The presence of psychotic symptoms in Alzheimer's patients may predict stronger therapeutic response to certain interventions, fundamentally altering how clinicians approach treatment selection. This finding could help identify which patients are most likely to benefit from specific pharmacological approaches to behavioral symptoms.
A pooled analysis of 607 Alzheimer's patients from two Phase 3 trials revealed that brexpiprazole demonstrated significantly greater efficacy in reducing agitation when psychotic symptoms were present. Patients with concurrent delusions or hallucinations experienced a 9.18-point improvement on the Cohen-Mansfield Agitation Inventory compared to placebo, representing a moderate effect size (Cohen's d=0.52). In contrast, patients without psychotic features showed a smaller 4.22-point improvement with a smaller effect size (Cohen's d=0.29).
This differential response pattern suggests distinct neurobiological pathways underlying agitation in Alzheimer's disease. The enhanced efficacy in psychotic presentations likely reflects brexpiprazole's dopamine-serotonin system activity, which may be more relevant when psychotic symptoms indicate broader neurotransmitter dysregulation. This represents a meaningful advance in precision medicine for dementia care, where behavioral interventions have historically followed a one-size-fits-all approach.
However, the analysis was exploratory and post hoc, limiting definitive clinical recommendations. The 23.4% prevalence of concurrent psychosis in this cohort may not reflect real-world populations. Future prospective studies specifically designed to test this hypothesis could establish whether psychotic symptoms should formally guide brexpiprazole prescribing decisions, potentially improving outcomes while reducing unnecessary medication exposure in less responsive patient subgroups.