Safinamide as Add-On Therapy to Levodopa in Mid- to Late-Stage Parkinson's Disease Fluctuating Patients: Post hoc Analyses of Studies 016 and SETTLE

Safinamide as adjunctive therapy to levodopa monotherapy for patients with Parkinson's disease with wearing-off: The Japanese observational J-SILVER study

BACKGROUND

Safinamide is an effective adjunctive therapy for wearing-off in Parkinson's disease (PD); however, evidence is lacking in older patients and those in the early stages of wearing-off. This study evaluated the efficacy and safety of safinamide as adjunctive therapy in patients with PD treated with levodopa monotherapy in clinical practice.

METHODS

This multicentre, open-label observational study was conducted at five sites in Japan. Patients diagnosed with PD and wearing-off initiated safinamide as adjunctive therapy with levodopa monotherapy. Efficacy endpoints were mean changes in Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part I, III, and IV scores; daily ON-time without dyskinesia using 24-h patient symptom diaries; and 39-item Parkinson's Disease Questionnaire (PDQ-39) scores at 18 weeks of treatment.

RESULTS

In total, 24 patients initiated safinamide (66.7% were aged ≥75 years); the mean duration of wearing-off was 1.2 years. MDS-UPDRS Part III total score, Part IV total score, and PDQ-39 summary index decreased significantly from baseline (mean change -7.0 [p = 0.012], -2.4 [p = 0.007] and - 5.3 [p = 0.012], respectively). There was a non-statistically significant increase of 1.55 h in mean daily ON-time without dyskinesia. Numerical Rating Scale total score for pain (p = 0.015), and scores for OFF-period pain (p = 0.012) and nocturnal pain (p = 0.021) subdomains were significantly improved in the subgroup with pain. Most reported adverse events were classified as mild.

CONCLUSION

Safinamide improved motor and non-motor symptoms and quality of life-related measures in older patients with PD in the early stages of wearing-off without new safety concerns.

STUDY REGISTRATION

University Hospital Medical Information Network in Japan; study ID: UMIN000044341.

A neoteric annotation on the advances in combination therapy for Parkinson's disease: nanocarrier-based combination approach and future anticipation. Part I: exploring theoretical insights and pharmacological advances

INTRODUCTION

Parkinson's disease (PD) is a neurological condition defined by a substantial reduction in dopamine-containing cells in the substantia nigra. Levodopa (L-Dopa) is considered the gold standard in treatment. Recent research has clearly shown that resistance to existing therapies can develop. Moreover, the involvement of multiple pathways in the nigrostriatal dopaminergic neuronal loss suggests that modifying the treatment strategy could effectively reduce this degeneration.

AREAS COVERED

This review summarizes the key concerns with treating PD patients and the combinations, aimed at effectively managing PD. Part I focuses on the clinical diagnosis at every stage of the disease as well as the pharmacological treatment strategies that are applied throughout its course. It methodically elucidates the potency of multifactorial interventions in attenuating the disease trajectory, substantiating the rationale for co-administration of dual or multiple therapeutic agents. Significant emphasis is laid on evidence-based pharmacological combinations for PD management.

EXPERT OPINION

By utilizing multiple drugs in a combination fashion, this approach can leverage the additive or synergistic effects of these agents, amplify the spectrum of treatment, and curtail the risk of side effects by reducing the dose of each drug, demonstrating significantly greater efficacy.

The Effects of Safinamide in Chinese and Non-Chinese Patients with Parkinson's Disease

INTRODUCTION

Ethnicity differences are an important determinant in the clinical manifestation of Parkinson's disease (PD), but they are not yet widely recognized, particularly regarding the response to dopaminergic medications. The aim of this paper is to analyze the efficacy and safety of safinamide in Chinese patients with PD in the pivotal studies SETTLE and XINDI compared to the non-Chinese population of the SETTLE trial.

METHODS

SETTLE (NCT00627640) and XINDI (NCT03881371) were phase III, randomized, double-blind, placebo-controlled, multicenter trials. Patients received safinamide or placebo as add-on to levodopa. The primary efficacy endpoint was the change in the mean total daily OFF time. Secondary efficacy endpoints included total daily ON time, ON time with no/non-troublesome dyskinesia, Unified Parkinson's Disease Rating Scale, and Parkinson's Disease Questionnaire-39 items. Safety was evaluated through the frequency of adverse events. Data from 440 non-Chinese and 109 Chinese patients in the SETTLE study, and 305 Chinese patients in the XINDI trial were considered for this post hoc analysis.

RESULTS

Significant positive results were seen in favor of safinamide in all populations for the primary and secondary endpoints, with no differences in terms of magnitude. No "treatment by ethnicity" interaction was detected for any parameters, confirming the homogeneity of treatment effects between different populations. The safety and tolerability of safinamide in Chinese patients were similar to those in the other ethnic groups, without unexpected adverse reactions.

CONCLUSIONS

Safinamide was shown to improve PD symptoms and quality of life in different ethnic populations, without any treatment by race interaction. Further studies are warranted to investigate potential differences in a real-life situation.

TRIAL REGISTRATION NUMBER

SETTLE (NCT00627640) and XINDI (NCT03881371).

Real-world use of Safinamide in motor fluctuating Parkinson's disease patients in Italy

INTRODUCTION

Safinamide is a recent antiparkinsonian drug that modulates both dopaminergic and glutamatergic systems with positive effects on motor and nonmotor symptoms of Parkinson's disease (PD). Here, we aimed to describe the efficacy and safety of safinamide in the Italian PD patients in real-life conditions.

METHODS

We performed a sub-analysis of the Italian cohort of the SYNAPSES study, a multi-country, multi-center, retrospective-prospective cohort observational study, designed to investigate the use of safinamide in routine clinical practice. Patients received for the first time a treatment with safinamide and were followed up for 12 months. The analysis was conducted on the overall population and in subgroups of interest: i) patients > 75 years, ii) patients with relevant comorbidities and iii) patients affected by psychiatric symptoms.

RESULTS

Italy enrolled 616/1610 patients in 52 centers, accounting for 38% of the entire SYNAPSES cohort. Of the patients enrolled, 86.0% were evaluable at 12 months, with 23.3% being > 75 years, 42.4% with psychiatric conditions and 67.7% with relevant comorbidities. Safinamide was effective on motor symptoms and fluctuations as measured through the Unified PD rating scale III and IV scores, and on the total score, without safety issues in none of the subgroups considered.

CONCLUSION

The SYNAPSES data related to Italian patients confirms the good safety profile of safinamide even in special groups of patients. Motor fluctuations and motor impairment improved at the follow-up suggesting the significant role of safinamide in managing motor symptoms in PD patients.

