects during both dialysis and non-dialysis (i.e., interval between dialysis) was insignificant. Single 75 mg and 150 mg doses of dexpramipexole were well tolerated, and the safety profile was comparable across renal function groups. Extensive drug accumulation may occur with repeated dosing in patients with significant renal impairment. It is recommended that dexpramipexole not to be given to patients with severe renal impairment or in those with ESRD.

Dopamine agonists (DA) are often used as first-line monotherapy for the symptomatic control of Parkinson's disease (PD). However, DA monotherapy typically becomes inadequate within a few years, at which time the DA dosage must be increased or other antiparkinsonian medications added. Adding a monoamine oxidase-B (MAO-B) inhibitor to DA monotherapy might improve symptomatic control while maintaining good safety and tolerability. We conducted an 18-week, randomized, double-blind, placebo-controlled trial of rasagiline 1 mg/d as an add-on to DA therapy (ropinirole ≥ 6 mg/d or pramipexole ≥ 1.0 mg/d) in early PD patients whose conditions were not adequately controlled on their current treatment regimen. The primary efficacy variable was the change in total Unified Parkinson Disease Rating Scale (UPDRS) score (sum of parts I, II, and III) from baseline to week 18, comparing rasagiline and placebo groups. The modified intent-to-treat (ITT) population included 321 subjects whose mean ± SD age was 62.6 ± 9.7, and duration of PD was 2.1 ± 2.1 years. Results demonstrated a significantly greater improvement in total UPDRS scores from baseline to week 18 in the rasagiline group compared with the placebo group (least squares [LS] mean difference ± SE, −2.4 ± 0.95; 95% confidence interval [CI], −4.3, −0.5; P = 0.012). Mean improvement (LS mean ± SE) was −3.6 ± 0.68 in the rasagiline group and −1.2 ± 0.68 in the placebo group. Rasagiline was well tolerated, and the most common adverse events (AEs; rasagiline vs. placebo) were dizziness (7.4% vs. 6.1%), somnolence (6.8% vs. 6.7%), and headache (6.2% vs. 4.3%). Rasagiline 1 mg/d provided statistically significant improvement when added to dopamine agonist therapy and was well tolerated. © 2014 International Parkinson and Movement Disorder Society

Background and purpose To assess the long-term safety and efficacy of pramipexole as a once-daily (q.d.) extended-release oral formulation in early or advanced Parkinson's disease (PD). Methods In two double-blind (DB) studies of early PD and one of advanced PD, active-treatment arms received pramipexole immediate release (IR) or extended release (ER), with exposure lasting up to 33 weeks. In open-label (OL) extensions that followed immediately, subjects took ER q.d. for up to 80 weeks, with dosage adjustment permitted (range 0.375–4.5 mg q.d.). Results Of 590 subjects completing an early-PD DB study, 511 entered the early-PD OL extension; 408 completed it. Reported adverse events (AEs) with incidence ≥10.0% were somnolence (15.1%), peripheral edema (11.7%) and back pain (10.6%). Of 465 subjects completing the advanced-PD DB study, 391 entered the advanced-PD OL extension; 329 completed it. Reported AEs with incidence ≥10.0% were dyskinesia (27.4%) and somnolence (13.6%). Impulse control disorders were identified by semi-structured interview in 13 subjects (1.4% of 902). In exploratory analyses, adjusted mean Unified Parkinson's Disease Rating Scale (UPDRS) Parts II + III scores (excluding ex-placebo recipients) remained substantially improved from DB baseline scores prior to pramipexole introduction, at −6.6 and −6.3 points amongst ex-DB-ER and ex-DB-IR recipients after 113 weeks of pramipexole (33 DB plus 80 OL) in early PD, and −11.5 and −9.1 after up to 113 weeks (up to 33 DB plus 80 OL) in advanced PD. Conclusions These results support the long-term safety and efficacy of pramipexole ER in early and advanced PD. AEs were typical for dopaminergic medications, and UPDRS scores suggested sustained symptomatic benefit.

