Screened subjects who agreed to participate in the study, taking Levodopa/Benserazide LDB (Madopar®) entered a 4 weeks period with stable regimen of Madopar® (run-in period). The formulations of levodopa admitted in the trial were: Madopar® 100+25; and 200+50 (1/2 or 1 tablet). Following the run-in period, there were two key phases of the study: two maintenance periods (4 weeks each), for a total duration of 8 weeks. Patients were assigned randomly (1:1) by a computerized randomization system to one of two formulation sequences maintaining the dose stabilized during the run in: