Levodopa–entacapone–carbidopa intestinal gel infusion in advanced Parkinson’s disease: real-world experience and practical guidance

Glutathione S-transferase polymorphisms (GSTM1/GSTT1) outcomes in clinical profile and treatment responsiveness among Tunisian cohort of Parkinson's disease

Glutathione S-transferases are involved in the oxidative stress which contributes to the pathogenesis of Parkinson's disease (PD). our aim was to investigate the influence of GSTM1 and GSTT1 polymorphisms on the clinical features and treatments outcomes among PD Tunisian patients. We included 300-PD patients followed in neurology department at Razi-University-hospital. GSTM1 and GSTT1 were screened using PCR methods. Correlation between the clinical phenotype and the genotypes was then assessed after adequate parameters adjustment. Individuals carrying inactive GSTT1/GSTM1 were estimated to have 2.5-fold higher risk of developing PD, p = 0.035. The demographic and clinical baseline analysis of GSTM1 polymorphism revealed significant association between the inactive gene and development of tremor as first symptoms (p = 0.046), further, it was correlated to asymmetric start (p = 0.044). The evaluation of the impact of GSTM1/GSTT1 activity among PD at last follow-up revealed the significant variability of motor impairment among cases carrier of the active genes (p = 0.048). As patients with inactive GSTM1/GSTT1 had higher UPDRS-III score. Additionally, higher frequency of cases with good treatment responsiveness was reported among PD with active GSTM1/GSTT1 (p = 0.038).No motor complications were observed among PD by considering the GSTs genotypes (p > 0.05). Finally, we noted significant impairment of memory among cases with inactivate GSTs (p = 0.04), attention deficit (p = 0.013) and impaired judgement (p = 0.0031). This study represents one of the most comprehensive and extensive investigation to date regarding the influence of GSTT1/GSTM1 genotype among PD patients.We speculate that the impact of GSTT1/GSTM1 on PD progression may occur through a cumulative effect, potentially not manifesting during the initial PD stages. Further studies are necessary to validate our conclusions.

The Catechol O-Methyltransferase Inhibitor Entacapone in the Treatment of Parkinson's Disease: Personal Reflections on a First-in-Class Drug Development Programme 40 Years On

In the 1980s, Orion Pharma, then a mid-ranking Nordic area pharmaceutical company, established a drug development programme on the inhibition of catechol O-methyltransferase (COMT). This enzyme, which plays an important role in the inactivation of catecholamine neurotransmitters and drugs with a catechol structure, thus came under consideration as a target in the innovative translational and clinical programme we describe in this historical review. The starting point was the conjecture that a peripherally acting COMT inhibitor might improve entry of levodopa into the brain. This had potentially significant implications for the medical treatment of Parkinson's disease (PD). The rationale was that more efficient delivery of levodopa to the brain might allow the high therapeutic doses of levodopa to be reduced and the dose interval to be extended. Elucidation of structure-activity relations paved the way for the discovery and development of entacapone, a 5-nitrocatechol that was a potent and highly specific inhibitor of COMT. Experience in phase III clinical trials established that entacapone, used as an adjunct to regular or controlled-release levodopa preparations (also including a peripherally acting dopa-decarboxylase inhibitor), increased ON-time and reduced OFF-time and improved clinical condition in patients with PD experiencing wearing-off, often with a reduced daily levodopa dose. Several of these studies also identified that entacapone improved patients' quality of life and was cost-effective. Subsequently, entacapone has been amalgamated into a triple-combination preparation (Stalevo®) with levodopa and carbidopa to create a flexible and convenient drug therapy for patients with PD who have end-of-dose motor fluctuations not stabilised on levodopa/dopa-decarboxylase inhibitor treatment. This review offers a historical perspective on a successful programme of drug development by researchers who played central roles in the progress from exploratory hypothesis to registered pharmaceutical product.

