- Subject is currently receiving treatment with any of the following drug classes: neuroleptics, hypnotics, antidepressants, anxiolytic drugs, anticonvulsive therapy, budipine, dopamine antagonist antiemetics (except domperidone), opioids, benzodiazepines, monoamine oxidase (MAO) inhibitors, catechol-O-methyltransferase (COMT) inhibitors, sedative antihistamines, psychostimulates, or amphetamines. If subject has received such therapy, a Washout Period of at least 7 days prior to Baseline (Visit 2) is required before starting treatment in this study