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Background and purpose It is not clear which is preferred between iron supplement and a dopamine agonist in the treatment of restless legs syndrome (RLS) with iron deficiency. The efficacies of oral iron supplementation and pramipexole for treatment of RLS with low-normal serum ferritin (15–50 ng/ml) were compared. Methods Thirty RLS patients who took either oral iron or pramipexole for 12 weeks and were followed at 2, 4, 8 and 12 weeks after treatment commencement were enrolled. Severities of RLS symptoms were assessed using the international RLS study group rating scale for severity (IRLS) at every visit. Treatment response was defined as a decrease in IRLS score of at least 50% from baseline. Results The 30 subjects were assigned equally to an iron or pramipexole group. At baseline, IRLS scores and serum ferritin levels were similar between these two groups. After 12 weeks, IRLS scores were lower than those at baseline in both groups (iron −9.1 ± 7.07, P

r r Abstract: The control of impulse behavior is a multidimensional concept subdivided into separate sub- components, which are thought to represent different underlying mechanisms due to either disinhibitory processes or poor decision-making. In patients with Parkinson's disease (PD), dopamine-agonist (DA) therapy has been associated with increased impulsive behavior. However, the relationship among these different components in the disease and the role of DA is not well understood. In this imaging study, we investigated in PD patients the effects of DA medication on patterns of brain activation during tasks test- ing impulsive choices and actions. Following overnight withdrawal of antiparkinsonian medication, PD patients were studied with a H2 (15) O PET before and after administration of DA (1 mg of pramipexole), while they were performing the delay discounting task (DDT) and the GoNoGo Task (GNG). We observed that pramipexole augmented impulsivity during DDT, depending on reward magnitude and activated the medial prefrontal cortex and posterior cingulate cortex and deactivated ventral striatum. In contrast, the effect of pramipexole during the GNG task was not significant on behavioral performance and involved different areas (i.e., lateral prefrontal cortex). A voxel-based correlation analysis revealed a significant negative correlation between the discounting value (k) and the activation of medial prefrontal cortex and posterior cingulate suggesting that more impulsive patients had less activation in those corti- cal areas. Here we report how these different subcomponents of inhibition/impulsivity are differentially sensitive to DA treatment with pramipexole influencing mainly the neural network underlying impulsive choices but not impulsive action. Hum Brain Mapp 35:2499-2506, 2014. V C 2013 Wiley Periodicals, Inc.

Aim This study was conducted to verify the reliability, validity, and responsiveness of the Japanese version of the International Restless Legs Syndrome Study Group Rating Scale for restless legs syndrome (J-IRLS) as a sub-study of a clinical trial of pramipexole against restless legs syndrome. Methods After evaluating the test–retest reliability, concurrent validity and construct validity were analyzed. The responsiveness of J-IRLS was confirmed by evaluating the correlations between the changes in J-IRLS total score after treatment, Clinical Global Impression Improvement Scale (CGI-I), and Patient Global Impression. Results Test–retest reliability of J-IRLS was good (intra-class correlation coefficient, 0.877; 95% confidence interval, 0.802–0.925). The correlation coefficient of J-IRLS total score and CGI-S score for the first and second visit was 0.804 and 0.796, respectively (both P

The aggregation of β-amyloid protein (Aβ) and α-synuclein (αS) are hypothesized to be the key pathogenic event in Alzheimer's disease (AD) and Lewy body diseases (LBD), with oligomeric assemblies thought to be the most neurotoxic. Inhibitors of oligomer formation, therefore, could be valuable therapeutics for patients with AD and LBD. Here, we examined the effects of antiparkinsonian agents (dopamine, levodopa, trihexyphenidyl, selegiline, zonisamide, bromocriptine, peroxide, ropinirole, pramipexole, and entacapone) on the in vitro oligomer formation of Aβ40, Aβ42, and αS using a method of photo-induced cross-linking of unmodified proteins (PICUP), electron microscopy, and atomic force microscopy. The antiparkinsonian agents except for trihexyphenidyl inhibited both Aβ and αS oligomer formations, and, among them, dopamine, levodopa, pramipexole, and entacapone had the stronger in vitro activity. Circular dichroism and thioflavin T(S) assays showed that secondary structures of Aβ and αS assemblies inhibited by antiparkinsonian agents were statistical coil state and that their seeding activities had disappeared. The antiparkinsonian agents could be potential therapeutic agents to prevent or delay AD and LBD progression.

A selective deficit in the recollection of episodic details is frequently reported in Parkinson's disease (PD). Previous explanations implicate dopamine dysregulation in prefrontal structures on which strategic memory processes rely. However, neuroimaging advancements suggest dopaminergic dysregulation of hippocampally dependent memory processes. Accordingly, dopamine agonists, which target D3 receptors in the hippocampus, may impair hippocampal functioning, causing a more pronounced recollection decline. Recognition memory (RM), familiarity, and recollection were examined in 21 patients with mild-to-moderate PD (Hoehn and Yahr mean: 2.67). Patients were subdivided into two subgroups according to dopamine agonist (pramipexole [PPX] or ropinirole [RPR]), and completed matched versions of an RM test in a medicated and unmedicated condition (termed ON and OFF, respectively). Ten demographically matched healthy volunteers (HVs) also completed both RM tasks in two separate sessions. The PD group (PPX and RPR subgroups combined) showed impairments in RM and recollection, but spared familiarity. When subdivided by dopamine agonist, the PPX subgroup's ON-medication recollection performance was significantly lower than that of both the HVs and RPR subgroup. There was no evidence of decline in OFF-medication recollection or familiarity in either the PPX or RPR subgroups. Recollection in both PD subgroups correlated positively with a composite measure of recall, but not prefrontally dependent measures of cognitive control. These findings suggest that mild-to-moderate PD patients may show relatively preserved recollection and familiarity, but that recollection is selectively disrupted by PPX, but not RPR and that this effect may depend on disrupted hippocampal function rather than impaired pre-frontally dependent executive functions.

Evaluating the effects of presession drug administration on intertemporal choice in nonhumans is a useful approach for identifying compounds that promote impulsive behavior in clinical populations, such as those prescribed the dopamine agonist pramipexole (PPX). Based on the results of previous studies, it is unclear whether PPX increases rats' impulsive choice or attenuates aspects of stimulus control. The present study was designed to experimentally isolate behavioral processes fundamental to intertemporal choice and challenge them pharmacologically with PPX administration. In Experiment 1, the hypothesis that PPX increases impulsive choice as a result of enhanced sensitivity to reinforcer delays was tested and disconfirmed. That is, acute PPX diminished delay sensitivity in a manner consistent with disruption of stimulus control whereas repeated PPX had no effect on delay sensitivity. Experiments 2 and 3 elaborated upon this finding by examining the effects of repeated PPX on rats' discrimination of response-reinforcer contingencies and reinforcer amounts, respectively. Accuracy of both discriminations was reduced by PPX. Collectively these results provide no support for past studies that have suggested PPX increases impulsive choice. Instead, PPX impairs stimulus control over choice behavior. The behavioral approach adopted herein could be profitably integrated with genetic and other biobehavioral models to advance our understanding of impulsive behavior associated with drug administration.

Gγ7 is enriched in striatum and forms a heterotrimeric complex with Gαolf /Gβ, which is coupled to D1 receptor (D1R). Here, we attempted to characterize the pathophysiological, neurochemical, and pharmacological features of mice deficient of Gγ7 gene. Gγ7 knockout mice exhibited age-dependent deficiency in rotarod behavior and increased dystonia-like clasping reflex without loss of striatal neurons. The neurochemical basis for the motor manifestations using immunoblot analysis revealed increased levels of D1R, ChAT and NMDA receptor subunits (NR1 and NR2B) concurrent with decreased levels of D2R and Gαolf , possibly because of the secondary changes of decreased Gαolf /Gγ7-mediated D1R transmission. These behavioral and neurochemical changes are closely related to those observed in Huntington's disease (HD) human subjects and HD model mice. Taking advantage of the finding of D2R down-regulation in Gγ7 knockout mice and the dopamine-mediated synergistic relationship in the control of locomotion between D2R-striatopallidal and D1R-stritonigral neurons, we hypothesized that D2-agonist pramipexole would reverse behavioral dyskinesia caused by defective D1R/Gαolf signaling. Indeed, the rotarod deficiency and clasping reflex were reversed by pramipexole treatment under chronic administration. These findings suggest that Gγ7 knockout mice could be a new type of movement disorders, including HD and useful for the evaluation of therapeutic candidates.

Adenosine A2A receptor antagonists reduce or prevent the development of dyskinesia in animal models of levodopa-induced dyskinesia.We examined the association between self-reported intake of the A2A receptor antagonist caffeine and time to dyskinesia in the Comparison of the Agonist Pramipexole with Levodopa on Motor Complications of Parkinson's Disease (CALM-PD) and CALM Cohort extension studies, using a Cox proportional hazards model adjusting for age, baseline Parkinson's severity, site, and initial treatment with pramipexole or levodopa.For subjects who consumed12 ounces of coffee/day, the adjusted hazard ratio for the development of dyskinesia was 0.61 (95% CI, 0.37-1.01) compared with subjects who consumed4 ounces/day. For subjects who consumed between 4 and 12 ounces/day, the adjusted hazard ratio was 0.73 (95% CI, 0.46-1.15; test for trend, P = .05).These results support the possibility that caffeine may reduce the likelihood of developing dyskinesia.

Sienaert P, Lambrichts L, Dols A, De Fruyt J. Evidence-based treatment strategies for treatment-resistant bipolar depression: a systematic review. Bipolar Disord 2012: 00: 000–000. © 2012 John Wiley & Sons A/S.Published by Blackwell Publishing Ltd. Objectives: Treatment resistance in bipolar depression is a common clinical problem that constitutes a major challenge for the treating clinician as there is a paucity of treatment options. The objective of this paper was to review the evidence for treatment options in treatment-resistant bipolar depression, as found in randomized controlled trials and with special attention to the definition and assessment of treatment resistance. Methods: A Medline search (from database inception to May 2012) was performed using the search terms treatment resistance or treatment refractory, and bipolar depression or bipolar disorder, supplemented with 43 separate searches using the various pharmacologic agents or technical interventions as search terms. Results: Only seven studies met our inclusion criteria. These studies examined the effects of ketamine (n = 1), (ar)modafinil (n = 2), pramipexole (n = 1), lamotrigine (n = 1), inositol (n = 1), risperidone (n = 1), and electroconvulsive therapy (ECT) (n = 2). Conclusions: The available level I evidence for treatment strategies in resistant bipolar depression is extremely scarce, and although the response rates reported are reassuring, most of the strategies remain experimental. There is an urgent need for further study in homogeneous patient samples using a clear concept of treatment resistance.

The purpose of this study was to characterize the nature of the relation between periodic leg movements during sleep (PLMS) and cortical arousals to contribute to the debate on the clinical significance and treatment of PLMS.A prospective, placebo-controlled, single-blind, parallel group study was carried out including 46 drug-naive patients with idiopathic restless legs syndrome (RLS). Each patient underwent 2 consecutive full-night polysomnographic studies. The first night was the baseline night. Prior to the second night, 1 group received a single oral dose of 0.25mg pramipexole, whereas a second group received a single oral dose of 0.5mg clonazepam, and the remaining patients received placebo. Sleep stages, cyclic alternating pattern (CAP), and leg movement activity were scored following standard criteria; symptoms of RLS were also assessed.Pramipexole suppressed PLMS without affecting electroencephalographic (EEG) instability (CAP) and arousals (corresponding to CAP A3 and, partially, A2 subtypes), whereas clonazepam did the opposite, reducing non-rapid eye movement sleep EEG instability without effects on PLMS. Both drugs were effective on sensory RLS symptoms.This study demonstrates that a selective pharmacological approach can disconnect PLMS from arousal events, suggesting an indirect relation between each other. These results might weaken the hypothesis of a direct pathological role of PLMS in sleep disruption and can be important for the discussion on the existence of a distinct entity called periodic limb movements disorder. Moreover, the study opens the doors to the possibility of a joint treatment for RLS targeting sensory and motor symptoms, as well as sleep instability.