Subcutaneous Levodopa: A New Engine for the Vintage Molecule

The management of Parkinson's disease (PD) continues to evolve with advancements in non-oral levodopa-based therapies aiming to provide continuous drug delivery (CDD). Such therapies address the challenges posed by the emergence of motor fluctuations, dyskinesias, and non-motor fluctuations (NMF) associated with oral levodopa administration and contributing to define the advanced stage of PD. The key focus of this review is placed on subcutaneous foslevodopa/foscarbidopa (Foslevodopa/foscarbidopa) infusion, showcasing its recent clinical availability and efficacy in providing continuous levodopa delivery. While providing an overview of the other non-oral levodopa-based CDD systems, such as intrajejunal levodopa-carbidopa infusion and levodopa-entacapone-carbidopa infusion, we highlight the current promising evidence for Foslevodopa/foscarbidopa to improve, for example, "on time" without troublesome dyskinesia and reducing "off time" in people with advanced PD. Additionally, Foslevodopa/foscarbidopa demonstrates potential in managing early morning off periods, sleep quality and other motor and non-motor symptoms. Moreover, other non-oral CDD options such as ND0612 and DIZ102/DIZ101 are discussed, with focus on their pharmacokinetics/pharmacodynamics, efficacy, and safety profiles. While these advancements present new therapeutic avenues, long-term observational studies are warranted to elucidate their impact on existing PD therapies. Overall, this review provides insights into the evolving landscape of non-oral CDD therapies and offers a pragmatic approach for their integration into clinical practice.

Freezing of gait: pharmacological and surgical options

PURPOSE OF REVIEW

The primary aim of this review is to describe and update the pathophysiological and relevant therapeutic strategies for freezing of gait (FoG) in patients with Parkinson's disease (PD).

RECENT FINDINGS

FoG presumably involves dysfunction of multiple cortical and subcortical components, including dopaminergic and nondopaminergic circuits. In this regard, levodopa and physical therapy represent the first-choice therapeutic options for PD patients with FoG. However, the relationship between FoG and levodopa is not fully predictable. For those patients with levodopa-resistant FoG, there is promising but still controversial data on the benefits of bilateral high-frequency transcranial magnetic stimulation and deep brain stimulation on the subthalamic nuclei, substantia nigra pars reticulata, pedunculopontine nucleus, and the Fields of Forel. On the other hand, general exercise, gait training with a treadmill, focus attention on gait training, and conventional physiotherapy have demonstrated moderate to large benefits in FoG.

SUMMARY

FOG requires different treatment strategies. The inclusion of adequate detection and prediction of FoG combined with double-blind, and statistically powered protocols are needed to improve patients' quality of life, the motor and nonmotor symptoms and societal burden associated with FoG.

Monotherapy with infusion therapies - useful or not?

Infusion pump-based therapies are an effective treatment option for patients with advanced Parkinson´s disease. Achieving monotherapy with infusion-based therapies could simplify the treatment regimen, provide better medication adherence, reduce adverse events and drug interactions. This review presents the literature data on the efficacy, safety, and achievability of monotherapy with all available infusion-based therapies, including apomorphine, levodopa-carbidopa-intestinal gel (LCIG), levodopa-entacapone-carbidopa intestinal gel (LECIG), and foslevodopa-foscarbidopa (LDp/CDp). In summary, monotherapy is achievable and effective in most patients on intestinal levodopa infusion therapy and in some patients on apomorphine infusion. There is a need for further investigation of monotherapy compared to polytherapy, especially in new pump treatment options (LECIG and LDp/CDp). Future research should reveal which patients on infusion-based therapies could benefit from monotherapy, including identification of potential baseline predictors of achieving monotherapy in patients treated with specific infusion-based therapies.

The Impact of LRRK2 G2019S on Parkinson's Disease: Clinical Phenotype and Treatment in Tunisian Patients

OBJECTIVE

LRRK2-G2019S is the most frequent mutation in North African Parkinson's disease (PD) patients. Data on its impact on disease progression and treatment response remain elusive. Therefore, we investigated the clinical features, treatments, and complications of PD in Tunisian patients according to their LRRK2-G2019S profile.

