Background: A 12-week randomized controlled trial demonstrated that brexpiprazole is efficacious for treating agitation in patients with dementia due to Alzheimer's disease.

Objective: To assess the long-term safety and tolerability of brexpiprazole for the treatment of agitation associated with dementia due to Alzheimer's disease.

Methods: This 12-week, active-treatment (oral brexpiprazole 2 or 3 mg/day) extension trial ran from October 2018-September 2022 at 66 sites in Europe/US. Patients with agitation in dementia due to Alzheimer's disease in a care facility/community-based setting who completed the randomized trial were eligible (N = 259 enrolled/analyzed for safety; 88.4% completed). Stable Alzheimer's disease medications were permitted. The primary safety endpoint was the frequency and severity of treatment-emergent adverse events (TEAEs). Change in Cohen-Mansfield Agitation Inventory (CMAI) total score was an exploratory efficacy endpoint.

Results: Mean (SD) age was 74.3 (7.6) years, 145 patients (56.0%) were female, and 248 (95.8%) were White. TEAEs were reported by 67 patients (25.9%), most commonly headache (3.5%) and fall (2.3%). Most TEAEs were mild or moderate in severity; 5 patients (1.9%) reported a severe TEAE, including 3 severe falls attributed to tripping, misjudging sitting, or dehydration. Twelve patients (4.6%) discontinued due to TEAEs. No patients died. Mean CMAI total score improved by 9.1 points over 12 weeks.

Conclusions: Considering the randomized and extension trials together, brexpiprazole 2 or 3 mg was generally well tolerated for up to 24 weeks in elderly patients with agitation associated with dementia due to Alzheimer's disease. Patients showed continued improvement in agitation. CLINICALTRIALS.GOV IDENTIFIER: NCT03594123 (registration date: July 11, 2018).