Objective The objective of this review was to update evidence-based medicine recommendations for treating motor symptoms of Parkinson's disease (PD). Background The Movement Disorder Society Evidence-Based Medicine Committee recommendations for treatments of PD were first published in 2002 and updated in 2011, and we continued the review to December 31, 2016. Methods Level I studies of interventions for motor symptoms were reviewed. Criteria for inclusion and quality scoring were as previously reported. Five clinical indications were considered, and conclusions regarding the implications for clinical practice are reported. Results A total of 143 new studies qualified. There are no clinically useful interventions to prevent/delay disease progression. For monotherapy of early PD, nonergot dopamine agonists, oral levodopa preparations, selegiline, and rasagiline are clinically useful. For adjunct therapy in early/stable PD, nonergot dopamine agonists, rasagiline, and zonisamide are clinically useful. For adjunct therapy in optimized PD for general or specific motor symptoms including gait, rivastigmine is possibly useful and physiotherapy is clinically useful; exercise-based movement strategy training and formalized patterned exercises are possibly useful. There are no new studies and no changes in the conclusions for the prevention/delay of motor complications. For treating motor fluctuations, most nonergot dopamine agonists, pergolide, levodopa ER, levodopa intestinal infusion, entacapone, opicapone, rasagiline, zonisamide, safinamide, and bilateral STN and GPi DBS are clinically useful. For dyskinesia, amantadine, clozapine, and bilateral STN DBS and GPi DBS are clinically useful. Conclusions The options for treating PD symptoms continues to expand. These recommendations allow the treating physician to determine which intervention to recommend to an individual patient. © 2018 International Parkinson and Movement Disorder Society.

International Parkinson and movement disorder society evidence‐based medicine review: Update on treatments for the motor symptoms of Parkinson's disease

Pathophysiology of L-dopa-induced motor and non-motor complications in Parkinson's disease.

Many naturally occurring substances, traditionally used in popular medicines around the world, contain the coumarin moiety. Coumarin represents a privileged scaffold for medicinal chemists, because of its peculiar physicochemical features, and the versatile and easy synthetic transformation into a large variety of functionalized coumarins. As a consequence, a huge number of coumarin derivatives have been designed, synthesized, and tested to address many pharmacological targets in a selective way, e.g., selective enzyme inhibitors, and more recently, a number of selected targets (multitarget ligands) involved in multifactorial diseases, such as Alzheimer’s and Parkinson’s diseases. In this review an overview of the most recent synthetic pathways leading to mono- and polyfunctionalized coumarins will be presented, along with the main biological pathways of their biosynthesis and metabolic transformations. The many existing and recent reviews in the field prompted us to make some drastic selections, and therefore, the review is focused on monoamine oxidase, cholinesterase, and aromatase inhibitors, and on multitarget coumarins acting on selected targets of neurodegenerative diseases.

Coumarin: A Natural, Privileged and Versatile Scaffold for Bioactive Compounds

Inhibitors of MAO-A and MAO-B are in clinical use for the treatment of psychiatric and neurological disorders respectively. Elucidation of the molecular structure of the active sites of the enzymes has enabled a precise determination of the way in which substrates and inhibitor molecules are metabolized, or inhibit metabolism of substrates, respectively. Despite the knowledge of the strong antidepressant efficacy of irreversible MAO inhibitors, their clinical use has been limited by their side effect of potentiation of the cardiovascular effects of dietary amines (“cheese effect”). A number of reversible MAO-A inhibitors which are devoid of cheese effect have been described in the literature, but only one, moclobemide, is currently in clinical use. The irreversible inhibitors of MAO-B, selegiline and rasagiline, are used clinically in treatment of Parkinson’s disease, and a recently introduced reversible MAO-B inhibitor, safinamide, has also been found efficacious. Modification of the pharmacokinetic characteristics of selegiline by transdermal administration has led to the development of a new drug form for treatment of depression. The clinical potential of MAO inhibitors together with detailed knowledge of the enzyme’s binding site structure should lead to future developments with these drugs.

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Inhibitors of MAO-A and MAO-B in Psychiatry and Neurology

IMPORTANCE: 
Although levodopa remains the most effective oral pharmacotherapy for Parkinson disease (PD), its use is often limited by wearing off effect and dyskinesias. Management of such complications continues to be a significant challenge.

OBJECTIVE: 
To investigate the efficacy and safety of safinamide (an oral aminoamide derivative with dopaminergic and nondopaminergic actions) in levodopa-treated patients with motor fluctuations.