METHODS

This longitudinal retrospective study was performed in the Department of Neurology, Razi University Hospital. We included clinically diagnosed PD patients according to the Movement Disorders Society criteria and reviewed their medical records for clinical, treatment, and neuropsychological assessments. All patients were screened for the LRRK2-G2019S mutation using Sanger sequencing. The correlation between LRRK2-G2019S and clinical PD features was evaluated.

RESULTS

We included 393 PD patients, 41.5% of whom had LRRK2-G2019S mutations. Patients with mutations were younger (p = 0.017), and female PD patients had a greater mutation frequency (p = 0.008). Mutation carriers exhibited distinct clinical features, with a greater frequency of postural instability gait difficulty forms (adjusted-p < 0.001). During disease progression, carriers showed a faster annual progression in the Unified Parkinson's Disease Rating Scale Section III scores (adjusted-p = 0.009), and significantly higher levodopa equivalent dose values in later stages (1060.81 vs. 877.83 for 6-8 years). Motor complications, such as dyskinesia (adjusted-p < 0.001) and motor fluctuations (31.9% vs. 25.7%, adjusted-p < 0.001), were more prevalent in carriers, particularly in the later stages. LRRK2-G2019S carriers also exhibited a lower prevalence of non-motor symptoms, including episodic memory (adjusted-p < 0.001), attention (adjusted-p < 0.001), and dysexecutive disorders (adjusted-p = 0.038), as well as neuropsychiatric symptoms and dysautonomic signs.

CONCLUSION

The present study demonstrated that the variability of the clinical profile among Tunisian PD patients was explained by the incomplete penetrance of LRRK2-G2019S, which increased with age. Further studies using biomarker and disease progression data are necessary to improve PD management.

Levodopa-Carbidopa-Entacapone Intestinal Gel in Advanced Parkinson Disease: A Multicenter Real-Life Experience

BACKGROUND

For Parkinson disease (PD) patients who have been diagnosed with advanced disease that can no longer be effectively controlled with optimized oral or transdermal medications, a range of device-aided therapies (DAT) are available, comprising either deep brain stimulation or infusion therapies providing continuous dopaminergic stimulation. Levodopa-entacapone-carbidopa intestinal gel (LECIG) infusion is the latest DAT for advanced PD (APD) that was approved in Romania in 2021.

STUDY QUESTION

What is the experience to date in real-world clinical practice in Romania regarding the efficacy and tolerability of LECIG in APD?

STUDY DESIGN

A retrospective evaluation of 74 APD patients treated with LECIG at 12 specialized APD centers in Romania.

MEASURES AND OUTCOMES

Demographic data and various clinical parameters were recorded, including Mini Mental State Evaluation score or Montreal Cognitive Assessment Test score. Levodopa-equivalent daily dose and the administered doses of levodopa and other PD medications were evaluated at baseline and after starting LECIG treatment. The efficacy of LECIG in reducing daily hours of off time, motor fluctuations, and dyskinesias were assessed. Any percutaneous endoscopic gastrojejunostomy system or device complications after starting LECIG treatment were noted.

RESULTS

At baseline, patients were taking oral levodopa for a mean of 5.3 times per day, with a high proportion also taking concomitant add-on therapies (dopamine agonists, 86%, monoamine oxidase type-B inhibitors, 53%; catechol-O-methyltransferase inhibitors, 64%). LECIG treatment significantly reduced daily off time versus baseline from 5.7 h/d to 1.7 hours per day ( P < 0.01). Duration and severity of dyskinesias was also significantly reduced versus baseline, and improvements were observed in Hoehn and Yahr Scale scores. LECIG treatment also allowed a significant reduction in the use of concomitant oral medications.

CONCLUSIONS

These findings suggest that LECIG treatment is an effective DAT option in APD that can simplify the treatment regimen.

