Treatment of Hallucinosis/Psychosis in Parkinson's Disease by an Investigational Drug

This is a Phase 2, multi-center, randomized, placebo-controlled, double-blind trial of four weeks of ACP-103 treatment of psychosis in Parkinson's disease, with four weeks follow-up. A total of 60 patients meeting entrance criteria will be randomly assigned to receive placebo (30 patients) or active drug (30 patients). Subjects will take study drug daily starting on Day 1. Dose escalations can occur on Study Days 8 and 15 only, and patients will receive a stable daily dosage from Day 16 until Day 28. Single step dose reductions are allowed during that period for adverse events or intolerance. Patients will be evaluated at screening/baseline and at Study Days 1, 8, 15, 28, and 57 by raters blinded to the treatment. The major response variable will be motoric tolerability. Secondary response variables will be efficacy against psychosis and safety. Currently, there are no approved drugs for this indication in the United States. Psychotic symptoms in Parkinson's disease patients are almost always stable, often non-threatening, and rarely paranoid or violent in content. The trial includes the requirement that each patient enrolled has a reliable caretaker who will accompany the patient to each visit who can reliably report on the patient's daily level of function. These factors argue for the safe inclusion of a four-week period of placebo treatment.