Efficacy and tolerability of Entacapone versus Cabergoline in parkinsonian patients suffering from wearing-off.

In this 12-wk, multi-center, randomized, open-label, rater-blinded study, efficacy and tolerability of Entacapone (ENT) or Cabergoline (CBG) in conjunction with levodopa were compared in 161 older Parkinson's disease patients with wearing-off. Patients received either ENT, 3 to 5 times daily, or CBG, titrated according to requirements to a maximum of 6 mg/d. A significant decrease of nearly 2 hours in the daily OFF-time (primary efficacy variable) was recorded in both treatment groups. The non-inferiority test failed despite a trend in favor of ENT. Reduction in OFF-time occurred faster in the ENT compared to the CBG treated patients. A decrease of approximately 20% was detected in parts II and III of the UPDRS, with no differences between the groups. Forty-three percent of the patients in the ENT group reported dyskinesias at baseline, and 35% at the final visit. The corresponding figures in the CBG group were 46% and 43%. Quality of life, measured by PDQ-39, increased substantially with both ENT and CBG. The mean daily dosage at the final visit was 698 mg for ENT (plus 447 mg levodopa) and 3.45 mg for CBG (plus 475 mg levodopa). Adverse events (AE), leading to discontinuation, were reported in 8.5% of the ENT and 13.9% of the CBG treated patients. Nausea was the most common AE in each group, corresponding figures being 7.3% with ENT and 25.3% with CBG (P=0.0024). A probable or possible causal relationship with ENT was reported in 41% and with CBG in 64% of the AE. Among these, only one serious AE (dehydration) was recorded with each treatment group. ENT and CBG reduced the patient's motor complications effectively and to a similar degree. The clinical benefit was more quickly apparent with ENT, which also showed a more favorable AE profile than CBG.