Type-B monoamine oxidase inhibitors in neurological diseases: clinical applications based on preclinical findings

Type-B monoamine oxidase inhibitors, encompassing selegiline, rasagiline, and safinamide, are available to treat Parkinson's disease. These drugs ameliorate motor symptoms and improve motor fluctuation in the advanced stages of the disease. There is also evidence supporting the benefit of type-B monoamine oxidase inhibitors on non-motor symptoms of Parkinson's disease, such as mood deflection, cognitive impairment, sleep disturbances, and fatigue. Preclinical studies indicate that type-B monoamine oxidase inhibitors hold a strong neuroprotective potential in Parkinson's disease and other neurodegenerative diseases for reducing oxidative stress and stimulating the production and release of neurotrophic factors, particularly glial cell line-derived neurotrophic factor, which support dopaminergic neurons. Besides, safinamide may interfere with neurodegenerative mechanisms, counteracting excessive glutamate overdrive in basal ganglia motor circuit and reducing death from excitotoxicity. Due to the dual mechanism of action, the new generation of type-B monoamine oxidase inhibitors, including safinamide, is gaining interest in other neurological pathologies, and many supporting preclinical studies are now available. The potential fields of application concern epilepsy, Duchenne muscular dystrophy, multiple sclerosis, and above all, ischemic brain injury. The purpose of this review is to investigate the preclinical and clinical pharmacology of selegiline, rasagiline, and safinamide in Parkinson's disease and beyond, focusing on possible future therapeutic applications.

Real world data of a German Parkinson's disease population: effectiveness and safety of safinamide in routine clinical practice

BACKGROUND

Parkinson's Disease (PD) is a common progressive neurodegenerative disorder that leads to an imbalance of various neurotransmitters and affects cognitive, motor and non-motor function. Safinamide inhibits monoamine oxidase B in a highly selective and reversible manner and beyond that has anti-glutamatergic properties, with positive effects on motor and non-motor symptoms. The aim of the study was to obtain data about the effectiveness and tolerability of safinamide under routine clinical practice conditions in unselected patients with Parkinson's disease (PD).

METHODS

A post-hoc analysis of the German cohort of the European SYNAPSES study (a non-interventional cohort study). Patients were treated with safinamide as an add-on to levodopa and followed-up for 12 months. Analyses were done in the total cohort and in clinically relevant subgroups (patients older than 75 years; with relevant comorbidities; with psychiatric conditions).

RESULTS

181 PD patients were eligible for analysis. Motor symptoms included bradykinesia (76.8%), rigidity (77.3%), tremor (58.6%), and postural instability (27.1%). Non-motor symptoms were reported in 161 patients (89.0%), mainly psychiatric symptoms (43.1%), sleep disorders (35.9%), fatigue (30.9%), and pain (27.6%). 28.7% of patients were aged 75 years or older, 84.5% had relevant comorbidities, and 38.1% had psychiatric conditions. During treatment, the rate of motor complications decreased from 100.0% to 71.1%. UPDRS scores improved under safinamide, with a clinically important effect in 50% in the total score and 45% in the motor score. The positive effect on motor complications occurred already at the 4-month visit and was maintained over 12 months. At least one adverse event (AE)/adverse drug reaction (ADR) was reported by 62.4%/25.4% of patients, AEs were generally mild or moderate, and completely resolved. Only 5 (1.5%) AEs had a definite relationship to safinamide.

CONCLUSIONS

The benefit-risk profile of safinamide was favourable and consistent with the total cohort of the SYNAPSES study. In the subgroups, findings were congruent with the total population, which allows the clinical utilisation of safinamide also in more vulnerable patient groups.

Pharmacokinetic and Safety Study of Single and Multiple Oral Doses of Safinamide in Healthy Chinese Volunteers

This randomized, parallel-group study evaluated the plasma pharmacokinetic profile of safinamide in 24 healthy Chinese men and women, randomly assigned to receive 50 or 100 mg of safinamide as a single dose, followed, after a 7-day washout, by multiple doses once daily for 7 days. Plasma safinamide was determined up to 96 h after the first single dose (day 1) and the last multiple dose (day 14), and up to 24 h after the first multiple dose (day 8). Following single- and multiple-dose administration, peak concentrations were achieved at a median time of 1.5-2 h. Plasma exposure increased in a dose-proportional manner. After single dose, mean half-life was 23-24 h. Area under the concentration-time curve (AUC) from time zero extrapolated to infinity was only slightly higher than AUC from time zero to the last quantifiable concentration, corresponding for the 2 parameters, respectively, to 12,380 and 11,560 ng • h/mL for the 50 mg and to 22,030 and 20,790 ng • h/mL for the 100-mg dose. AUC in the dosing interval at steady state was 13,150 and 23,100 ng • h/mL for 50 and 100 mg of safinamide. Steady state was reached in 6 days, accumulation was approximately twofold, and the pharmacokinetics were time independent. The plasma safinamide pharmacokinetic profile observed in this study is in line with the published results in both Chinese and non-Asian populations.

Safety review of current pharmacotherapies for levodopa-treated patients with Parkinson's disease

INTRODUCTION

Levodopa remains the gold standard for treatment of Parkinson's disease (PD). Patients develop complications with disease progression, necessitating adjunctive therapy to control fluctuations in motor and non-motor symptoms and dyskinesia. Knowledge of medication safety and tolerability is critical to ascertain the benefit-risk ratio and select an adjunctive therapy that provides the highest chance for medication adherence. Posing a challenge are the sheer abundance of options, stemming from the development of several new drugs in recent years, as well as differences in commercial drug availability worldwide.

AREAS COVERED

This review evaluates the efficacy, safety, and tolerability of current US FDA-approved pharmacotherapies for levodopa-treated PD patients, including dopamine agonists, monoamine oxidase type-B inhibitors, catechol-O-methyltransferase inhibitors, the N-methyl-D-aspartate receptor antagonist amantadine, and the adenosine receptor antagonist istradefylline. Data were taken from pivotal phase III randomized controlled and post-surveillance studies, when available, that directly led to FDA-approval.

EXPERT OPINION

No strong evidence exists to support use of a specific adjunctive treatment for improving Off time. Only one medication has demonstrated improvement in dyskinesia in levodopa-treated PD patients; however, every patient cannot tolerate it and therefore adjunctive therapy should be tailored to an individual's symptoms and risk for specific adverse effects.

Sustained response in early responders to safinamide in patients with Parkinson's disease and motor fluctuations: A post hoc analysis of the SETTLE study

Safinamide is a selective, reversible, monoamine oxidase B inhibitor for the treatment of patients with Parkinson's disease (PD) and motor fluctuations. This was a post hoc analysis of the SETTLE study, in which patients with PD and motor fluctuations were randomly assigned to 24-week treatment with safinamide (50 mg/day for 2 weeks, increased to 100 mg/day if tolerated) or placebo. In the present analysis, responders were defined according to their treatment responses at Week 2 and Week 24 based on changes in ON-time without troublesome dyskinesia from baseline with cutoffs of 1 hour. It was found that 81% (103/127) of the responders at Week 2 maintained the response through Week 24 in the safinamide group. Other outcomes did not necessarily coincide with the ON-time response; however, “Early” responders who showed a treatment response at both Week 2 and Week 24 had substantial improvements from baseline in OFF-time, UPDRS Part II and III scores, and PDQ-39 summary index scores through Week 24. The safinamide group had a higher proportion of early responders than the placebo group (39% vs 20%, p < 0.0001). At baseline, early responders in the safinamide group had significantly higher UPDRS Part II and III scores, shorter ON-time, and longer OFF-time than the other responder populations. In conclusion, the results of the present post hoc analysis suggest that patients with a short ON-time, severe motor symptoms, and highly compromised activities of daily living can benefit from safinamide early in treatment and over the long term.

Off-time Treatment Options for Parkinson's Disease

Motor fluctuations (MF) are deemed by patients with Parkinson's disease (PD) as the most troublesome disease feature resulting from the increasing impairment in responsiveness to dopaminergic drug treatments. MF are characterized by the loss of a stable response to levodopa over the nychthemeron with the reappearance of motor (and non-motor) parkinsonian clinical signs at various moments during the day and night. They normally appear after a few years of levodopa treatment and with a variable, though overall increasing severity, over the disease course. The armamentarium of first-line treatment options has widened in the last decade with new once-a-daily compounds, including a catechol O-methyltransferase inhibitor - Opicapone-, two MAO-B inhibitors plus channel blocker - Zonisamide and Safinamide and one amantadine extended-release formulation - ADS5012. In addition to apomorphine injection or oral levodopa dispersible tablets, which have been available for a long time, new on-demand therapies such as apomorphine sublingual or levodopa inhaled formulations have recently shown efficacy as rescue therapies for Off-time treatment. When the management of MF becomes difficult in spite of oral/on-demand options, more complex therapies should be considered, including surgical, i.e. deep brain stimulation, or device-aided therapies with pump systems delivering continuous subcutaneous or intestinal levodopa or subcutaneous apomorphine formulation. Older and less commonly used ablative techniques (radiofrequency pallidotomy) may also be effective while there is still scarce data regarding Off-time reduction using a new lesional approach, i.e. magnetic resonance-guided focused ultrasound. The choice between the different advanced therapies options is a shared decision that should consider physician opinion on contraindication/main target symptom, patients' preference, caregiver's availability together with public health systems and socio-economic environment. The choice of the right/first add-on treatment is still a matter of debate as well as the proper time for an advanced therapy to be considered. In this narrative review, we discuss all the above cited aspects of MF in patients with PD, including their phenomenology, management, by means of pharmacological and advanced therapies, on-going clinical trials and future research and treatment perspectives.

Monoamine-oxidase Type B Inhibitors and Cognitive Functions in Parkinson's Disease: Beyond the Primary Mechanism of Action

Symptoms of cognitive impairment are rather common since the early stage of Parkinson's disease (PD); they aggravate with disease progression and may lead to dementia in a significant proportion of cases. Worsening of cognitive symptoms in PD patients depends on the progression of subcortical dopaminergic damage as well as the involvement of other brain neurotransmitter systems in cortical and subcortical regions. Beyond the negative impact on disability and quality of life, the presence and severity of cognitive symptoms may limit adjustments of dopamine replacement therapy along the disease course. This review focuses on the consequences of the administration of monoamine-oxidase type Binhibitors (MAOB-I) on cognition in PD patients. Two drugs (selegiline and rasagiline) are available for the treatment of motor symptoms of PD as monotherapy or in combination with L-DOPA or dopamine agonists in stable and fluctuating patients; a further drug (safinamide) is usable in fluctuating subjects solely. The results of available studies indicate differential effects according to disease stage and drug features. In early, non-fluctuating patients, selegiline and rasagiline ameliorated prefrontal executive functions, similarly to other dopaminergic drugs. Benefit on some executive functions was maintained in more advanced, fluctuating patients, despite the tendency of worsening prefrontal inhibitory control activity. Interestingly, high-dose safinamide improved inhibitory control in fluctuating patients. The benefit of high-dose safinamide on prefrontal inhibitory control mechanisms may stem from its dual mechanism of action, allowing reduction of excessive glutamatergic transmission, in turn secondary to increased cortical dopaminergic input.

[Effect of safinamide on morning-off phenomenon in elderly patients with Parkinson's disease]

AIM

Morning-off is a symptom experienced by patients with Parkinson's disease (PD), which markedly reduces patients' quality of life. The present study evaluated the effect of safinamide on morning-off in elderly PD patients.

METHODS

This observational study included 30 PD patients treated with 50 or 100 mg/day of safinamide in the evening. Using patient-reported outcomes, we evaluated the effect of safinamide on daily/morning ON-time, daily/morning OFF-time, Unified Parkinson's Disease Rating Scale (UPDRS) Part III score, and non-motor symptoms. Data at baseline (treatment start) and at 4, 8, 12, and 16 weeks after baseline were recorded.

RESULTS

The PD patients (75.8±7.5 years old) in this study, who tended to be older than in previous phase 2/3 or 3 studies, may represent real-world Japanese PD patients. Compared with baseline, safinamide significantly increased the daily ON-time at eight weeks and morning ON-time at four weeks. Safinamide significantly reduced the daily OFF-time and morning OFF-time at four weeks. The UPDRS Part III score was significantly reduced by 1 point at 12 weeks. Safinamide showed a tendency to reduce non-motor symptoms, such as anxiety, pain, and depressive feelings. There was no marked difference in these parameters between patients treated with 50 and 100 mg of safinamide.

CONCLUSIONS

Our results suggest that safinamide administered in the evening can benefit elderly patients who experience wearing off, especially morning off, and non-motor symptoms.

Effectiveness and safety of safinamide in routine clinical practice in a Belgian Parkinson's disease population: an open-label, levodopa add-on study

BACKGROUND

Safinamide is a recent multimodal antiparkinsonian drug that inhibits monoamine oxidase B and modulates the glutamatergic system with positive effects on motor and nonmotor symptoms of Parkinson's disease (PD). This post-hoc analysis of the European SYNAPSES study provides first-time data on the use of safinamide in routine clinical practice in Belgium.

OBJECTIVE

To describe the efficacy and safety of safinamide in Belgian PD patients in real-life conditions.

METHODS

Post-hoc analysis of the Belgian cohort from the European SYNAPSES trial, which was an observational, multicenter, retrospective-prospective cohort study. Patients were followed up to 12 months. Analyses were performed in the overall population and according to different criteria such as the age limit (> 75 years), presence or absence of relevant comorbidities, presence or absence of psychiatric conditions such as depression and anxiety, patients on levodopa monotherapy or levodopa in combination with other treatments, patients on rasagiline before inclusion or not.

RESULTS

Of the 172 patients included, 29.2% were > 75 years, 58.9% had relevant comorbidities and 32.7% had psychiatric conditions. Almost all the patients reported motor (98.8%) or non-motor (86.3%) symptoms. During the study, 36.3% of patients reported drug-related reactions. The adverse drug reactions were those already described in the patients' information leaflet. The majority were mild or moderate and completely resolved and no differences were detected between the subgroups of patients. Almost 35% of the patients demonstrated a clinically significant improvement in the UPDRS and 50% of the patients with wearing-off at baseline, did not report wearing-off anymore after one year of treatment. Patients under levodopa monotherapy compared to patients receiving levodopa combined with other antiparkinsonian treatments benefit more from safinamide treatment. Patients switched from rasagiline to safinamide seemed also to benefit more from safinamide treatment.

