ACHE and Cognitive impairment: Pimavanserin improved the change from baseline to week 6 Scale for the Assessment of Positive Symptoms for Parkinson's Disease Psychosis score and Clinical Global Impressions—Global Improvement score, relative to placebo, in patients with cognitive impairment (baseline MMSE score, 21–24) and those without (baseline MMSE score, ≥25) and in patients with and without concomitant use of acetylcholinesterase inhibitors or memantine (39).