Levodopa-Entacapone-Carbidopa Intestinal Gel in the Treatment of Advanced Parkinson's Disease: A Single Center Real-World Experience

Levodopa-entacapone-carbidopa intestinal gel infusion is a relatively new treatment option for advanced Parkinson's disease. We aimed to describe and analyze the characteristics of de novo levodopa-entacapone-carbidopa intestinal gel therapy in 20 consecutive patients with advanced Parkinson's disease. We assessed the profile of motor complications by evaluating the following: motor fluctuations, dyskinesias, and the freezing phenomenon at baseline (before the testing period) and before discharge. The treatment significantly reduced the duration of daily hours spent in off time compared with baseline pre-treatment values from a mean of 4.8 ± 0.9 h/day to a mean of 1.4 ± 0.5 h per day (p < 0.001). The duration and severity of peak-dose dyskinesia were also significantly reduced compared with baseline values. Out of the 10 patients who reported freezing, 8 did not present this complication at the pre-discharge assessment. Significant improvements were observed in Hoehn and Yahr scale scores in both the on and off states. The levodopa-entacapone-carbidopa intestinal gel therapy was well tolerated during the follow-up period immediately after initiation. Despite a relatively severe stage of the disease, all patients experienced a significant improvement in motor fluctuations, dyskinesias, and the freezing phenomenon.

Role of exercise in modulating prefrontal cortical activation for improved gait and cognition in Parkinson's disease patients

PURPOSE

This narrative review evaluated the impact of exercise on gait and cognitive functions in patients with Parkinson's disease (PD), focusing on prefrontal cortical (PFC) activation assessed using near-infrared spectroscopy (NIRS).

METHODS

A literature search was conducted in the PubMed and Web of Science databases using keywords such as "Parkinson's disease," "gait," "cognitive functions," "exercise," and "NIRS," focusing on publications from the last decade. Studies measuring PFC activity using NIRS during gait tasks in patients with PD were selected.

RESULTS

The review indicated that patients with PD demonstrate increased PFC activity during gait tasks compared to healthy controls, suggesting a greater cognitive demand for movement control. Exercise has been shown to enhance neural efficiency, thus improving gait and cognitive functions.

CONCLUSION

Exercise is crucial for improving gait and cognitive functions in patients with PD through increased PFC activation. This emphasizes the importance of incorporating exercise into PD management plans and highlights the need for further studies on its long-term effects and the neurobiological mechanisms underlying its benefits, with the aim of optimizing therapeutic strategies and improving patients' quality of life.

Comparison of two types of extension tubes for people with Parkinson's disease in advanced treatment with levodopa-entacapone-carbidopa intestinal gel infusions: a prospective, crossover quality study

BACKGROUND

Within Parkinson's disease (PD) management, a pivotal juncture often arises when individuals with PD (PwP) necessitate advanced therapies to stabilise symptom fluctuations and reduce off-periods, which are intrinsic to living with PD. One such intervention is the infusion of duodenal levodopa-entacapone-carbidopa intestinal gel (LECIG), which confers a more dependable levodopa plasma concentration compared with conventional oral therapy. It involves the insertion of a percutaneous endoscopic gastrojejunostomy (PEG-J) tube, facilitating direct access to the stomach and jejunum. Then, a slender tube extends into the small intestine, facilitating the continuous delivery of LECIG via a portable pump. The PEG-J incorporates an extension tube that permits patients with PD to connect the medication pump.

OBJECTIVE

The objective of this study was to assess and compare two types of extension tubes a standard; a standard tube and the ENFit extension tube.

METHOD

Employing a prospective, crossover design at a single centre in Denmark. Each participant evaluated both extension tubes for 14 days. The primary outcome measure was patient-reported evaluation measures through a nine-item questionnaire using a 5-point Likert scale and 10th open-ended qualitative question.

RESULTS

Of the 12 recruited PwP, 10 successfully completed both testing periods and submitted self-reported questionnaires. The participants, with an average age of 70.3 years, comprised three men and seven women. Among them, five had a spouse or cohabitant, while five lived independently (with one residing in a nursing home). The average duration of PD diagnosis was 16.4 years, with an average of 2.6 years since the implantation of the medication pump. The ENFit tube outperformed the standard tube across all nine evaluation criteria, particularly excelling in terms of usability (items 4-6), safety (item 2) and overall product preference (item 9).