CONCLUSION

The study confirms the excellent safety and efficacy profile of safinamide, particularly in more vulnerable groups of patients such as the elderly and patients with significant comorbidities or psychiatric conditions such as depression or anxiety.

The Efficacy of Safinamide in the Management of Parkinson's Disease: A Systematic Review

Parkinson's disease (PD) is a chronic neurodegenerative disease that is challenging to treat due to its progressive nature and its weaning response to therapy. Safinamide, a monoamine oxidase type-B inhibitor (MAOB-I), has shown promise in managing dyskinesias caused by levodopa (L-dopa), carbidopa, and PD features such as pain and depression. This systematic review aimed to evaluate safinamide's efficacy as a monotherapy and an add-on in tackling these issues. We composed this systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Our group searched the following databases: Manchester University Library, ScienceDirect, Google Scholar, PubMed, PubMed Central, and MedLine for articles produced in the last ten years using various search terms and criteria, which we outlined in the search strategy and eligibility criteria sections. We excluded 722 out of the initially screened 730 records for multiple reasons, such as titles and abstracts being irrelevant to the topic, articles without free full access, articles originally not in the English language, and articles that did not score 70% or above on their respective quality assessment tools. The studies explored supported safinamide's use in managing motor fluctuations, pain, depression, and improving patients' quality of life.

Collective Expert Perspectives on the Use of Safinamide as Adjunctive Therapy for Parkinson’s Disease: Online-Based Delphi Survey

Background. Safinamide is a selective, reversible monoamine oxidase-B inhibitor with a sodium channel inhibitory effect. Published clinical evidence supports safinamide as an effective therapy for Parkinson’s disease (PD) with wearing-off. However, to date, no consensus recommendations have been available to guide physicians in Asia on the optimal use of safinamide in clinical practice. To summarize opinions on the optimal patient profile and methods of using safinamide in common clinical scenarios, Japanese movement disorder specialists with expertise in PD investigated the perspectives of neurologists and neurosurgeons. Methods. The Delphi panel approach was used to summarize the opinions of panelists. The panel comprised doctors from Japan with extensive clinical practice experience in the use of safinamide (n = 46 at the final round). The consensus was defined as 80% or more agreement between panelists for each scenario at the final round. Results. There was a high level of agreement that patients with the following symptoms are suitable for safinamide treatment such as bradykinesia (100%), rigidity (95.7%), and/or gait disorder (89.1%) based on motor symptoms and PD-related pain (97.8%) and/or depression or apathy (93.5%) based on non-motor symptoms. Morning-off (95.7%), but not dyskinesia (71.7%), also reached consensus. The use of high-dose safinamide (100 mg/day) was recommended when the improvement in PD symptoms is insufficient and increasing the doses of other anti-PD medications is difficult (97.8%) or when the abovementioned non-motor symptoms adversely affect daily life (93.5%). Conclusions. This report provides expert perspectives on the use of safinamide for a wide range of clinical scenarios in Japan.

Monoamine Oxidase-B Inhibitors for the Treatment of Parkinson's Disease: Past, Present, and Future

Monoamine oxidase-B (MAO-B) inhibitors are commonly used for the symptomatic treatment of Parkinson’s disease (PD). MAO-B inhibitor monotherapy has been shown to be effective and safe for the treatment of early-stage PD, while MAO-B inhibitors as adjuvant drugs have been widely applied for the treatment of the advanced stages of the illness. MAO-B inhibitors can effectively improve patients’ motor and non-motor symptoms, reduce “OFF” time, and may potentially prevent/delay disease progression. In this review, we discuss the effects of MAO-B inhibitors on motor and non-motor symptoms in PD patients, their mechanism of action, and the future development of MAO-B inhibitor therapy.

Andrade LA, Ferraz HB, Barbosa ER, Rieder CRDM, da Silva DJ, Chien HF, Capato T, Rosso AL, Souza Lima CF, Bezerra JMF, Nicaretta D, Povoas Barsottini OG, Godeiro-Júnior C, Broseghini Barcelos L, Gisbert Cury R, Spitz M, Azevedo Silva SMC, Della Colletta MV. Guidelines for Parkinson’s disease treatment: consensus from the Movement Disorders Scientific Department of the Brazilian Academy of Neurology - motor symptoms

ABSTRACT The treatment of Parkinson's disease (PD) is challenging, especially since it is considered highly individualized. The Brazilian Academy of Neurology has recognized the need to disseminate knowledge about the management of PD treatment, adapting the best evidence to the Brazilian reality. Thus, the main published treatment guidelines were reviewed based on the recommendations of group from the Movement Disorders Scientific Department of the Brazilian Academy of Neurology.

Systematic Review on Parkinson's Disease Medications, Emphasizing on Three Recently Approved Drugs to Control Parkinson's Symptoms

Parkinson's Disease (PD) is a disease that involves neurodegeneration and is characterised by the motor symptoms which include muscle rigidity, tremor, and bradykinesia. Other non-motor symptoms include pain, depression, anxiety, and psychosis. This disease affects up to ten million people worldwide. The pathophysiology behind PD is due to the neurodegeneration of the nigrostriatal pathway. There are many conventional drugs used in the treatment of PD. However, there are limitations associated with conventional drugs. For instance, levodopa is associated with the on-off phenomenon, and it may induce wearing off as time progresses. Therefore, this review aimed to analyze the newly approved drugs by the United States-Food and Drug Administration (US-FDA) from 2016-2019 as the adjuvant therapy for the treatment of PD symptoms in terms of efficacy and safety. The new drugs include safinamide, istradefylline and pimavanserin. From this review, safinamide is considered to be more efficacious and safer as the adjunct therapy to levodopa as compared to istradefylline in controlling the motor symptoms. In Study 016, both safinamide 50 mg (p = 0.0138) and 100 mg (p = 0.0006) have improved the Unified Parkinson's Disease Rating Scale (UPDRS) part III score as compared to placebo. Improvement in Clinical Global Impression-Change (CGI-C), Clinical Global Impression-Severity of Illness (CGI-S) and off time were also seen in both groups of patients following the morning levodopa dose. Pimavanserin also showed favorable effects in ameliorating the symptoms of Parkinson's Disease Psychosis (PDP). A combination of conventional therapy and non-pharmacological treatment is warranted to enhance the well-being of PD patients.

Characteristics of wearing-off and motor symptoms improved by safinamide adjunct therapy in patients with Parkinson's disease: A post hoc analysis of a Japanese phase 2/3 study

INTRODUCTION

Patients with Parkinson's disease (PD) experience various motor and non-motor symptoms. We conducted a post hoc analysis of a Japanese phase 2/3 study of safinamide (50 or 100 mg/day) in patients with Parkinson's disease and wearing-off to evaluate response according to background factors. Safinamide efficacy against major motor symptoms was also assessed.

