恩他卡朋治疗帕金森病的新进展

儿茶酚-氧位-甲基转移酶（COMT）抑制剂是继左旋多巴（L-dopa）和多巴胺受体激动剂之后推入临床的治疗帕金森病（PD）的一类新药，可抑制外周COMT活性，延长L-dopa的半衰期和药时曲线下面积（AUC），能延长和增加L-dopa的生物利用度，但不影响达峰时间（Tmax）及达峰浓度（Cmax），是长期L-dopa治疗后出现疗效减退和开关现象等并发症时重要的辅助药物。恩他卡Eq（entacapone）被认为是较安全的COMT抑制剂。近几年的研究结果显示，在出现运动波动的PD患者中，恩他卡朋可减少L-dopa剂量，延长“开”期，明显缩短“关”期，并改善UPDRS的运动评分，提高生活质量。     

恩他卡朋添加治疗症状波动的帕金森病的随机、双盲、安慰剂对照临床研究

目的:探讨添加恩他卡朋治疗PD患者剂末现象的疗效和安全性。方法:40例伴有剂末现象的PD患者进行随机、双盲、安慰剂、平行分组临床对照试验。根据患者日记记录的"开"、"关"期时间、UPDRS各部分评分、研究者总体评估变化量表和左旋多巴每日剂量来评定疗效。结果:恩他卡朋治疗12周时能显著延长"开"期时间、缩短"关"期时间,降低UPDRS评分,减少每日左旋多巴用量,研究者主观感觉65%的患者病情好转,与安慰剂组相比差异有显著意义。不良事件的发生率与安慰剂组相比差异无显著意义。结论:添加恩他卡朋治疗伴有剂末现象的PD患者安全、有效。     

Bimodal administration of entacapone in Parkinson's disease patients improves motor control

Catechol- O -methyl transferase (COMT) inhibition by entacapone enhances levodopa absorption and reduces 'off' time in Parkinson's disease (PD). We hypothesized that the administration of entacapone in a bimodal fashion (two doses 1 h apart) would enhance levodopa absorption and improve the motor symptoms of PD. Patients with PD ( n  = 17) were given immediate (IR)- or controlled (CR)-release levodopa each with either one or two doses of entacapone. Bimodal entacapone produced a significant increase in IR and CR levodopa half-life, 'area under the curve' (AUC), and C _max with levodopa CR. For both IR and CR levodopa, bimodal entacapone resulted in a significant improvement in the Unified Parkinson's Disease Rating Scale part III (motor). Bimodal entacapone increased COMT inhibition, improved the pharmacokinetics of levodopa and improved motor scores for 6 to 8 h. Bimodal use of entacapone may be useful in selected patients to improve motor control and implies that controlled release COMT inhibition would be beneficial in PD patients.     

Efficacy and safety of entacapone in Parkinson's disease patients with suboptimal levodopa response: a 6-month randomized placebo-controlled double-blind study in Germany and Austria (Celomen study)

OBJECTIVES: To determine the efficacy and safety of the catechol-O-methyltransferase (COMT) inhibitor entacapone, used as an adjunct to levodopa, in Parkinson's disease (PD) patients. PATIENTS AND METHODS: In this parallel group, randomized, double-blind study, 301 PD patients, the majority with motor fluctuations, received entacapone (200 mg) or placebo with each daily dose of standard or controlled-release (CR) levodopa. The 24-week treatment period was followed by 2 weeks of entacapone withdrawal. Efficacy was determined by home diaries ('on' and 'off' times), Unified Parkinson's Disease Rating Scale (UPDRS) and changes in levodopa dosage, and safety by adverse-event inquiry, vital signs, electro cardiography (ECG) and laboratory tests. RESULTS: In the total population, the UPDRS activities of daily living and motor scores were significantly improved (P < 0.05) by entacapone vs placebo. In fluctuating patients, 'on' time increased (1.7 h) and 'off' time decreased (1.5 h) significantly more with entacapone than with placebo (0.5 and 0.6 h, respectively; P < 0.05), and the daily levodopa dose was reduced by 54 mg with entacapone and increased by 27 mg with placebo (P < 0.05). Entacapone benefit was lost on withdrawal. Entacapone efficacy was comparable between patients using CR and standard levodopa preparations. Increased dyskinesias (entacapone 34%, placebo 26%) and nausea (10 and 5%, respectively), mostly occurring shortly after treatment initiation, were generally managed by reducing the levodopa dose. Diarrhoea (entacapone 8%, placebo 4%) was seldom severe. There were no differences in vital signs, ECG or laboratory results. CONCLUSION: Entacapone is an effective and safe levodopa extender and enhancer, improving the symptomatic efficacy of levodopa in PD and adding to the patients' benefit.     

Treatment of end-of-dose wearing-off in parkinson's disease: stalevo (levodopa/carbidopa/entacapone) and levodopa/DDCI given in combination with Comtess/Comtan (entacapone) provide equivalent improvements in symptom control superior to that of traditional levodopa/DDCI treatment

The aim of this study was to evaluate the efficacy of the new optimised levodopa, Stalevo (levodopa, carbidopa and entacapone) in patients with Parkinson's disease experiencing end-of-dose wearing-off. Treatment with Stalevo was compared to treatment with traditional immediate-release levodopa and dopa-decarboxylase inhibitor (DDCI) formulations along with adjunct entacapone (Comtess/Comtan). A European, open, parallel-group, active treatment-controlled phase IIIb study evaluating 176 patients randomised to switch from their current regimen of levodopa/DDCI to either an equivalent dose of Stalevo or levodopa/DDCI plus entacapone. After 6 weeks, treatments were assessed using the Clinical Global Impression of Change, the Unified Parkinson's Disease Rating Scale and a Motor Fluctuations Questionnaire. Over 70% of patients in both the Stalevo and adjunct entacapone arms felt that they were clinically improved and over 80% experienced a reduction in fluctuations. Although there was no significant difference between Stalevo and levodopa/DDCI plus entacapone with regard to motor improvement and side effects, 81% of patients stated that they preferred treatment with Stalevo compared with taking two separate tablets (i.e. levodopa/DDCI and entacapone). Stalevo was well tolerated and safe when substituted for levodopa DDCI preparations.     

Efficacy of combining levodopa with entacapone on quality of life and activities of daily living in patients experiencing wearing-off type fluctuations

OBJECTIVES: To compare the efficacy of levodopa/dopa decarboxylase inhibitor (DDCI) plus entacapone with levodopa/DDCI plus placebo on measures of parkinsonian disability and health-related quality of life (QoL) in subjects with Parkinson's disease (PD) experiencing motor fluctuations. MATERIALS AND METHODS: A double-blind, placebo-controlled phase IV study was performed in 270 PD patients randomized to receive either entacapone 200 mg or placebo with each dose of their current levodopa regimen. The primary variables were the Unified Parkinson's Disease Rating Scale (UPDRS) part II activities of daily living (ADL) and the Parkinson's Disease Questionnaire (PDQ)-39 summary index. UPDRS parts I, III-VI, Global Assessment of Change, PDQ-39 subscores, and the Short-Form (SF)-36 and the European Quality of Life five-dimension questionnaire (EQ-5D) were included as secondary variables. RESULTS: There was a significant improvement in ADL scores with levodopa/DDCI/entacapone compared with levodopa/DDCI/placebo at 5 and 13 weeks (-2.3 vs -0.7, respectively; P = 0.0001). However, no significant differences were observed between treatments using the PDQ-39 summary index. UPDRS part III (motor) scores significantly decreased in the levodopa/DDCI/entacapone group compared with the levodopa/DDCI/placebo group (-5.0 vs -2.9, respectively; P = 0.03). Similarly, the change in the investigators Global Assessment was significantly greater (P = 0.004) in the levodopa/DDCI/entacapone group. There were no significant differences between treatments for any of the PDQ-39 subscores, the SF-36 variables or the EQ-5D utility score. CONCLUSIONS: Levodopa combined with entacapone demonstrated good efficacy in terms of ADL, global function, motor performance and was well tolerated. However, this short-term study did not generate significant improvements in QoL.     

Conversion from sustained release carbidopa/levodopa to carbidopa/levodopa/entacapone (stalevo) in Parkinson disease patients

OBJECTIVES: This study was performed to determine if conversion from sustained release carbidopa/levodopa (SR-CL) with or without entacapone to carbidopa/levodopa/entacapone (CLE; Stalevo) improves motor functioning and quality of life in Parkinson disease (PD) patients and to assess patient tolerance and drug preference. METHODS: PD patients reporting suboptimal symptom control with SR-CL were converted to CLE. The basic conversion was 1 SR-CL 25/100 to 1 25/100/200 CLE and 1 SR-CL 50/200 to 1 37.5/150/200 CLE with additional changes as necessary. RESULTS: There were 62 patients with an average age of 68 years and an average disease duration of 11 years. CLE was preferred by 42 patients and SR-CL was preferred by 20 patients. In those that preferred CLE, Unified Parkinson Disease Rating Scale (UPDRS) mentation and motor subscores, Parkinson Disease Questionnaire-39 (PDQ-39) quality-of-life activities of daily living (ADL) and bodily discomfort subscores, and Epworth Sleepiness Scale (ESS) scores were significantly improved. There were no significant changes in any measures in the group that preferred SR-CL. Common adverse effects in the group that preferred CLE included nausea, vomiting, increased dyskinesia or off time, dizziness, and somnolence. The most common adverse events in the group preferring SR-CL were increased off time or dyskinesia, nausea, and vomiting. CONCLUSIONS: A majority of patients suboptimally controlled on SR-CL can be successfully converted to CLE with improvements in motor function, quality of life, and sleepiness. Older patients, with longer disease duration not previously exposed to entacapone, may better tolerate CLE after the addition of entacapone.     

Entacapone in the treatment of Parkinson's disease

BACKGROUND: The development of fluctuations in motor response and involuntary movements commonly complicate the treatment of Parkinson's disease (PD). Catechol-O-methyltransferase (COMT) inhibitors delay the breakdown of levodopa, which leads to an increase in levodopa bioavailability and more stable concentrations of plasma levodopa. The addition of a COMT inhibitor therefore combines the rapid onset of levodopa with prolonged efficacy, and theoretically provides a more continuous stimulation of dopamine receptors with reduced risk of motor complications. Randomised, controlled trials have shown that in patients with PD who have motor fluctuations, the addition of the COMT-inhibitor entacapone results in an improvement in motor fluctuations, particularly of the "wearing-off" type, with about 1.0-1.7 h more on-time and less off-time per day, reduced required levodopa dose, modest improvement in motor and disability scores (mean total unified PD rating scale [UPDRS] scores of about 4.5), and in some but not all studies improvement of health-related quality of life [HRQOL] scores. RECENT DEVELOPMENTS: Patients with stable PD, without motor fluctuations, also have improved HRQOL scores on treatment with entacapone in addition to levodopa with a dopa-decarboxylase inhibitor. However, in a recent large multicentre study, UPDRS motor and disability scores were not improved despite significant improvements in HRQOL scores. The disparity between results on clinical rating scales and HRQOL scores suggests that these scales give different and potentially complementary information on health status changes in PD, and that entacapone provides benefit that may not be captured with standard clinical rating scales. Whether entacapone combined with levodopa can delay dyskinesia or motor fluctuations in patients with untreated PD is unknown; however, in animal studies, a decrease in motor complications has been reported in drug-naive animals given frequent doses of levodopa combined with entacapone. WHERE NEXT?: Clinical studies are underway to address the hypothesis that motor complications in PD can be delayed if entacapone is given from the start of treatment. Until the results of these trials are available, entacapone is indicated as a useful adjunct to levodopa in the symptomatic treatment of patients with PD with and without motor fluctuations. In addition, future trials should specifically assess the effect of entacapone on HRQOL in PD.     