Levodopa-Entacapone-Carbidopa Intestinal Gel Treatment in Advanced Parkinson's Disease: A Single-Center Study of 30 Patients

BACKGROUND

Levodopa-entacapone-carbidopa intestinal gel (LECIG) is a novel device assisted treatment option for advanced Parkinson's disease (PD). It has been available in Finland since 2020. There is paucity of scientific studies considering LECIG treatment in clinical practice.

OBJECTIVES

Objectives of this study were to evaluate the changes in medication, adverse events and early discontinuations of LECIG treatment in real life clinical practice.

METHODS

The records of 30 consecutive patients, who received LECIG between years 2020 and 2022 in Helsinki University Hospital, were retrospectively analyzed. Data considering changes in medication, discontinuations, and adverse events during the first six months of LECIG treatment was collected.

RESULTS

Mean levodopa equivalent daily dose (LEDD) rose significantly between baseline before LECIG and six months with treatment (1230 mg vs. 1570 mg, P = 0.001). Three patients were discarded during nasojejunal tube test phase and seven discontinued the treatment during six-month follow-up. Most common reasons for discontinuation were difficulty in finding suitable infusion rate and neuropsychiatric problems. Safety issues encountered were similar to those reported with levodopa-carbidopa intestinal gel (LCIG) treatment. One case of rhabdomyolysis due to severe dyskinesia during LECIG treatment was observed. Patients were satisfied with the small size of the pump system.

CONCLUSIONS

LEDD seems to increase during the first months of LECIG treatment. When compared to studies on LCIG, safety profile of LECIG appears similar, but early discontinuation rate is higher than expected. However, long-term studies are lacking. Only clear advantage to LCIG appears to be the smaller LECIG pump size.

Impact of Physical Exercise on Levodopa Therapy Across Parkinson's Disease Stages

Background

Levodopa is the gold standard of treatment in Parkinson's disease (PD). Its clinical effect changes as the disease progresses. Wearing off is a frequent first manifestation of motor fluctuations. Some patients with advanced PD report faster wearing off after physical exercise.

Objective

The aim was to assess if pharmacokinetics of levodopa is influenced by physical exercise in patients with different disease advancement.

Methods

22 patients with PD (12 untreated with levodopa and 10 with motor fluctuations) and 7 healthy controls (HC) were included. Plasma samples were collected at 9 fixed timepoints following administration of levodopa/benserazide 200/50 mg for two days: rest day and standardized physical exercise day. Clinical assessment with Unified Parkinson Disease Rating Scale part III (UPDRS III) was performed in fixed timepoints. Liquid chromatography-tandem mass spectrometry was used to measure levodopa concentrations.

Results

No differences between the HC, levodopa naïve and advanced PD groups were observed regarding selected pharmacokinetic parameters. In advanced PD and HC no differences in pharmacokinetic parameters of levodopa with and without effort were observed. In levodopa naïve PD group higher mean residence time after rest than after exercise (168.9±48.3 min vs. 145.5±50.8 min; p = 0.026) was observed. In advanced PD group higher UPDRS III score (14.45±5.5 versus 20.9±6.1 points, p = 0.04) was observed after exercise.

Conclusions

The deterioration of motor status of advanced PD patients after physical effort is not reflected by changes in pharmacokinetics but rather mediated by central mechanisms.

Clinical profile of levodopa-carbidopa-entacapone intestinal gel infusion in patients with advanced Parkinson's disease

INTRODUCTION

Parkinson's disease in its advanced stage is a progressive condition that can be treated with levodopa. The long-term complications of this treatment are difficult to manage. A new device-aided therapy has recently been developed to minimize these effects.

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.

Towards improved access to device-aided therapies in advanced PD: the importance of cooperation of different disciplines

Managing the many issues in advanced Parkinson's disease (PD) requires education, continuous support, and specialized outpatient care involving a variety of allied healthcare professionals. It would be greatly appreciated if general neurologists and professionals from various disciplines who work with people diagnosed with Parkinson's disease (PwP) could remain knowledgeable about the existing therapies and their respective roles within the treatment continuum. The movement disorders specialist and the PD nurse are key actors in the coordination of a targeted and patient-empowering multidisciplinary approach for advanced PD. Affordable and timely access to these therapies for the PwP who may need them is presently a challenge for health systems. Education, training, and support for all the involved stakeholders in the process of PD care may improve quality of life both for PwP and caregivers, and reduce inadequate, expensive, time-consuming, and unsuccessful prolongation of standard medical therapies.