METHODS

Multiple regression analyses in safinamide-treated patients (50 or 100 mg/day) assessed changes in daily ON-time without troublesome dyskinesia (hereafter referred to as ON-time) according to baseline clinical variables. Subgroup analyses by baseline Unified Parkinson's Disease Rating Scale (UPDRS) part III score were also conducted. We evaluated cardinal motor symptoms using the UPDRS.

RESULTS

In the multiple regression analysis, changes in ON-time were related to baseline non-motor symptoms (UPDRS part I score) and ON-time in the 50-mg group, but no relationships with non-motor symptoms were observed in the 100-mg group. Additionally, in the subgroup analysis of patients with more severe motor symptoms (UPDRS part III score > 20), a significant improvement in ON-time was observed only with 100 mg/day (p = 0.01). At both doses, safinamide significantly improved cardinal motor symptom scores (bradykinesia, rigidity, tremor, axial symptoms, and gait disturbances).

CONCLUSIONS

The observed response profile to the 50-mg/day dose may be related to baseline non-motor symptoms, but this was not true for the 100-mg/day dose. Both safinamide doses improved major motor symptoms in levodopa-treated patients with PD.

Effects of safinamide on pain in patients with fluctuating Parkinson's disease

BACKGROUND

Non-motor symptoms (NMS) are integral to Parkinson's Disease (PD) and management remains a challenge. Safinamide is a novel molecule in relation to addressing NMS due to its multifocal mechanism of action with both dopaminergic and non-dopaminergic properties.

OBJECTIVE

To investigate the efficacy of safinamide on NMS and its burden in PD patients with motor fluctuations after 6 months of treatment.

METHODS

This observational, multicenter, open-label, pilot study assessed a wide range of NMS using the following rating scales, NMSS (non-motor symptom scale), KPPS (King's PD pain scale), HADS (hospital anxiety and depression scale), PDQ-8 (Parkinson's disease quality of life questionnaire), and PDSS-2 (Parkinson's disease sleep scale), EuroQol-5D 3 level version (EQ-5D-3L), CGI-I (clinical global impression of improvement), and PGI-C (patient global impression of change). Motor examination using UPDRS part III (Unified Parkinson's disease rating scale, motor examination), UPDRS IV (complications of therapy) and Hoehn and Yahr staging were also obtained.

RESULTS

27 patients were included in the analysis and were evaluated at baseline and ≥ 6 months after safinamide treatment. 26 patients had a daily maintenance dose of 100 mg and 1 patient a daily dose of 50 mg. Significant improvements in UPDRS IV, KPPS item 5 (region-specific "off" dystonia), KPPS domain 3 (items 4-6, fluctuation related pain) and KPPS total score were observed after treatment with safinamide, while maintaining stable dopaminergic medication. No statistically significant differences were found in NMSS, HADS, PDSS-2, EQ-5D-3L, and PDQ-8 after treatment.

CONCLUSIONS

Our results suggest that safinamide may have a beneficial effect on pain, a key unmet need in fluctuating PD patients.

The Current Evidence for the Use of Safinamide for the Treatment of Parkinson's Disease

Introduction

Parkinson’s therapeutic interventions are only symptomatic. An optimal treatment should therefore address the largest number of motor and non-motor symptoms, to manage patients at best. Safinamide is one of the most recent approved drugs for fluctuating patients, in add-on to levodopa, that remains the gold standard treatment. It has a unique mechanism of action, both dopaminergic (as MAO-B inhibitor) and glutamatergic (through Na⁺ channel blockade). Results from Phase III trials, post-hoc analyses and real-life experiences suggest a beneficial effect on motor (such as tremor, bradykinesia, rigidity and gait) and non-motor (pain, mood, sleep) symptoms.

Areas Covered

Here, the authors discuss clinical efficacy and safety of safinamide, identifying the patients’ profiles that could benefit most. A search in PubMed was performed in September 2020, with no time limits. Publications’ abstracts were reviewed.

Conclusion

Safinamide is peculiar due to its double mechanism of action. Its benefits in improving motor functions and fluctuations, and some non-motor symptoms, could have a valuable impact on patients’ quality of life (QoL), together with its safety profile.

Opicapone for Parkinson's disease: clinical evidence and future perspectives

Since 2016, opicapone (OPC), a potent third-generation, long-acting, once-daily, peripheral catechol-O-methyltransferase inhibitor, is approved as an add-on to levodopa in Parkinson's disease patients with motor fluctuations. OPC 50 mg has showed to be able in reducing OFF time by an average of about 60 min daily compared with placebo, to further reduce OFF-time of about 39 min, when switched from ENT to OPC and to be safe. These beneficial effects of OPC were maintained for 1 year. Recently, several post hoc analysis and few pilot observational open-label studies, have suggested its efficacy and wider applicability for different phenotypes of motor complications and for Parkinson's disease stages. Here we review OPC applicability and perspectives, in the light of the more recently published analysis.

Safinamide Improves Non-Motor Symptoms Burden in Parkinson's Disease: An Open-Label Prospective Study

Some studies observed a benefit of Parkinson's disease (PD) patients after treatment with safinamide in some non-motor symptoms (NMSs). The aim of this study was to analyze the effectiveness of safinamide on NMS burden in PD. SAFINONMOTOR (an open-label study of the effectiveness of safinamide on non-motor symptoms in Parkinson's disease patients) is a prospective open-label single-arm study conducted in five centers from Spain. The primary efficacy outcome was the change from baseline (V1) to the end of the observational period (6 months) (V4) in the non-motor symptoms scale (NMSS) total score. Between May/2019 and February/2020 50 patients were included (age 68.5 ± 9.12 years; 58% females; 6.4 ± 5.1 years from diagnosis). At 6 months, 44 patients completed the follow-up (88%). The NMSS total score was reduced by 38.5% (from 97.5 ± 43.7 in V1 to 59.9 ± 35.5 in V4; p < 0.0001). By domains, improvement was observed in sleep/fatigue (-35.8%; p = 0.002), mood/apathy (-57.9%; p < 0.0001), attention/memory (-23.9%; p = 0.026), gastrointestinal symptoms (-33%; p = 0.010), urinary symptoms (-28.3%; p = 0.003), and pain/miscellaneous (-43%; p < 0.0001). Quality of life (QoL) also improved with a 29.4% reduction in the PDQ-39SI (from 30.1 ± 17.6 in V1 to 21.2 ± 13.5 in V4; p < 0.0001). A total of 21 adverse events in 16 patients (32%) were reported, 5 of which were severe (not related to safinamide). Dyskinesias and nausea were the most frequent (6%). Safinamide is well tolerated and improves NMS burden and QoL in PD patients with severe or very severe NMS burden at 6 months.

A European Observational Study to Evaluate the Safety and the Effectiveness of Safinamide in Routine Clinical Practice: The SYNAPSES Trial

BACKGROUND

Safinamide modulates both dopaminergic and glutamatergic systems with positive effects on motor and non-motor symptoms of Parkinson's disease (PD). The drug utilization study SYNAPSES was designed to investigate the use of safinamide in routine clinical practice, as recommended by the European Medicines Agency.