Dual dopamine agonist treatment in Parkinson’s disease

We studied the effectiveness of cabergoline as an adjunct in patients with early Parkinson's disease receiving another dopamine agonist (pramipexole or ropinirole), at the maximal permitted dose. The study enrolled 47 patients: 35 had motor fluctuations and were receiving a dopamine agonist with levodopa; and 12, without motor fluctuations, were receiving a dopamine agonist without levodopa. These medications had in all cases failed to achieve adequate symptom control. In the 35 patients with motor fluctuations, when cabergoline was added to therapy, the time spent in the OFF period decreased by 65.6% (from 3.14+/-1.11 to 1.08+/-1.07 hours p<0.0001); and the Unified Parkinson's Disease Rating Scale (UPDRS) motor score decreased by 19.24% (from 41.68+/-12.6 to 33.66+/-10.22; (p<0.0001) during the OFF condition, and by 7.11% (from 17.01+/-6.63 to 15.8+/-7.22; p<0.001) during the ON condition. Nocturnal akinesia improved in all the patients except one. In the 12 patients without motor fluctuations, when cabergoline was added, the UPDRS score improved by 34.4% (from 23.5+/-5.3 to 15.5+/-4.7).This open study shows that dual dopamine agonist therapy can be useful in the symptomatic treatment of patients with early or more advanced Parkinson's disease receiving therapy with or without levodopa.     

Optimizing levodopa therapy for Parkinson's disease with levodopa/carbidopa/entacapone: implications from a clinical and patient perspective

After 40 years of clinical experience, levodopa remains the gold standard treatment for Parkinson's disease (PD) despite the recent emergence of a host of new therapies. Some physicians are cautious when prescribing levodopa because of its association with motor complications. Evidence now suggests that levodopa-associated complications are a result of deep troughs in delivery of levodopa to the brain caused by the short plasma half-life of conventional levodopa formulations (levodopa and a dopa decarboxylase inhibitor [DDCI]). Dosing strategies, such as dose increases and dose fractionation, may be effective in the short term. For the longer-term, levodopa/carbidopa/entacapone provides pharmacokinetically optimized levodopa therapy that significantly increases the plasma half-life and bioavailability of levodopa, providing more consistent plasma levodopa levels without deep troughs. Evidence from clinical trials in PD patients experiencing re-emergence of symptoms due to wearing-off has consistently shown that levodopa/DDCI and entacapone significantly increases ON-time and affords greater functionality, as measured by the Unified Parkinson's Disease Rating Scale (UPDRS) with conventional levodopa. These trials have also shown that levodopa/DDCI and entacapone is generally well tolerated, with notable adverse events including worsening dyskinesia, nausea and diarrhea. Patients experiencing re-emergence of symptoms due to wearing-off may benefit from optimized levodopa therapy with levodopa/carbidopa/entacapone.     

Catechol-O-methyltransferase inhibition with entacapone: Evidence from controlled clinical trials in Parkinson's disease

