The Medicinal Chemistry of Natural and Semisynthetic Compounds against Parkinson's and Huntington's Diseases.

Among the diseases affecting the central nervous system (CNS), neurodegenerations attract the interest of both the clinician and the medicinal chemist. The increasing average age of population, the growing number of patients, and the lack of long-term effective remedies push ahead the quest for novel tools against this class of pathologies. We present a review on the state of the art of the molecules (or combination of molecules) of natural origin that are currently under study against two well-defined pathologies: Parkinson's disease (PD) and Huntington's disease (HD). Nowadays, very few tools are available for preventing or counteracting the progression of such diseases. Two major parameters were considered for the preparation of this review: particular attention was reserved to these research works presenting well-defined molecular mechanisms for the studied compounds, and where available, papers reporting in vivo data were preferred. A literature search for peer-reviewed articles using PubMed, Scopus, and Reaxys databases was performed, exploiting different keywords and logical operators: 91 papers were considered (preferentially published after 2015). The review presents a brief overview on the etiology of the studied neurodegenerations and the current treatments, followed by a detailed discussion of the natural and semisynthetic compounds dividing them in different paragraphs considering their several mechanisms of action.

Cost-effectiveness of neurostimulation in Parkinson's disease with early motor complications.

BACKGROUND: Recent research efforts have focused on the effects of deep brain stimulation of the subthalamic nucleus (STN DBS) for selected patients with mild-to-moderate PD experiencing motor complications. OBJECTIVES: We assessed the cost utility of subthalamic DBS compared with the best medical treatment for German patients below the age of 61 with early motor complications of PD. METHODS: We applied a previously published Markov model that integrated health utilities based on EuroQoL and direct costs over patients' lifetime adjusted to the German health care payer perspective (year of costing: 2013). Effectiveness was evaluated using the Parkinson's Disease Questionnaire 39 summary index. We performed sensitivity analyses to assess uncertainty. RESULTS: In the base-case analysis, the incremental cost-utility ratio for STN DBS compared to best medical treatment was 22,700 Euros per quality-adjusted life year gained. The time to, and costs for, battery exchange had a major effect on the incremental cost-utility ratios, but never exceeded a threshold of 50,000 Euros per quality-adjusted life year. CONCLUSIONS: Our decision analysis supports the fact that STN DBS at earlier stages of the disease is cost-effective in patients below the age of 61 when compared with the best medical treatment in the German health care system. This finding was supported by detailed sensitivity analyses reporting robust results. Whereas the EARLYSTIM study has shown STN DBS to be superior to medical therapy with respect to quality of life for patients with early motor complications, this further analysis has shown its cost-effectiveness. © 2016 International Parkinson and Movement Disorder Society.

Treatment of advanced Parkinson's disease in the United States: a cost-utility model.

BACKGROUND: As Parkinson's disease (PD) progresses, patients and their families experience substantial health and economic burdens. Because motor fluctuations (also called 'off-time') are linked to poor quality of life and higher healthcare costs, minimizing off-time is an effective strategy for reducing costs associated with PD. OBJECTIVE: To assess the cost utility of rasagiline or entacapone as adjunctive therapies to levodopa versus levodopa/carbidopa/entacapone (LCE) versus standard levodopa monotherapy in patients with advanced PD and motor fluctuations in the US. METHODS: A 2-year stochastic Markov model was utilized to examine the cost effectiveness of treatments of advanced PD. The model assumed that patients transition health status every 4 months. Transition probabilities, including uncertainties, were estimated from clinical trial data. Medical costs, daily drug costs and utility weights were obtained from published literature. RESULTS: Over 2 years, all therapy options showed greater effectiveness than levodopa alone. Rasagiline+levodopa and LCE were cost saving from a payor perspective, while entacapone+levodopa was cost saving from a societal perspective. Mean benefits over 2 years were 0.12 (90% credibility interval [CI] 0.07, 0.18) additional quality-adjusted life-years (QALYs) for rasagiline+levodopa, entacapone+levodopa and LCE, 5.08 (90% CI 3.87, 6.28) additional months with

Cost effectiveness of rasagiline and pramipexole as treatment strategies in early Parkinson's disease in the UK setting: an economic Markov model evaluation.

BACKGROUND: Levodopa is the most effective treatment for the symptoms of Parkinson's disease (PD). However, after an initial period of benefit, several limitations become apparent, including motor complications such as dyskinesia. Dyskinesia can severely affect patients' quality of life and increases healthcare resource use. Thus, delaying the need for levodopa, and therefore the onset of levodopa-induced dyskinesia, is important. OBJECTIVE: The aim of this study was to compare the cost effectiveness, from a UK healthcare payer perspective, of two antiparkinsonian treatment strategies in early PD: first-line monotherapy with rasagiline, a novel monoamine oxidase B inhibitor; and the non-ergoline dopamine receptor agonist pramipexole. METHODS: An economic Markov model was developed as a pragmatic tool to derive comparative information on the effectiveness, utility and costs of these two strategies over a 5-year period. Model input data were obtained from the TEMPO study for rasagiline and from a study by the Parkinson Study Group for pramipexole. Effectiveness outcomes were time to levodopa and time to levodopa-induced dyskinesia. Cost and quality-adjusted life-year (QALY) data were derived from published sources. RESULTS: Rasagiline was the dominant strategy. Compared with pramipexole, use of the rasagiline strategy was estimated to reduce costs by 18% per patient over 5 years and was associated with an additional 10% delay in dyskinesia onset (0.41 years; 95% CI 0.27, 0.55). This strategy was also found to prolong the time to levodopa initiation by 25% through a gain of 0.83 levodopa-free years (95% CI 0.56, 1.1). In addition, use of the rasagiline strategy was found to generate a 5% gain in QALYs over 5 years compared with the pramipexole strategy (3.7 +/- 0.02 vs 3.51 +/- 0.03). Sensitivity analyses confirmed that the model was robust. CONCLUSIONS: Rasagiline represents a cost-effective alternative to pramipexole in the treatment of early PD in the UK.

[Prospective study of the direct and indirect costs of idiopathic Parkinson's disease]. / Prospektive Erfassung der direkten und indirekten Kosten des idiopathischen Parkinson-Syndroms.

Idiopathic Parkinson's disease is a chronic progressive neurodegenerative disorder that remains refractory to curative treatment. Most patients are afflicted for many years, and the disease frequently results in severe physical handicap. Statements on the considerable cost of treatment are largely based on estimates and retrospective studies. To obtain more substantial data, we conducted a 3-year study of the economic aspects. Direct and indirect costs incurred by 117 patients (78 male, mean age 67.5 years) at the Deutsche Klinik für Diagnostik in Wiesbaden, Germany, were prospectively followed. The average cost per patient and month ran to 1007.55. Of that, direct costs amounted to 603.33 (55.9%), with drugs taking up the major share at 480.23. Indirect costs were 404.22 per patient and month, with 76% thereof related to nursing care and the incapacity to earn a living. Cost increased in proportion to Hoehn and Yahr stage, declining again with stages 4 and 5. The data we gathered confirm that Parkinsonism is responsible for sizeable expenses for not only the treating unit but the national economy as a whole.

Clinical and economic results of bilateral subthalamic nucleus stimulation in Parkinson's disease.

BACKGROUND: High frequency stimulation of the subthalamic nucleus (STN) is an alternative but expensive neurosurgical treatment for parkinsonian patients with levodopa induced motor complications. OBJECTIVE: To assess the safety, clinical effects, quality of life, and economic cost of STN stimulation. METHODS: We conducted a prospective multicentre study in 95 consecutive Parkinson's disease (PD) patients receiving bilateral STN stimulation and assessed its effects over 12 months. A double blind randomised motor evaluation was carried out at 3 month follow up, and quality of life, self care ability, and predictive factors of outcome following surgery were assessed. The cost of PD was estimated over 6 months before and after surgery. RESULTS: The Unified Parkinson's Disease Rating Scale (UPDRS) motor score improved by 57% (p<0.0001) and activities of daily living improved by 48% (p<0.0001) at 12 month follow up. Double blind motor scoring improved by 51% at 3 month follow up (p<0.0001). The total PD Quality of Life Questionnaire (PDQL-37) score improved by 28% (p<0.001). The better the preoperative motor score after a levodopa challenge, the better the outcome after STN stimulation. Five patients developed an intracerebral haematoma during electrode implantation with permanent after effects in two. The 6 month costs of PD decreased from 10,087 euros before surgery to 1673 euros after surgery (p<0.0001) mainly because of the decrease in medication. These savings allowed a return on the procedure investment, estimated at 36,904 euros over 2.2 years. CONCLUSIONS: STN stimulation has good outcomes with relatively low risk and little cost burden in PD patients with levodopa induced motor complications.

[Analysis of direct costs in therapy of Parkinson disease]. / Analyse der direkten Kosten in der Parkinson-Therapie.

The increasing prevalence of Parkinson syndrome and its cost-intensive modern therapies make for a growing economic burden. Studies on cost to date have limited validity owing to the various methods employed (retrospective, focus on partial expenses, minimal case numbers, etc.). The present study collected data pertaining to direct costs. Seventy-seven patients were followed for 10 months. They had been outpatients when enrolled in the study. Hospitalization or comparable changes during the course of observation were registered accordingly. The most significant result revealed by the study is that expenses for medication by far take up the biggest share of the direct costs. In the early stage of the disease (H and Y I), the monthly costs of drug treatment amount to 397.67 Euros. With advancing ailment, costs rose to 561.56 Euros in H and Y 2, 588.30 Euros in H and Y 3, 604.86 Euros in H and Y 4, and 645.77 Euros in H and Y 5. (Average costs for disease remedies amount to 25.46 Euros.) Inpatient costs were 13.47 Euros (with DBS, 19.04 Euros). Adjuvants aggregated to 3.50 Euros per month, medical technical diagnostic workup to 18.74 Euros (47.60 Euros including DBS), and medical services to 15.73 Euros.

[Cost analysis in Italy of various strategies for the treatment of Parkinson disease in the advanced phase]. / Analisi dei costi, in Italia, di diverse strategie per il trattamento della malattia di Parkinson in fase avanzata.

OBJECTIVE: To perform a comparative economic evaluation of therapies--L-dopa drugs, subcutaneous infusion of apomorphine and surgical intervention of Deep Brain Stimulation (DBS)--for the treatment of advanced Parkinson's disease (APD) and to verify the level of assistance guaranteed in Italy to patients affected by APD. METHODS: Literature review and Delphi Panel to collect data about the efficacy of the therapies for the treatment of APD and the use of healthcare resources for such therapies. Field survey to investigate financing mechanisms of the therapeutical alternatives in the Italian regions; cost-analysis over five years (NHS perspective); cost-analysis (hospital perspective) for the initial administration of therapeutic alternatives. RESULTS: Literature review shows that the reduction of the "off-periods" is 62% for Apomorphine and 80-90% for DBS compared to traditional therapy. The 5-years economic analysis from the NHS perspective shows that the cost of a patients with APD is [symbol: see text] 58.065 if treated with traditional therapy, [symbol: see text] 36.423 (including infusional pump and the drug) with subcutaneous apomorphine and respectively [symbol: see text] 56.489 and [symbol: see text] 41.379 (depending on reimbursement of electrodes and neurostimulator on top of the DRG tariff) with DBS. The field survey, highlighted that Regions which currently reimburse the infusion pump for apomorphine and the electrodes and neurostimulator for DBS--on top of the DRG tariff--are a very limited number. CONCLUSIONS: Apomorphine and DBS in the treatment of APD show higher efficacy and lower costs compared to traditional therapy.

Evaluation of healthcare utilization and health status of patients with Parkinson's disease treated with deep brain stimulation of the subthalamic nucleus.