Background and purpose: In chronic diseases including Parkinson’s disease (PD), complex pharmacotherapy dosing schedules are reported to reduce adherence, perhaps leading to less-effective symptom control and, in PD, more erratic stimulation of dopamine receptors. However, blinded clinical-trial designs preclude direct comparisons of adherence to various schedules. Methods: In two double-blind (DB) studies of early PD and one of advanced PD, subjects received three-times-daily (t.i.d.) pramipexole or placebo. In open-label (OL) extensions, subjects took extended-release, once-daily (q.d.) pramipexole. At 24 or 32 OL weeks, q.d. versus t.i.d. dosing preference was surveyed by questionnaire. Results: Of 590 DB-trial completers with early PD, 511 entered the OL extension. Of 374 survey respondents, 94.4% preferred q.d. dosing (72.2% of them found it ‘very much more convenient’ and 27.8%‘more convenient’), 2.7% preferred t.i.d., and 2.9% chose ‘no difference’. Of 465 DB-trial completers with advanced PD, 391 entered its OL extension. Of 334 survey respondents, 88.9% preferred q.d. dosing (59.9% of them found it ‘very much more convenient’ and 40.1%‘more convenient’), 5.7% preferred t.i.d., and 5.4% chose ‘no difference’. Results excluding DB-placebo recipients were highly similar. Conclusions: In this first direct comparison of patient preference for q.d. versus t.i.d. dopamine-agonist dosing, patients with early or advanced PD had a strong preference for q.d. rather than t.i.d. pramipexole. The high proportion of advanced-PD patients declaring this preference indicates that it does not depend on whether a patient is taking concomitant PD medications dosed more frequently than q.d.

Background: Dopamine agonists could theoretically normalize the suspected central dopamine hypersensitivity in Tourette's syndrome. Methods: There was a multicenter randomized, placebo-controlled, double-blind clinical trial of pramipexole given for 6 weeks in 63 children and adolescents with Tourette's syndrome. Results: There were no significant differences in the adjusted mean change in the Total Tic Score of the Yale Global Tic Severity Scale for patients treated with pramipexole (−7.16) and placebo (−7.17). There were no significant treatment effects on change from baseline in the Global Severity score of the Yale Scale and parent- and investigator-scored Clinical Global Impression of Improvement. In patients with attention deficit hyperactivity disorder, there was improvement in DuPaul ADHD scale scores for patients receiving pramipexole compared with placebo. Conclusions: There was no evidence that pramipexole has efficacy in suppressing tics. Pramipexole may decrease symptoms of associated attention deficit hyperactivity disorder. © 2012 Movement Disorder Society

Restless leg syndrome (RLS) is a major healthcare burden with increasing prevalence. It has been demonstrated that periodic limb movements (PLM) can occur as an isolated phenomenon, but they are often associated with this syndrome and are the only symptom of this disorder that can be measured electro- physiologically. The aim of this study was to examine the sleep-wake behavior and the presence of limb move- ment in a rat model of RLS induced by lesioning the A11 dopaminergic nuclei with the neurotoxin 6-hydroxydopa- mine (6-OHDA). Rats were implanted with electrodes for electrocorticography and electromyography. Sleep recordings were monitored during light/dark periods last- ing 12 hours each and were evaluated on days 7, 15, and 28 after injection of the drug or phosphate-buffered saline (PBS). A control group that did not receive any injection was also included. Wakefulness percentages were generated for 4-hour segments of the dark period, yielding the following 3 bins: 7 PM to 11 PM ,1 1PM to 3 AM ,a nd 3PM to 7 PM. Additionally, slow wave sleep, par- adoxical sleep, wakefulness, and limb movements were evaluated over the entire 12 hours of the light/dark cycle. All A11-lesioned rats exhibited an increased percentage of wakefulness during the last block of the dark period, as would be expected for an animal model of this syn- drome. In addition, at all time points after lesioning, these animals presented increased frequencies of limb movement during both the light and the dark periods. These alterations were reversed by the acute administra- tion of the dopaminergic agonist pramipexole. This ani- mal model strengthens the notion that 6-OHDA-induced A11 lesions can be a valid animal model for RLS and PLM. V C 2011 Movement Disorder Society