DESIGN, SETTING, AND PARTICIPANTS: 
From March 5, 2009, through February 23, 2012, patients from academic PD care centers were randomized (1:1 ratio) to receive double-blind adjunctive safinamide or placebo for 24 weeks. All patients had idiopathic PD with “off” time (time when medication effect has worn off and parkinsonian features, including bradykinesia and rigidity, return) of greater than 1.5 hours per day (excluding morning akinesia). Their pharmacotherapy included oral levodopa plus benserazide or carbidopa in a regimen that had been stable for 4 weeks or longer. During screening, each patient’s regimen was optimized to minimize motor fluctuations. Study eligibility required that after 4 weeks of optimized treatment, the patients still have more than 1.5 hours per day of off time. Adverse events caused the premature study discontinuation of 12 individuals (4.4%) in the safinamide group and 10 individuals (3.6%) in the placebo group.


INTERVENTIONS: 
Patients took safinamide or placebo as 1 tablet daily with breakfast. If no tolerability issues arose by day 14, the starting dose, 50 mg, was increased to 100 mg.

MAIN OUTCOMES AND MEASURES: 
The prespecified primary outcome was each treatment group’s mean change from baseline to week 24 (or last “on” treatment value) in daily “on” time (relief of parkinsonian motor features) without troublesome dyskinesia, as assessed from diary data.

RESULTS: 
At 119 centers, 549 patients were randomized (mean [SD] age, 61.9 [9.0] years; 334 male [60.8%] and 371 white [67.6%]): 274 to safinamide and 275 to placebo. Among them, 245 (89.4%) receiving safinamide and 241 (87.6%) receiving placebo completed the study. Mean (SD) change in daily on time without troublesome dyskinesia was +1.42 (2.80) hours for safinamide, from a baseline of 9.30 (2.41) hours, vs +0.57 (2.47) hours for placebo, from a baseline of 9.06 (2.50) hours (least-squares mean difference, 0.96 hour; 95% CI, 0.56-1.37 hours; P < .001, analysis of covariance). The most frequently reported adverse event was dyskinesia (in 40 [14.6%] vs 15 [5.5%] and as a severe event in 5 [1.8%] vs 1 [0.4%]).

CONCLUSIONS AND RELEVANCE: 
The outcomes of this trial support safinamide as an effective adjunct to levodopa in patients with PD and motor fluctuations to improve on time without troublesome dyskinesia and reduce wearing off.

/pdf/assessment-of-safety-and-efficacy-of-safinamide-as-a-4nntd6g959.pdf

Assessment of Safety and Efficacy of Safinamide as a Levodopa Adjunct in Patients With Parkinson Disease and Motor Fluctuations: A Randomized Clinical Trial.

In a 6-month double-blind, placebo-controlled study of Parkinson's disease patients with motor fluctuations, safinamide 50 and 100 mg/d significantly increased ON-time without increasing dyskinesia. Further long-term safinamide use in these patients was evaluated over an additional 18 months. Patients continued on their randomized placebo, 50, or 100 mg/d safinamide. The primary endpoint was change in Dyskinesia Rating Scale total score during ON-time over 24 months. Other efficacy endpoints included change in ON-time without troublesome dyskinesia, changes in individual diary categories, depressive symptoms, and quality of life measures. Change in Dyskinesia Rating Scale was not significantly different in safinamide versus placebo groups, despite decreased mean total Dyskinesia Rating Scale with safinamide compared with an almost unchanged score in placebo. Ad hoc subgroup analysis of moderate to severe dyskinetic patients at baseline (36% of patients) showed a decrease with safinamide 100 mg/d compared with placebo (P = 0.0317). Improvements in motor function, activities of daily living, depressive symptoms, clinical status, and quality of life at 6 months remained significant at 24 months. Adverse events and discontinuation rates were similar with safinamide and placebo. This 2-year, controlled study of add-on safinamide in mid-to-late Parkinson's disease with motor fluctuations, although not demonstrating an overall difference in dyskinesias between patients and controls, showed improvement in dyskinesia in patients at least moderately dyskinetic at baseline. The study additionally demonstrated significant clinical benefits in ON-time (without troublesome dyskinesia), OFF-time, activities of daily living, motor symptoms, quality of life, and symptoms of depression.

https://www.onlinelibrary.wiley.com/doi/pdf/10.1002/mds.25961

Dana Chirilineau

Papers

Two-Year, randomized, controlled study of safinamide as add-on to levodopa in mid to late Parkinson's disease