OBJECTIVE

To describe the occurrence of adverse events in PD patients treated with safinamide in real-life conditions.

METHODS

The SYNAPSES trial is an observational, European, multicenter, retrospective-prospective cohort study. Patients were followed up to 12 months with analyses performed in the overall population and in patients aged >75 years, with relevant comorbidities and with psychiatric conditions.

RESULTS

Of the 1610 patients included, 82.4% were evaluable after 12 months with 25.1% of patients >75 years, 70.8% with relevant comorbidities and 42.4% with psychiatric conditions. During observation 45.8% patients experienced adverse events, 27.7% patients had adverse drug reactions and 9.2% patients had serious adverse events. The adverse events were those already described in the patients' information leaflet. The majority were mild or moderate and completely resolved and no differences were detected between the subgroup of patients. Clinically significant improvements were seen in the UPDRS motor score and in the UPDRS total score in ≥40% of patients, according to the criteria developed by Shulman et al.Conclusion:The SYNAPSES study confirms the good safety profile of safinamide even in special groups of patients. Motor complications and motor scores improved with clinically significant results in the UPDRS scale maintained in the long-term.

A case study of foliglurax, the first clinical mGluR4 PAM for symptomatic treatment of Parkinson's disease: translational gaps or a failing industry innovation model?

INTRODUCTION

Approximately 40% of Parkinson's disease (PD) patients that take mostly dopamine receptor agonists for motor fluctuations, experience the return of symptoms between regular doses. This is a phenomenon known as 'OFF periods.' Positive allosteric modulators (PAMs) of metabotropic glutamate receptor 4 (mGluR4) are a promising non-dopaminergic mechanism with potential to address the unmet need of patients suffering from OFF periods. Foliglurax is the first mGluR4 PAM that has advanced into clinical testing in PD patients.

AREAS COVERED

We summarize the chemistry, pharmacokinetics, and preclinical pharmacology of foliglurax. Translational PET imaging studies, clinical efficacy data, and a competitive landscape analysis of available therapies are presented to the readers. In this Perspective article, foliglurax is used as a case study to illustrate the inherent R&D challenges that companies face when developing drugs. These challenges include the delivery of drugs acting through novel mechanisms, long-term scientific investment, and commercial success and shorter-term positive financial returns.

EXPERT OPINION

Failure to meet the primary and secondary endpoints in a Phase 2 study led Lundbeck to discontinue the development of foliglurax. Understanding the evidence supporting compound progression into Phase 2 will enable the proper assessment of the therapeutic potential of mGluR4 PAMs.

Safinamide in the treatment of Parkinson's disease

The deficiency pattern of neurotransmitters is heterogeneous in patients with Parkinson's disease. Consequence is an individual variable expression of motor and nonmotor features. They respond to agents with a broader spectrum of mode of actions, whereas dopamine substitution only targets impaired motor behavior. The pharmacological profile of safinamide includes reversible monoamine oxidase B inhibition and modulation of voltage-dependent sodium- and calcium channels with consecutive decline of glutamate release. Safinamide improves motor and nonmotor symptoms. Combination of safinamide with the catechol-O-methyltransferase inhibitor opicapone in one capsule is a promising future treatment alternative, which simplifies drug therapy in Parkinson's disease. Both agents complement each other in terms of application mode and efficacy on motor complications as adjuncts to levodopa therapy.

Long-term safety and efficacy of safinamide as add-on therapy in levodopa-treated Japanese patients with Parkinson's disease with wearing-off: Results of an open-label study

INTRODUCTION

Safinamide, a selective, reversible monoamine oxidase B inhibitor with a sodium channel inhibitory effect, improves symptoms in advanced Parkinson's disease (PD). This study aimed to confirm the long-term safety and efficacy of safinamide in Japanese PD patients with wearing-off.

METHODS

Japanese PD patients aged ≥30 years with wearing-off were eligible. The primary efficacy endpoint was change from baseline in the mean daily ON-time without troublesome dyskinesias at 52 weeks of treatment. Other efficacy endpoints included changes from baseline in mean daily OFF-time and unified Parkinson's disease rating scale (UPDRS) and PDQ-39 scores.

RESULTS

In total, 203 patients entered the study, and 142 completed the 52-week treatment. Adverse events (AEs) occurred in 78.3% of patients, with nasopharyngitis (20.7%) and dyskinesias (17.7%) as the most common; serious AEs occurred in 17.2%, causing discontinuation in 10.8%. At Week 52, the mean daily ON-time without troublesome dyskinesias increased from baseline by 1.42 h. Change from baseline in mean daily OFF-time was -1.40 h, and that in the UPDRS Part III score in the ON-phase was -6.20.

CONCLUSIONS

As adjunctive treatment with levodopa, safinamide was safe, well tolerated, and effective in improving ON-time and other PD symptoms at 52 weeks.

Development of an adverse drug event network to predict drug toxicity

Despite of their therapeutic effects, drug's exposure may have negative effects on human health such as adverse drug reaction (ADR) and side effects (SE). Adverse drug events (ADEs), that correspond to an event occurring during the drug treatment (i.e. ADR and SE), is not necessarily caused by the drug itself, as this is the case with medical errors and social factors. Due to the complexity of the biological systems, not all ADEs are known for marketed drugs. Therefore, new and effective methods are needed to determine potential risks, including the development of computational strategies. We present an ADE association network based on 90,827 drug-ADE associations between 930 unique drug and 6221 unique ADE, on which we implemented a scoring system based on a pull-down approach for prediction of drug-ADE combination. Based on our network, ADEs proposed for three drugs, safinamide, sonidegib, rufinamide are further discussed. The model was able to identify, already known drug-ADE associations that are supported by the literature and FDA reports, and also to predict uncharacterized associations such as dopamine dysregulation syndrome, or nicotinic acid deficiency for the drugs safinamide and sonidegib respectively, illustrating the power of such integrative toxicological approach.

Treatment of Parkinson's Disease by MAO-B Inhibitors, New Therapies and Future Challenges - A Mini-Review

BACKGROUND

One of the most prevalent neurodegenerative diseases with increasing age is Parkinson's disease (PD). Its pathogenesis is unclear and mainly confined to glutamate toxicity and oxidative stress. The dyskinesia and motor fluctuations and neuroprotective potential are the major concerns which are still unmet in PD therapy.

OBJECTIVE

This article is a capsulization of the role of MAO-B in the treatment of PD, pharmacological properties, safety and efficiency, clinical evidence through random trials, future therapies and challenges.