Introduction A potential risk of heart failure was recently observed in randomized trials of the dopamine agonist pramipexole. The extent of the risk with this and other dopamine agonists is unknown. Methods We used the UK General Practice Research Database (GPRD) to identify all users of anti-parkinsonian drugs, 40–89 years of age, between 1997 and 2009. All incident heart failure cases were identified and classified as probable or possible on the basis of their treatment and mortality. Using a nested case–control approach, each case was matched with up to 10 controls selected among the cohort members. Incidence rate ratios (RR) of heart failure associated with the current use of dopamine agonists were estimated using conditional logistic regression, adjusted for covariates. Results The cohort included 26 814 users of anti-parkinsonian drugs, with 783 newly diagnosed with heart failure during follow-up (rate 8.7 per 1000 per year). The incidence rate of heart failure was increased with the current use of any dopamine agonist (RR = 1.58, 95% CI = 1.26–1.96), and particularly so for pramipexole (RR = 1.86, 95%CI = 1.21–2.85) and cabergoline (RR = 2.07, 95%CI = 1.39–3.07), compared with no use. The increase was not significant with ropinirole (RR = 1.23, 95%CI = 0.85–1.97) or pergolide (RR = 1.42, 95%CI = 0.95–2.12). Pramipexole was not associated with a significantly increased rate when compared with all other dopamine agonists collectively (RR = 1.28, 95%CI = 0.82–2.00). Discussion The use of dopamine agonists, especially pramipexole and cabergoline, is associated with an increased risk of heart failure. Copyright © 2011 John Wiley & Sons, Ltd.

Safinamide is an α-aminoamide with both dopaminergic and nondopaminergic mechanisms of action evaluated as an add-on to dopamine agonist (DA) therapy in early-stage PD. In this 24-week, double-blind study, patients with early PD receiving a stable dose of a single DA were randomized to once-daily safinamide 100 mg, safinamide 200 mg, or placebo. The primary efficacy variable was UPDRS part III (motor examination) total score. Analysis was hierarchical: 200 mg of safinamide versus placebo was tested first; the success of safinamide 100 mg versus placebo was contingent on this. Two hundred sixty-nine patients received safinamide 100 mg (n = 90), safinamide 200 mg (n = 89), or placebo (n = 90); 70, 81, and 81 patients, respectively, completed the study. Mean improvements from baseline to week 24 in UPDRS III total scores were -3.90 for safinamide 200 mg, -6.0 for safinamide 100 mg and -3.60 for placebo. The difference between safinamide 200 mg and placebo was not significant [point estimate: -0.4; 95% confidence interval (CI): -2.3-1.4; P = 0.6504]. Although the difference between 100 mg/day and placebo was significant (point estimate: -1.9; 95% CI: -3.7 to -0.1; P = 0.0419), these results are considered exploratory. No clinically meaningful differences from placebo were observed for any safety variables. This study did not demonstrate a significant improvement of the primary endpoint for safinamide 200 mg/day. Exploratory analysis of the primary endpoint for 100 mg/day demonstrated that the addition of safinamide to a stable dose of DA improves motor symptoms in early PD and warrants further investigation.

A rapid method for the enantioseparation of pramipexole and its R-enantiomer has been developed by capillary electrophoresis. The influence of chemical and instrumental parameters was investigated including the type and concentration of chiral selectors, buffer composition and pH, co-ions, applied voltage, capillary length and temperature. Optimal separation conditions were obtained using a 50 mM phosphate buffer (pH 2.8) containing 25 mM carboxymethyl-β-cyclodextrin on a fused-silica capillary. Online UV detection was performed at 262 nm. A voltage of 25 kV was applied, and the capillary temperature was kept at 25°C. Hydrodynamic injection was performed at 3.45 kPa for 5.0 s. The separation of enantiomers was achieved in6.5 min. The method was further validated in terms of stability of solutions, selectivity, linearity (both pramipexole and R-enantiomer, R(2)0.995), LOD and LOQ (0.91 and 2.94 μg/mL, respectively), repeatability (RSD1.5%) and accuracy (pramipexole, 100.4%; R-enantiomer, 100.5%). The proposed method was then applied to two kinds of pramipexole dihydrochloride monohydrate commercially available tablets, immediate release tablets (1.50 and 0.125 mg) and sustained release tablets (0.52 mg), to quantify the main component in the tablets. The amount of distomer could be quantified in bulk sample materials.