Approximately 50% of patients with Parkinson's disease experience 'off time' - abnormal involuntary movements associated with both levodopa therapy and the disease itself. Entacapone, a selective reversible inhibitor of catechol-O-methyltransferase, has been approved for use in the US and the European Union as adjunctive therapy to levodopa and carbidopa in patients with Parkinson's disease. Use of entacapone provides patients with immediate symptomatic relief and enables a 10-12% reduction in the dosage of levodopa. In addition, entacapone has been shown to significantly reduce 'off time' by 17-22%. A study evaluating the cost effectiveness of entacapone in patients with Parkinson's disease was presented at a poster session held at the ISPOR*3rd Annual European Conference [Antwerp, Belgium; November 2000], and is the focus of this report.