OBJECTIVE: To evaluate the effectiveness of entacapone in the management of 
levodopa wearing-off in Parkinson's disease (PD) in a naturalistic, real-life 
setting.
RESEARCH DESIGN AND METHODS: This prospective, open-label, observational study 
included patients with idiopathic PD. Patients were eligible for inclusion if 
they had been taking 3-5 doses of levodopa per day for ≥2 months and had shown 
signs of levodopa wearing-off for ≥1 month. Subjects received entacapone 
(recommended dose: 1 × 200 mg tablet with each levodopa dose) for 28 days. 
Patients were asked to complete a wearing-off questionnaire and the 
eight-question Parkinson's Disease Questionnaire Quality of Life assessment 
(PDQ-8). Activities of daily living (both in the on and off states) were 
assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) part II. 
Clinical Global Impression (CGI) of severity of PD-related symptoms was assessed 
using a modified CGI tool. Patient global assessment of severity of PD symptoms 
was also obtained.
RESULTS: A total of 341 patients were enrolled by 68 physicians across Canada. 
At Day 28, 56.9% of the subjects indicated improvement compared to baseline on 
the modified CGI of change (CGI-C); 21.4% reported no change. Improvements were 
also observed on the UPDRS II and the PDQ-8. Benefit from entacapone appeared to 
be relatively uniform across subgroups (e.g., number of daily levodopa doses, 
use of other anti-PD medications).
STUDY LIMITATIONS: The results of this study may be biased due to factors 
inherent in open-label, community-based trials (e.g., compliance). This is, 
however, reflective of everyday clinical practice.
CONCLUSIONS: In this naturalistic, real-life study, the addition of entacapone 
to levodopa therapy provided benefits in quality of life and activities of daily 
living for a substantial proportion of PD patients experiencing wearing-off.