CONCLUSION

MAO-B inhibitors are well tolerated for the treatment of PD because of their pharmacokinetic properties and neuroprotective action. Rasagiline and selegiline were recommended molecules for early PD and proven safe and provide a modest to significant rise in motor function, delay the use of levodopa and used in early PD. Moreover, safinamide is antiglutamatergic in action. When added to Levodopa, these molecules significantly reduce the offtime with a considerable improvement of non-motor symptoms. This review also discusses the new approaches in therapy like the use of biomarkers, neurorestorative growth factors, gene therapy, neuroimaging, neural transplantation, and nanotechnology. Clinical evidence illustrated that MAOB inhibitors are recommended as monotherapy and added on therapy to levodopa. A large study and further evidence are required in the field of future therapies to unwind the complexity of the disease.

A Spanish Consensus on the Use of Safinamide for Parkinson's Disease in Clinical Practice

Safinamide is an approved drug for the treatment of fluctuations in Parkinson's disease (PD). Scarce data are available on its use in clinical practice. A group of Spanish movement disorders specialists was convened to review the use of safinamide across different clinical scenarios that may guide neurologists in clinical practice. Eight specialists with recognized expertise in PD management elaborated the statements based on available evidence in the literature and on their clinical experience. The RAND/UCLA method was carried, with final conclusions accepted after a 2-round modified Delphi process. Higher level of agreement between panellists was reached for the following statements. Safinamide significantly improves mean daily ON time without troublesome dyskinesias [corrected]. Adjunctive treatment with safinamide is associated with motor improvements in patients with mid-to-late PD. The efficacy of safinamide on motor fluctuations is maintained at long-term, with no increase over time in dyskinesias severity. The clinical benefits of safinamide on pain and depression remain unclear. Safinamide presents a similar incidence of adverse events compared with placebo. The efficacy and safety of safinamide shown in the pivotal clinical trials are reproduced in clinical practice, with improvement of parkinsonian symptoms, decrease of daily OFF time, control of dyskinesias at the long term, and good tolerability and safety.

Long-Term Efficacy of Safinamide on Symptoms Severity and Quality of Life in Fluctuating Parkinson's Disease Patients

BACKGROUND

Parkinson's disease (PD) is characterized by a wide range of motor and non-motor symptoms. Levodopa is still the most effective drug; however, its long-term use is associated with motor complications which may deteriorate patient's quality of life. Safinamide is a unique treatment modulating both dopaminergic and glutamatergic systems. Previous results from two six months, double-blind, placebo-controlled studies demonstrated that safinamide has positive effects on both motor functions and quality of life in PD patients.

OBJECTIVE

To investigate the effects of safinamide 100 mg/day over two-year treatment on PD symptoms severity and quality of life, using data from the study 018.

METHODS

Data from 352 patients were analyzed to evaluate the effects of safinamide on OFF time and ON time (with no or non-troublesome dyskinesia) in the overall population and in subgroups of patients (receiving levodopa monotherapy or with other anti-Parkinson therapies), and the effects of safinamide on motor symptoms/clinical fluctuations (by means of UPDRS III and IV) and on health-related quality of life (using UPDRS II and PDQ-39 summary index score).

RESULTS

Safinamide, administered as add-on to standard therapy in fluctuating PD patients, significantly improved motor symptoms and clinical fluctuations in the overall population and in some subgroups of patients. Additionally, safinamide improved quality of life and activities of daily living, maintaining the efficacy in the long-term.

CONCLUSIONS

The findings of these analyses suggest that safinamide may be considered an appropriate adjunct therapy in patient not sufficiently controlled. Further investigations are desirable to confirm these results in usual care setting.

Safinamide in Clinical Practice: A Spanish Multicenter Cohort Study

Background: Safinamide is an approved drug for the treatment of motor fluctuations of Parkinson's Disease (PD) patients with a potential benefit on non-motor symptoms (NMS). Methods: A retrospective multicenter cohort study was conducted, in which the clinical effect of safinamide on both motor and NMS was assessed by the Clinical Global Impression of Change scale. Furthermore, we assessed the appearance of adverse events (AEs) and its effect on dyskinesia, that were also recorded in non-fluctuating PD patients and in those previously treated with rasagiline. Results: We included 213 PD patients who received safinamide in addition to their regular levodopa therapy. Thirty-five withdrew prematurely from safinamide, mainly because of AEs. Out of 178, clinical improvement on motor and NMS was found in 76.4% and 26.2%, respectively. A total of 44 reported AEs of mild intensity. We did not find a difference concerning the clinical benefit or AEs when comparing either patients who had or had not been taking Monoamine Oxidase B Inhibitor (MAOB-I) previously or between patients with and without motor complications. Conclusions: Safinamide is an effective and safe add-on to levodopa drug for PD patients. Moreover, safinamide could elicit an additional clinical improvement in PD patients previously treated with other MAOB-I and in non- fluctuating patients with suboptimal motor control.

Rasagiline and safinamide as a dopamine-sparing therapy for Parkinson's disease

OBJECTIVES

To evaluate whether the prescription of monoamine oxidase B inhibitors (MAOB-I), rasagiline and safinamide, contributes to the reduction of levodopa and/or dopamine agonists (DA) dose in order to minimize adverse effects.

MATERIALS AND METHODS

A total of 724 patients with Parkinson's disease (PD) have been prospectively included in our database since the year 2000, representing a total of 5124 visits. For each patient and visit, antiparkinsonian treatment was recorded. In the presence of rasagiline and safinamide, we analysed the evolution of levodopa equivalent dose (LED) and LED for DA (LED-DA).

RESULTS

The data obtained from the 1664 visits between 2006 and 2010 (321 patients) and the 1709 visits between 2014 and 2018 (403 patients) were analysed in order to assess the impact of the introduction of rasagiline and safinamide, respectively. The annual mean LED remained stable without statistically significant differences. In the first period (impact of rasagiline), the annual mean LED-DA in 2010 was significantly higher than in 2006 (P = 0.001). In the second period (impact of safinamide), the annual mean LED-DA in 2018 was significantly lower than in 2014 (P = 0.002). A repeated-measure analyses of LED-DA including only patients who had taken safinamide showed a statistically significant decrease in LED-DA (P = 0.027).

CONCLUSIONS

The introduction of MAOB-I in the overall treatment of PD as part of routine clinical practice has not helped to reduce annual mean LED. However, safinamide reduces annual mean LED-DA and may be linked to a reduction in dose-dependent adverse effects in the long term.

Adjunctive Therapies in Parkinson's Disease: How to Choose the Best Treatment Strategy Approach

End-of-dose motor fluctuations are regarded as one of the core troublesome symptoms by patients with Parkinson's disease (PD). Treatment of levodopa (L-dopa)-induced motor fluctuations is still an unmet medical need. L-dopa is the gold standard in the treatment of motor PD symptoms; notwithstanding, a wide range of adjunct therapies are currently available for the treatment of end-of-dose motor fluctuations. Additionally, device-aided therapies, such as deep brain stimulation, L-dopa-carbidopa intestinal gel infusion, and on-demand injection or continuous apomorphine infusion, may be considered when oral treatments are not sufficient to control motor fluctuations. In spite of the several evidence-based reviews and guidelines available, there is no agreement on which add-on therapy should be started first or its optimal timing. Equally challenging is the choice and timing between device-aided therapies. Herein, we propose a general overview of oral and device-aided treatments for PD patients with end-of-dose motor fluctuations, offering two possible algorithms that can guide clinicians during the therapeutic decision process.

