Entacapone is frequently used together with levodopa/carbidopa (LC) and 
levodopa/benserazide (LB) in the treatment of Parkinson's disease (PD) patients 
with wearing-off symptoms. It is generally assumed that the effects of 
entacapone are independent of the type of decarboxylase inhibitor used, but 
there is very little published data available on the efficacy of entacapone 
administered with LB versus LC. We have performed a pooled analysis of three 
randomized, double-blind, 6-month, phase III studies to compare the treatment 
effects of entacapone (compared to placebo) in PD patients receiving LC or LB. A 
total of 551 PD patients experiencing wearing-off were included in the analysis. 
300 patients were on LB and 251 on LC at baseline. At 6 months, entacapone 
(compared to placebo) improved mean daily OFF-time in patients on LB and LC by 
0.76 (p = 0.016) and 0.95 (p = 0.011) hours, respectively. The corresponding 
improvements in ON-time were 0.97 (p = 0.002) and 0.83 h (p = 0.022), 
respectively. The treatment effects of entacapone both in LB and LC users were 
statistically significant (p < 0.05) also in UPDRS II and III scores, except in 
UPDRS II scores in patients receiving LC (p = 0.20). None of the treatment 
effects of entacapone were statistically significantly different between 
patients receiving LB or LC. Reported adverse events were comparable between LB 
and LC users. We conclude that entacapone provided comparable benefits in PD 
patients with wearing-off symptoms using either LB or LC.