Tools and criteria to select patients with advanced Parkinson's disease for device-aided therapies: a narrative review

This article provides an overview of the various screening and selection tools which have been developed over the past 25 years to identify patients with Parkinson's disease (PD) possibly eligible for device-aided therapies (DATs). For the available screening tools, we describe the target therapies (subtypes of DAT), development methods, validation data, and their use in clinical practice. In addition, the historical background and potential utility of these screening tools are discussed. The challenges in developing and validating these tools are also addressed, taking into account the differences in population, the local health care organization, and resource availability.

Access to device-aided therapies in advanced Parkinson's disease: navigating clinician biases, patient preference, and prognostic uncertainty

Device-aided therapies (DAT), which include deep brain stimulation and pump-based continuous dopaminergic stimulation with either levodopa or apomorphine, are among the major advances in the clinical management of Parkinson's disease (PD). Although DAT are being increasingly offered earlier in the disease course, their classical indication remains advanced PD. Theoretically, every patient should be offered transition to DAT when faced with refractory motor and nonmotor fluctuations and functional decline. Worldwide clinical reality is far from these ideal, and, therefore, question the "real-world" equal opportunity of access to DAT for PD patients with advanced PD-even within a single health care system. Differences in access to care, referral pattern (timing and frequency), as well as physician biases (unconscious/implicit or conscious/explicit bias), and patients' preferences or health-seeking behaviour are to be considered. Compared to DBS, little information is available concerning infusion therapies, as well as neurologists' and patients' attitudes towards them. This viewpoint aims to be thought-provoking and to assist clinicians in moving through the process of DAT selection, by including in their decision algorithm their own biases, patient perspective, ethical concerns as well as the current unknowns surrounding PD prognosis and DAT-related long-term side effects for a given patient.

Non-oral continuous drug delivery based therapies and sleep dysfunction in Parkinson's disease

Continuous drug delivery (CDD) has emerged as a feasible and pragmatic therapeutic option for dopamine replacement therapy in advanced Parkinson's disease (PD). CDD aims to mimic the physiological tonic dopamine release from striatal dopaminergic neurons and thus reduces the severity and duration of motor and non-motor fluctuations partly related to pulsatile levodopa stimulation. Non-motor symptoms and fluctuations are ubiquitous in PD and include sleep dysfunction, a problem that occurs in over 90% of PD patients across all stages, from prodromal to palliative. In this review, we discuss the currently available and in development non-oral dopaminergic CDD strategies with a focus on their efficacy in the treatment of the burdensome sleep dysfunction in PD.

Current and novel infusion therapies for patients with Parkinson's disease

Advanced Parkinson's disease is characterized by periods of poor mobility, dyskinesia and progressive decline in functional independence of the affected person despite the manipulation of levodopa doses and the introduction of supplemental therapies such as catechol-O-methyl transferase inhibitors, monoamine oxidase-B inhibitors and dopamine agonists. The implementation of drug delivery systems allows to bypass problems related to irregular and often unpredictable intestinal absorption of oral levodopa, which significantly affects its bioavailability and contributes to the development and persistence of motor complications. Subcutaneous apomorphine and levodopa/carbidopa jejunal infusion systems have been available for many years and their efficacy is confirmed by randomized studies and long-term experience in many centers worldwide. Recently, a new formulation of levodopa/carbidopa infusion gel that includes the catechol-O-methyl transferase inhibitor Entacapone has been introduced to the market. The use of entacapone allows to reduce total daily dose of administered levodopa. Two different soluble formulations of levodopa/carbidopa (ND0612 and ABBV-951) have completed clinical development, and both can ensure subcutaneous delivery by a portable pump infusion system. ABBV-951 uses a foslevodopa/foscarbidopa formulation, both prodrugs to improve absorption and tolerability. Both systems provide effective improvement of motor complications and are likely to expand the therapeutic options in advanced patients. Future efforts should focus on the earlier detection of patients who are candidates for device-aided therapies, increasing appropriate referral and broadening the availability of these treatments globally.

