Context

By 2050, an estimated 135 million people will suffer from dementia globally.1 Caring for those with Alzheimer's disease (AD)—by far the most common form of dementia—is expensive, costing an estimated £23 billion per annum in the UK. As the disease progresses, neuropsychiatric symptoms such as depression, agitation and behavioural disturbance appear. The incidence of these symptoms, which predict institutionalisation and caregiver distress, is high—perhaps affecting as many as 95% of Alzheimer's sufferers.2 ,3

Historically, antipsychotic drugs have been administered for the treatment of agitation and aggression in this context. While there is evidence for modest efficacy for some antipsychotics, …