Abstract
PURPOSE: Patients with Alzheimer's dementia may experience co-occurring agitation and psychosis symptoms. This exploratory post hoc analysis aimed to analyze the efficacy and safety of brexpiprazole for agitation in patients with Alzheimer's dementia with and without co-occurring psychosis. PARTICIPANTS AND METHODS: Data were pooled from two Phase 3, 12-week, randomized, double-blind, placebo-controlled, fixed-dose trials of brexpiprazole versus placebo in participants with Alzheimer's dementia and agitation, conducted in Europe, Russia, and the US (ClinicalTrials.gov identifiers: NCT01862640, NCT03548584). Post hoc, participants were stratified into subgroups with or without co-occurring psychosis at baseline, defined as a score ≥4 on the Neuropsychiatric Inventory Delusions domain, Hallucinations domain, or both. Efficacy was assessed by the Cohen-Mansfield Agitation Inventory Total score. Safety was assessed by treatment-emergent adverse events (TEAEs). RESULTS: 142/607 participants (23.4%) had co-occurring psychosis at baseline. Brexpiprazole 2 or 3 mg/day was associated with greater improvement in agitation compared with placebo in participants with co-occurring psychosis (least squares mean difference at Week 12, -9.18 [95% confidence interval -15.2 to -3.12]; P=0.004; Cohen's d=0.52) and in participants without co-occurring psychosis (-4.22 [-6.91 to -1.54]; P=0.002; Cohen's d=0.29). In participants with co-occurring psychosis, for brexpiprazole and placebo respectively, 52.9% and 40.0% had TEAEs, and 3.4% and 9.1% discontinued due to TEAEs. No deaths occurred among participants with co-occurring psychosis. In participants without co-occurring psychosis, for brexpiprazole and placebo respectively, 49.3% and 38.2% had TEAEs, and 5.5% and 2.6% discontinued due to TEAEs. Two participants without co-occurring psychosis died; neither death was considered related to brexpiprazole treatment. CONCLUSION: In this post hoc analysis, brexpiprazole improved agitation and was generally well tolerated in patients with Alzheimer's dementia with and without co-occurring psychosis. These exploratory data suggest that brexpiprazole may be of value to patients with Alzheimer's dementia who present with agitation and psychosis in clinical practice.