Impact of Infusion Therapies on Quality of Life in Advanced Parkinson's Disease

A high burden of motor and non-motor parkinsonian symptoms is known to have a significant negative impact on the quality of life (QoL) of people with Parkinson's disease (PD). Effective control of these symptoms with therapies that enable patients to maintain a good QoL is therefore a key treatment goal in PD management. When symptom control can no longer be accomplished with oral or transdermal PD treatment regimens, device-aided therapies (DAT), namely levodopa and apomorphine infusion therapies, and deep brain stimulation, are valuable options to consider. DAT options may also help reduce pill burden and thereby improve compliance with treatment. Since PD therapy relies on symptomatic management, the efficacy and tolerability of any intervention is undoubtedly important, however the impact of different therapies on patient-related outcome measures, in particular health-related QoL, is also a critical consideration for those living with a chronic and disabling condition. This review discusses clinical evidence and ongoing research regarding the QoL benefits of levodopa and apomorphine infusion therapies from studies that have used validated QoL outcome measures. The data suggest that timing of these interventions is important to achieve optimal treatment effects, and that early initiation onto infusion therapies at the point when motor fluctuations emerge, and before patient QoL and functioning have significantly declined, may provide the best long-term outcomes. Healthcare professionals caring for people with PD should therefore discuss all available DAT options with them at an early stage in the course of their disease so they can make informed and timely choices that best suit them, their families and care network.

Continuous subcutaneous levodopa-carbidopa for the treatment of advanced Parkinson's disease: is it an improvement on other delivery?

INTRODUCTION

Parkinson's disease (PD) is the second most common neurodegenerative disease and is growing in prevalence and disability. The standard treatment for PD is oral levo-dopa (LD) with carbidopa (CD). As PD progresses, despite higher doses of LD/CD, plasma levels of LD fluctuate, and may be associated with motor fluctuations and dyskinesia.

AREAS COVERED

The development of two new subcutaneous preparations of LD/CD (ND0612 and ABBV-951) for the treatment of motor fluctuations in PD is described in detail. Both reduce motor fluctuations and dyskinesia with minor infusion site adverse events. A third subcutaneous preparation, DIZ102, is in early-stage development.

EXPERT OPINION

The premise for using continuous release LD in advanced PD is that steady state levels of LD will prevent motor fluctuations/dyskinesia, but this is not the whole story, and will limit the benefits of subcutaneous continuous release LD. With its present pump system ND0612 cannot be used as monotherapy, whereas ABBV-951 can be. Having to combine with oral LD/CD will complicate the use of ND0612. Both ND0612 and ABBV-951 only cause modest reductions in OFF time. It is not clear whether these subcutaneous preparations will have more benefits than the intestinal gel, which also reduces OFF time and dyskinesia.

A review of studies on gut microbiota and levodopa metabolism

Parkinson's disease (PD) is the second most common neurodegenerative disease globally. Levodopa (L-dopa) has been the cornerstone for treating Parkinson's since the 1960s. However, complications such as "wearing-off" and dyskinesia inevitably appear with disease progression. With the further development of microbiomics in recent years, It has been recognized that gut microbiota plays a crucial role in Parkinson's disease pathogenesis. However, Little is known about the impact of gut microbiota in PD treatment, especially in levodopa metabolism. This review examines the possible mechanisms of gut microbiota, such as Helicobacter pylori, Enterobacter faecalis, and Clostridium sporogenes, affecting L-dopa absorption. Furthermore, we review the current status of gut microbiota intervention strategies, providing new insights into the treatment of PD.