Adjunct therapy with the catechol-O-methyltransferase inhibitor entacapone is a first-line approach to treat wearing-off type motor fluctuations in levodopa-treated Parkinson's disease (PD) patients. Five randomized placebo-controlled trials including a total of >1000 patients have established its efficacy, showing increases in ON time between 0.7 and 1.6 h, with corresponding OFF-time reductions. These and other trials also found improvements in ON motor function and quality of life. Additional trials have tested the efficacy of adjunct entacapone in patients either without or with early and mild motor fluctuations and also found enhanced motor control and improved activities of daily living function and quality of life, whereas the STRIDE-PD trial failed to show efficacy of early entacapone use in delaying the onset of dyskinesias. Adjunct entacapone enhances dopaminergic activity and may increase levodopa-induced adverse events like dyskinesias, which can usually be controlled by modest levodopa dose reductions. There is no formal requirement to monitor liver function during entacapone treatment. Entacapone can be a rare cause of lymphocytic colitis with severe diarrhoea and need for treatment discontinuation. In 2003, a triple-combination pill of levodopa, carbidopa, and entacapone (LCE) was first introduced onto the market, and since then proprietary LCE (Stalevo^®) is indicated on the basis of those trials for patients with idiopathic PD to (i) substitute for immediate-release carbidopa/levodopa and entacapone previously administered as individual products or (ii) replace immediate-release carbidopa/levodopa therapy (without entacapone) when patients taking a total daily dose of levodopa of ≤600 mg and not experiencing dyskinesias experience signs and symptoms of end-of-dose wearing off.     

Early versus delayed initiation of entacapone in levodopa‐treated patients with Parkinson’s disease: a long‐term,retrospective analysis

Background: We analysed data from three clinical trials in Parkinson’s disease (PD) patients with wearing‐off to determine whether early enhancement of levodopa therapy with entacapone can lead to better long‐term outcomes than delayed entacapone treatment. Methods: Post‐hoc analysis of pooled data from three randomized, double‐blind, placebo‐controlled studies and their long‐term, open‐label extension phases. In all three studies, patients on levodopa/dopa‐decarboxylase inhibitor (DDCI) were first randomized to entacapone (‘early‐start’ group) or placebo (‘delayed‐start’ group) for the initial 6‐month double‐blind phase, after which all patients received open‐label levodopa/DDCI and entacapone treatment for up to 5 years. Results: A total of 488 PD patients with wearing‐off were included in the analysis. A statistically significant benefit of early initiation of levodopa/DDCI and entacapone was found, with an improvement in Unified Parkinson’s Disease Rating Scale Part III (motor) score of ?1.66 (95% confidence intervals [?3.01, ?0.31]) points compared with the delayed‐start treatment group (P < 0.05). Levodopa/DDCI and entacapone therapy was well tolerated. There was no excess of dyskinesia in the early‐start group. Conclusions: These data suggest that early rather than delayed addition of entacapone to levodopa/DDCI in PD patients with wearing‐off provides a modest clinical benefit over levodopa/DDCI that is maintained for up to 5 years.     

Clinical problems in non-fluctuating patients with Parkinson's disease: a community-based study.

OBJECTIVE: To investigate the frequency of nonfluctuators in a community-based prevalence study of Parkinson's disease (PD) and to describe disability, non-motor problems, and health-related quality of life in patients with PD with and without motor fluctuations, and compare the findings to those of two control groups. METHODS: The study involved 245 patients with PD who were participating in a prevalence study and two control groups (100 healthy elderly individuals and 100 patients with diabetes mellitus [DM]). Data were obtained through neurologic examination and a semistructured interview, and by the use of several questionnaires. RESULTS: In this group of unselected patients with PD, 78% did not experience motor fluctuations. Mean duration of treatment with levodopa was 6.3 years. Patients with motor fluctuations had a lower age at onset of disease, longer duration of disease, and a higher daily levodopa dose than patients without fluctuations. Among the non-fluctuating patients, we found more dementia and a higher age at prevalence day. Disability (assessed by the Unified Parkinson's Disease Rating Scale subscales for activities of daily living and motor function and the Hoehn and Yahr stage) was similar in fluctuators and nonfluctuators. Depression, sleep disturbances, and fatigue were equally frequent in both patient groups. The occurrence of these difficulties was clearly more frequent among non-fluctuating patients with PD than among the control subjects. CONCLUSION: Most patients in the general population who have PD do not experience dose-dependent motor fluctuations. Severity of motor disability and neuropsychiatric manifestations are as important in non-fluctuators as in fluctuators. Patients without motor fluctuations have more depression, sleep disturbances, fatigue, and a poorer health-related quality of life than patients with DM and healthy elderly individuals. This also underlines the importance of developing better management and treatment strategies for this group of patients with PD.     

