Abstract

Background
Delayed ON is a condition in which Parkinson's disease (PD) patients do not experience the effect of levodopa in time after taking the dosage. The efficacy of various oral levodopa regimens to overcome this problem has been investigated limitedly.
Objective
To evaluate the efficacy of levodopa/benserazide dispersible tablet in PD patients with delayed ON to first morning dose.
Methods
This multicenter, randomized, cross-over trial involved 40 eligible PD patients with delayed ON. Participants were randomized to receive either levodopa/benserazide 100mg dispersible or regular tablets for 4 weeks, thereafter one week wash-out interval, followed by an alternate drug for another 4-week. Participants took the investigational drug with the first-morning dose of their antiparkinsonian medications. Other medications were unchanged during the trial. The primary outcome was changes in time-to-ON after the first-morning dose recorded in a special diary before and after each therapy. We also evaluated changes in parkinsonism, motor fluctuations, and dyskinesia using the Unified PD Rating Scale and Unified Dyskinesia Rating Scale. Finally, we investigated whether the efficacy wase affected by Helicobacter pylori status using baseline serum samples from every participant.
Results
Nine patients dropped out during the trial. The time-to-ON was significantly reduced by the dispersible tablet compared with the regular tablet (-34.72 vs -23.81 minutes, p=0.014). There were no significant changes in parkinsonian severity or dyskinesia with either drug. The dispersible formulation was beneficial for both Helicobacter pylori-positive and -negative groups.
Conclusion
Levodopa/benserazide dispersible formulations can improve time-to-ON without exacerbating dyskinesia in PD patients suffering from delayed ON.

• Keywords: Parkinson's disease, dispersible tablet, delayed on, randomized trial, levodopa/benserazide