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.