A multicenter Italian randomised study on early treatment of Parkinson disease: comparison of 1-dopa, 1-deprenyl and dopaminoagonists. Study design and short term results

On the long term Parkinson Disease (PD) treatment is often complicated by the occurrence of motor fluctuations. To find out whether early treatment of PD with levodopa, dopaminoagonists or 1-deprenyl is associated with any difference in motor fluctuations occurrence, the Italian Parkinson Study Groups initiated a multicenter, randomized study. Since November 1988, 475 patients cequiring effective treatment for idiopathic PD have been randomized to receive levodopa, dopoamine agonists or deprenyl. After 2 months of therapy, all patients evaluated with the Unified Parkinson Disease Rating Scale showed a significant amelioration. Daily living activities were more impaired in patients treated with deprenyl. Study design is presented and first resuts are discussed.Paper presented at the National Congress at Sorrento in 1991 and selected by the Editorial Board of the Journal.     

Long-term comparative experience with tolcapone and entacapone in advanced Parkinson's disease

The objective of this study was to compare the long-term tolerability and efficacy of tolcapone and entacapone in patients with fluctuating Parkinson's disease (PD). Tolcapone and entacapone are two currently available catechol- O -methyltransferase inhibitors that have demonstrated efficacy in the treatment of advanced PD. There are little published data on long-term experience and no direct comparisons. We compared the results of two separate, simultaneous, long-term open label extensions, one for tolcapone and the other for entacapone. The inclusion/exclusion criteria were similar. Data were collected prospectively at 6, 12, 24, and 36 months. Efficacy measures included the Unified Parkinson's Disease Rating Scale (UPDRS) total score, subscores, items 32 (duration of dyskinesia) and 39 (duration of "off" time), and levodopa dose. The two groups were compared using a Mann-Whitney U test for change from baseline and analysis of variance. Tolerability was defined as the ability of patients to maintain therapy and was compared using a Kaplan-Meier analysis. Eleven patients enrolled in the entacapone study and 14 in the tolcapone study. The tolcapone group had more severe disease with significantly higher UPDRS motor score, duration of "off," and levodopa dose requirement. Tolcapone was more effective in lowering UPDRS motor and complication subscores, duration of "off" time, and levodopa doses. UPDRS motor scores and change in levodopa dose in the tolcapone group remained below baseline level for 36 months; however, they were above baseline in the entacapone group from 6 months on. Tolerability was the same for both treatments. Tolcapone appears to have greater and longer efficacy with regard to motor symptoms, "off" time, and change in levodopa requirements than entacapone. These findings indicate that tolcapone continues to have a place in the treatment of advanced PD. However, the risks associated with this drug, particularly hepatic injury, and the requirement for rigorous blood monitoring, need to be considered when choosing an appropriate treatment for patients with advanced PD.     

Efficacy and safety of levodopa with entacapone in Parkinson's disease patients suboptimally controlled with levodopa alone, in daily clinical practice: an international, multicentre, open-label study