OBJECTIVE: To assess the effects on motor functioning, health status and direct medical costs of high-frequency stimulation of the subthalamic nucleus (DBS-STN) in patients with idiopathic Parkinson's disease (PD). In addition, the cost-effectiveness of DBS-STN vs. drug treatment was investigated. METHODS: 16 consecutive patients with PD from two centers (Düsseldorf/Cologne; Kiel) treated by DBS-STN were prospectively evaluated. Clinical evaluations were done at baseline and 1, 3, 6, 12 months following surgery by means of the Unified Parkinson's disease Rating Scale (UPDRS). Health status of PD patients was assessed using the Sickness Impact Profile (SIP) at baseline and 6 months following surgery. Relevant economic data were taken from the medical records and costs (1999) were derived from different German medical economic resources. Costs were determined from the perspective of the health care provider. RESULTS: Following DBS-STN UPDRS scores (subscores and sum score) as well as health status improved considerably in PD patients. The overall SIP score and the physical dimension score (p < 0.009) were significantly different (p < 0.01) six month after surgery compared with baseline values. Mean costs of DM 40,020 (US dollars 20,810, EURO 20,410, GB pounds 12,810) per patient were spent during the 12 month observation period for in-patient and out-patient care. These expenses included already the costs for the electronic device for bilateral stimulation. Following DBS-STN medication was considerably reduced. Mean daily drug costs at baseline were DM 46.7+/-21.8 (US dollars 24, EURO 24, GB pounds 15) and DM 18.3+/-17.7 (US dollars 10, EURO 9, GB pounds 6) at 12 months following DBS-STN. Accounting for the decreased drug consumption, total annual costs amounted to DM 31,400 (US dollars 16,330, EURO 16,010, GB pounds 10,050). Further, we estimated the incremental cost effectiveness as DBS-STN had higher costs but was more effective than baseline treatment. The incremental total cost-effectiveness ratio for DBS-STN was DM 1.800 (US dollars 940, EURO 920, GB pounds 580) for one point decrease of the UPDRS. CONCLUSION: DBS-STN is an effective treatment that considerably alleviates the severity of signs and symptoms and improves the health status of patients with PD. Compared with drug treatment, however, the expenditures associated with DBS-STN are increased when only direct medical costs are considered in a one year horizon. However, on a long-term basis costs will decrease considerably because of the reduction of the drug expenditure and improved functioning in all activities of daily living. To adequately evaluate the cost-effectiveness of DBS-STN compared with standard drug regimen for PD it is necessary to include direct, indirect and intangible costs on a long-term basis and under standardized circumstances.

Cost-effectiveness analysis of entacapone in Parkinson's disease: a Markov process analysis.

OBJECTIVE: The objective of this study was to examine the cost-effectiveness of a complementary treatment with entacapone versus usual care only in patients with Parkinson's disease. METHODS: The setting for this study was the Netherlands. A Markov process model was constructed to model the average quality-adjusted life years (QALYs) and the costs of both treatments. The model examined a period of 5 years in order to capture the influence of symptom improvement and disease progression. Data for the construction of the model were derived from published literature, including large, multicenter, randomized clinical trials in patients with end-of-dose motor fluctuations. Costs were obtained from published sources. RESULTS: The results of the baseline analysis showed that the use of entacapone as complementary therapy in Parkinson's disease slightly decreased the total average discounted costs from NLG 111,317 to NLG 110,038, while effectiveness increased from 2.42 to 2.56 QALYs (a 6% increase). In addition, entacapone substantially increased time without severe fluctuations by 0.63 years. Sensitivity analyses confirmed the robustness of these findings. CONCLUSION: The study shows that entacapone is a cost-effective treatment in patients with Parkinson's disease: entacapone yields higher effectiveness in terms of both effectiveness measures (time without severe fluctuations and QALYs), while costs remain quite similar to those for usual care. The additional drug costs for entacapone are offset by reductions in other costs.

[Cost of illness in Parkinson disease. A retrospective 3-month analysis of direct costs]. / Krankheitskosten der Parkinson-Erkrankung. Eine retrospektive dreimonatige Analyse der direkten Kosten.

Parkinson's disease (PD) causes significant expense for the national health care system due to its chronic progressive course, the duration of the disease, the high prevalence and the devastating prognosis. In Germany more than DM 320 million are spent for drugs to alleviate parkinsonian symptoms. The aim of this study was to calculate the economic burden of PD by assessing direct medical costs. Forty patients suffering from idiopathic PD were interviewed at an office of neurological specialists and at an outpatient movement disorder clinic about their use of health care resources 3 months prior to the study. The total annual costs reported were DM 14,500, consisting of DM 6500 for drug therapy and DM 8000 for other medical services, including hospital inpatient care (DM 5600), outpatient care (DM 700), medical sundries (DM 1100) and physiotherapy (DM 600). The costs were positively correlated to the extent of the disease (Hoehn and Yahr stage; HY) and the occurrence of motor fluctuations/dyskinesias. We found that both drug-therapy expenses and total medical costs doubled from HYI to HYIV. The rarely employed s.c. therapy with apomorphine additionally increased the costs of drug therapy in HYV. The occurrence of fluctuations/ dyskinesias also increased medical expenses by approximately a factor of two. Indirect burden due to increased days off of work, unemployment and earlier retirement are also significant in Parkinson's disease. This study includes that a treatment which could prevent or retard disease progression as well as a treatment that delays or reduces motor complications would not only ameliorate the situation of patients suffering from PD, but would also lead to significant reductions in cost for the national health care system.