This is a multi-center, double-blind, placebo-controlled, randomized withdrawal study to evaluate the efficacy and safety of AXS-05 compared to placebo in the treatment of agitation symptoms in subjects with agitation associated with Alzheimer's disease.

Enrolled patients will first enter a 9-week, open-label stabilization period, during which they will be treated with AXS-05 and monitored for a treatment response. Patients who experience a treatment response during the stabilization period will then be randomized into the double-blind treatment period, in a 1:1 ratio, to continue treatment with AXS-05 or to switch to placebo, for up to 26 weeks or until a relapse of agitation occurs.

Inclusion Criteria:

• Diagnosis of probable Alzheimer's disease (AD) based on the 2011 National Institute on Aging-Alzheimer Association (NIA-AA) criteria.
• Diagnosis of clinically signification agitation resulting from probable AD according to the International Psychogeriatric Association (IPA) provisional definition of agitation.

Exclusion Criteria:

• Patient has dementia predominantly of non-Alzheimer's type.
• Patient has symptoms of agitation that are not secondary to AD (e.g., pain, other psychiatric disorder or delirium due to a metabolic disorder, systemic infection, or substance-induced).
• Unable to comply with study procedures.
• Medically inappropriate for study participation in the opinion of the investigator.