The combination of entacapone with levodopa is effective in the treatment of Parkinson's disease (PD), providing significant improvements in 'on' time and Unified Parkinson's Disease Rating Scale (UPDRS) motor and ADL scores in controlled clinical trials. This multicentre, open-label study was designed to further evaluate the effectiveness of levodopa combined with entacapone 200 mg in routine clinical practice. Patients experiencing end-of-dose wearing-off were treated for 8 weeks (treatment phase), with an optional extension phase up to 20 weeks. The primary efficacy parameter was the Investigators' Global Assessment of Change; secondary efficacy parameters included UPDRS, 'off' time (from patient diaries), Patients' Global Assessment of Change, quality of life (QoL), SF-36 Health Assessment Questionnaire and Parkinson's Disease Questionnaire 39 (PDQ-39). Of the 479 patients who entered this study, 427 (89.1%) completed the treatment phase and 374 (78.1%) continued into the extension phase. Based on the Investigators' Assessment of Change, 380 (79.7%) patients showed an improvement with entacapone during the treatment phase. This improvement was maintained into the extension phase, and at Week 20, 301 (82.2%) patients continued to show an improvement. A positive treatment effect with entacapone was also seen with all secondary efficacy parameters, including QoL. Mean change in the total PDQ-39 scores showed improvements from baseline of -4.0 score points to the end of the treatment phase (n=182) and -3.1 score points at the end of the extension phase (n=152). Entacapone in combination with levodopa was generally well tolerated: 40 patients (8.4%) discontinued treatment due to adverse events (AEs) by the end of the extension phase. This study in a daily clinical practice setting confirmed the efficacy of coadministering entacapone with levodopa shown in controlled clinical trials and suggests that the combination is useful in improving the disability and QoL in patients with PD.     

Long-term effectiveness and quality of life improvement in entacapone-treated Parkinson's disease patients: the effects of an early therapeutic intervention

To evaluate the long-term effects of entacapone on both mean daily 'on' time and health-related quality of life (QoL) in patients with Parkinson's disease (PD) experiencing 'end-of-dose' motor fluctuations and the benefits of an early therapeutic intervention. A prospective, multicenter, observational, 12-month study was performed with an initial 3-month intervention phase, consisting of a phone call to half of the patients from randomly selected investigators to assess if dose adjustment was necessary. Effectiveness was determined by home diaries ('on' time), subscales II and III of the Unified Parkinson's Disease Rating Scale (UPDRS), and the Parkinson's Disease Questionnaire (PDQ-8). After 3 months of treatment, 4.0% of the intervention group patients discontinued the study, versus 18.4% in the control group ( P  < 0.01). The improvement in 'on' time was significantly increased since the 3-month visit (21%, P  < 0.0001) until the end of the study (23% at 12 months, P  < 0.0001). Entacapone also induced significant reductions in the UPDRS scores for subscales II and III and in the PDQ-8 score. 11.2% of patients experienced at least one adverse reaction. This study confirms the effectiveness of entacapone in reducing motor fluctuations by increasing 'on' time, and in improving QoL of PD patients. An early adjustment of entacapone and levodopa doses reduces the number of treatment discontinuations during the first months of treatment.     

Efficacy and tolerability of entacapone in patients with Parkinson's disease treated with levodopa plus a dopamine agonist and experiencing wearing-off motor fluctuations. A randomized,double-blind,multicentre study

The efficacy and tolerability of entacapone was investigated in a randomized, double-blind, placebo-controlled, 3-month study of 162 patients with Parkinson's disease (PD) treated with levodopa and a dopamine agonist and experiencing wearing-off motor fluctuations. Patients were randomized in a 3 : 2 ratio to entacapone 200 mg or placebo, administered with each dose of levodopa. Efficacy was judged on the improvement of "on" and "off" time while awake (Patient Diary and UPDRS part IV Item 39), Investigators' Global Assessment, the SF-36 Health Survey, and changes in levodopa dosages. Patients were monitored for adverse events, laboratory safety and vital signs throughout the study. Improvements in "on" time as assessed using patient diary data showed a trend in favour of entacapone, however these did not reach statistical significance. "Off" time while awake (UPDRS part IV Item 39) showed an improvement of at least one category in 36% of entacapone-treated patients, compared with 22% in the control group (p = 0.0038). The proportion of patients showing an improvement at the Investigators' Global Assessment was significantly higher (p = 0.0006) in the entacapone-treated group of patients. Also, the proportion of patients with a reduction in their daily levodopa dose was significantly higher (p = 0.02) in the entacapone group (28%) compared with placebo (13%). As expected, the most frequent adverse events were dopamine-mediated (dyskinesia: entacapone 31% versus placebo 13%), and harmless urinary discoloration. The modest increase in dyskinesias could be readily managed by levodopa down-adjustment, and, at study end there was no significant difference for the UPDRS "overall dyskinesia score" between entacapone and placebo. In conclusion, although the primary efficacy variable did not reach statistical significance, the present results demonstrate that entacapone provides additional antiparkinsonian benefits to levodopa therapy and is well tolerated in levodopa-treated PD patients experiencing wearing-off motor fluctuations despite adjunct dopamine agonist therapy.     