The Management of Parkinson's Disease: An Overview of the Current Advancements in Drug Delivery Systems

Parkinson's disease (PD) has significantly affected a large proportion of the elderly population worldwide. According to the World Health Organization, approximately 8.5 million people worldwide are living with PD. In the United States, an estimated one million people are living with PD, with approximately 60,000 new cases diagnosed every year. Conventional therapies available for Parkinson's disease are associated with limitations such as the wearing-off effect, on-off period, episodes of motor freezing, and dyskinesia. In this review, a comprehensive overview of the latest advances in DDSs used to reduce the limitations of current therapies will be presented, and both their promising features and drawbacks will be discussed. We are also particularly interested in the technical properties, mechanism, and release patterns of incorporated drugs, as well as nanoscale delivery strategies to overcome the blood-brain barrier.

Device-Aided Therapies in Parkinson's Disease-Results from the German Care4PD Study

Data on the use of device-aided therapies (DATs) in people with Parkinson's disease (PwP) are scarce. Analyzing data from the Care4PD patient survey, we (1) evaluated application frequency and type of DAT in a larger, nationwide, cross-sectoral PwP sample in Germany; (2) analyzed the frequency of symptoms indicative for advanced PD (aPD) and need for DAT amongst the remaining patients and (3) compared the most bothersome symptoms and need for professional long-term care (LTC) of patients with and without suspected aPD. Data from 1269 PwP were analyzed. In total, 153 PwP (12%) received DAT, mainly deep brain stimulation (DBS). Of the remaining 1116 PwP without DAT, >50% fulfilled at least one aPD criterion. Akinesia/rigidity and autonomic problems were most bothersome for PwP with and without suspected aPD, with more tremor in the non-aPD and more motor fluctuations and falls in the aPD group. To recapitulate, the German DAT application rate is rather low, although a large proportion of PwP fulfills aPD criteria indicating a need for intensified treatment strategies. Many reported bothersome symptoms could be overcome with DAT with benefits even for LTC patients. Thus, precise and early identification of aPD symptoms (and therapy-resistant tremor) should be implemented in future DAT preselection tools and educational trainings.

[Parkinson's disease]

Parkinson's disease (PD) is an unparalleled example of a neurodegenerative disorder that can be effectively managed leading to sustained symptom control and quality of life. The cooperation of neurologists with general practitioners, gastroenterologists, and geriatricians is of increasing importance for an optimized management of PD. New diagnostic criteria for PD and for atypical Parkinsonism, which should be considered in the differential diagnostics, include non-motor symptoms and aim to diagnose these disorders as early as possible. Recent research has shown that there are highly complex and clinically relevant interactions with PD at all levels of the gastrointestinal tract, which have been increasingly better understood and have direct clinical relevance. Novel dopaminergic treatment approaches focus on circumvention of the impaired gastrointestinal tract of PD patients. The management of geriatric PD patients and PD dementia requires specific clinical knowledge. Worldwide, PD has emerged as a model disease for the development of network structures for the treatment of chronic neurological diseases.

Effective Management of "OFF" Episodes in Parkinson's Disease: Emerging Treatment Strategies and Unmet Clinical Needs

Motor complications related to the chronic administration of levodopa and failure to prevent the neurodegenerative disease process counterbalance the pivotal discovery of levodopa as the cornerstone of PD treatment. Excellent motor control is offered early during the course of treatment, but this diminishes as pathological changes in the striatum lead to synaptic dopamine levels becoming completely dependent on exogenous dopamine. This non-physiologic stimulation of dopamine receptors eventually manifests as OFF episodes. As no disease modifying therapy exists for PD that can disrupt these pathological changes, most research and treatment focuses on optimization of dopaminergic stimulation of striatal receptors so that they mimic tonic, physiologic stimulation as closely as possible. Strategies focusing on these challenges have included non-pharmacologic approaches, optimizing levodopa pharmacokinetics, using adjunctive treatments including those with non-dopaminergic mechanisms, and implementing rescue therapies. Device aided therapies, including surgery, are also available. In this review, we will focus on effective management of motor symptoms related to OFF periods, including emerging strategies. Unmet clinical needs will be discussed, including non-motor symptoms, targeted molecular therapies and disease modifying therapy.