Safinamide in the management of patients with Parkinson's disease not stabilized on levodopa: a review of the current clinical evidence

Safinamide (Xadago^®) is a novel medication with both dopaminergic and non-dopaminergic effects, approved first by the European Commission and more recently by the US Food and Drug Administration (FDA) as an adjunctive treatment to carbidopa/levodopa in patients with mid- to late-stage Parkinson’s disease (PD) and motor fluctuations. It works through multiple mechanisms, namely as a reversible selective monoamine oxidase-B inhibitor and through modulation of glutamate release. Safinamide is extensively metabolized via oxidation to several inactive metabolites that are excreted primarily through the urine. Several large Phase III clinical trials of patients with advanced PD with motor fluctuations have shown that safinamide, administered orally at doses of 50–100 mg daily, increased ON time with no or non-troublesome dyskinesia, decreased daily OFF time, improved overall motor function (as measured by Unified Parkinson’s Disease Rating Scale [UPDRS] part III total score), and quality of life (as measured by Clinical Global Impression-Change and 39-item Parkinson’s Disease Questionnaire). In large clinical trials of patients with early PD on a single dopamine agonist, safinamide administered orally at a dose of 100 mg daily improved overall motor function as measured by UPDRS part III total score; however, some of the results reported were exploratory. Safinamide is generally well-tolerated and safe, with few to no treatment-related adverse events. Safinamide does not cause new or worsening dyskinesia and may be able to reduce this symptom in patients reporting it at baseline. Evidence suggests that safinamide is a good option for add-on therapy to carbidopa/levodopa in patients with advanced PD with motor complications, but there is still insufficient evidence to recommend it as monotherapy or add-on therapy in patients with early PD.

▼ Safinamide for Parkinson's disease

▼ Safinamide (Xadago - Zambon S.p.A) is a monoamine-oxidase B (MAO-B) inhibitor licensed as add-on therapy for people with idiopathic Parkinson's disease who are experiencing motor fluctuations with levodopa.¹ Currently there is no cure for Parkinson's disease and drugs are used to reduce motor symptoms and improve daily activities.^2,3 Here, we review the evidence for this MAO-B inhibitor.

Safinamide: a new hope for Parkinson's disease?

The loss of dopaminergic neurons (DAn) and reduced dopamine (DA) production underlies the reasoning behind the gold standard treatment for Parkinson's disease (PD) using levodopa (L-DOPA). Recently licensed by the European Medicine Agency (EMA) and US Food and Drug Administration (FDA), safinamide [a monoamine oxidase B (MOA-B) inhibitor] is an alternative to L-DOPA; as we discuss here, it enhances dopaminergic transmission with decreased secondary effects compared with L-DOPA. In addition, nondopaminergic actions (neuroprotective effects) have been reported, with safinamide inhibiting glutamate release and sodium/calcium channels, reducing the excitotoxic input to dopaminergic neuronal death. Effects of safinamide have been correlated with the amelioration of non-motor symptoms (NMS), although these remain under discussion. Overall, safinamide can be considered to have potential antidyskinetic and neuroprotective effects and future trials and/or studies should be performed to provide further evidence for its potential as an anti-PD drug.

Old and new challenges in Parkinson's disease therapeutics

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the degeneration of dopaminergic neurons and/or loss od neuronal projections, in several dopaminergic networks. Current treatments for idiopathic PD rely mainly on the use of pharmacologic agents to improve motor symptomatology of PD patients. Nevertheless, so far PD remains an incurable disease. Therefore, it is of utmost importance to establish new therapeutic strategies for PD treatment. Over the last 20 years, several molecular, gene and cell/stem-cell therapeutic approaches have been developed with the aim of counteracting or retarding PD progression. The scope of this review is to provide an overview of PD related therapies and major breakthroughs achieved within this field. In order to do so, this review will start by focusing on PD characterization and current treatment options covering thereafter molecular, gene and cell/stem cell-based therapies that are currently being studied in animal models of PD or have recently been tested in clinical trials. Among stem cell-based therapies, those using MSCs as possible disease modifying agents for PD therapy and, specifically, the MSCs secretome contribution to meet the clinical challenge of counteracting or retarding PD progression, will be more deeply explored.

Recent advances in treating Parkinson's disease

This article summarizes (1) the recent achievements to further improve symptomatic therapy of motor Parkinson’s disease (PD) symptoms, (2) the still-few attempts to systematically search for symptomatic therapy of non-motor symptoms in PD, and (3) the advances in the development and clinical testing of compounds which promise to offer disease modification in already-manifest PD. However, prevention (that is, slowing or stopping PD in a prodromal stage) is still a dream and one reason for this is that we have no consensus on primary endpoints for clinical trials which reflect the progression in prodromal stages of PD, such as in rapid eye movement sleep behavior disorder (RBD) —a methodological challenge to be met in the future.

Through scaffold modification to 3,5-diaryl-4,5-dihydroisoxazoles: new potent and selective inhibitors of monoamine oxidase B

3,5-Diaryl-4,5-dihydroisoxazoles were synthesized and evaluated as monoamine oxidase (MAO) enzyme inhibitors and iron chelators. All compounds exhibited selective inhibitory activity towards the B isoform of MAO in the nanomolar concentration range. The best performing compound was preliminarily evaluated for its ability to bind iron II and III cations, indicating that neither iron II nor iron III is coordinated. The best compounds racemic mixtures were separated and single enantiomers inhibitory activity evaluated. Furthermore, none of the synthesised compounds exhibited activity towards MAO A. Overall, these data support our hypothesis that 3,5-diaryl-4,5-dihydroisoxazoles are promising scaffolds for the design of neuroprotective agents.

Safinamide: A Review in Parkinson's Disease

Safinamide (Xadago^®) is an orally active, selective, reversible monoamine oxidase-B inhibitor with both dopaminergic and non-dopaminergic (glutamatergic) properties. In the EU, safinamide is approved for the treatment of mid- to late-stage fluctuating Parkinson's disease (PD) as add-on therapy to a stable dose of levodopa alone or in combination with other PD medications. Safinamide 50-100 mg/day administered as a fixed or flexible dose significantly increased daily 'on' time without dyskinesia (primary endpoint) in patients with mid- to late-stage PD with motor fluctuations in 24-week, placebo-controlled clinical trials. Other outcomes, including motor function, overall clinical status and health-related quality of life, were also generally improved with safinamide. Furthermore, in an 18-month extension of one study, although dyskinesia (primary endpoint) was not significantly improved with safinamide relative to placebo, treatment benefits in other outcomes were generally sustained over 24 months of treatment. Safinamide was generally well tolerated in clinical trials; dyskinesia was the most common adverse event. Although further studies are needed, including comparative and long-term studies, current evidence indicates that safinamide extends the treatment options available for use as add-on therapy to levodopa and other PD medications in patients with mid- to late-stage PD experiencing motor fluctuations.