Amantadine sulfate infusion effect on N30 somatosensory evoked potentials in Parkinson's disease

The purpose of this study was to evaluate the effect of amantadine sulfate infusion on the N30 component of the median nerve short-latency somatosensory evoked potentials (SSEPs) in patients with Parkinson's disease (PD). Twenty patients with advanced PD and severe motor fluctuations received a 6-day course of amantadine sulfate infusion (400 mg/day) plus their usual levodopa medication. Patients were assessed clinically by means of the Unified Parkinson's Disease Rating Scale (UPDRS-III and -IV). SSEPs to median nerve stimulation were recorded from the parietal and frontal regions before and after the 6-day course of amantadine infusion. Mean UPDRS motor score during the ON and OFF phase improved after amantadine infusion, as did motor fluctuations. SSEP changes resulting from amantadine sulfate treatment were observed in the P20-N30 amplitude as follows: Mean P20-N30 amplitudes before and after treatment were 2.15 +/- 1.11 microV and 3.06 +/- 1.19 microV respectively (p = 0.000), whereas mean N30-P40 amplitude increased from 2.7 +/- 1.6 microV to 3.9 +/- 1.3 microV after treatment (p = 0.000). Our results indicate that coincident to its clinical impact, amantadine infusion in patients with PD affects electrophysiologic parameters as well.     

Safety of entacapone and apomorphine coadministration in levodopa-treated Parkinson's disease patients: pharmacokinetic and pharmacodynamic results of a multicenter, double-blind, placebo-controlled, cross-over study.

We investigated whether administration of the catechol-O-methyl transferase (COMT) inhibitor entacapone, at doses of 200 mg and 400 mg, alters the pharmacokinetics of apomorphine in Parkinson's disease patients experiencing severe motor fluctuations. In addition, the pharmacodynamics and safety of entacapone and apomorphine coadministration in these patients were examined. The study followed a three-sequence, three-period, crossover design. Patients were randomly assigned to one of three sequences that included single oral doses of entacapone 200 mg, entacapone 400 mg, and placebo in a predefined order. On 3 separate test days, study treatment was administered before apomorphine. The study evaluations (pharmacokinetics, tapping test, and dyskinesia evaluation [Abnormal Involuntary Movements Scale - AIMS]) were performed on these days. Furthermore, Unified Parkinson Disease Rating Scale (UPDRS) scores were evaluated at baseline and study end. Pharmacokinetic parameters for apomorphine (C(max), AUC, t(max), t(1/2)) were unchanged by the administration of entacapone, and changes in both the tapping test and AIMS score were similar with all treatments (entacapone 200 mg, entacapone 400 mg, and placebo). There was no significant difference in mean total UPDRS scores between baseline and study end. The administration of entacapone did not change the pharmacokinetic or pharmacodynamic effects of apomorphine in these patients or prolong the clinical effect of apomorphine. Thus, apomorphine may be safely administered to patients receiving therapy with levodopa and entacapone, providing a useful addition to treatment for patients with advanced Parkinson's disease.