Nabilone for Agitation in Frontotemporal Dementia

Overview

The primary goal of this study is to test the hypothesis that oral nabilone treatment will reduce agitation compared with placebo in patients with Frontotemporal Dementia (both behavioural variant frontotemporal dementia and primary progressive aphasia). The study population is defined as patients with probable Frontotemporal Dementia that meet the International Psychogeriatric Association criteria for agitation in cognitive disorders.

While the search for disease modifying treatment of frontotemporal dementia (FTD) remains elusive, on a day-to-day basis, clinicians struggle to help manage the severe neuropsychiatric symptoms of FTD. Agitation, irritability and aggression are common features of the behavioral variant of FTD and to a lesser extent in primary progressive aphasia, and these symptoms are strongly linked to care partner burden. Unfortunately, current pharmacological options for neuropsychiatric symptoms have limited efficacy. Agitation, aggressive behaviors and irritability in FTD are usually pharmacologically managed with a trial-and-error approach using a combination of trazodone, selective serotonin reuptake inhibitors, antiepileptic drugs, memantine and frequently, antipsychotics. Unfortunately, current pharmacological treatment options for neuropsychiatric symptoms of FTD have limited efficacy and are often based on small case studies or anecdotal evidence. Trazodone has the most support from randomized control trials, but shows limited effectiveness. Therefore, in clinical practice second-generation ('atypical') antipsychotics are commonly used despite a paucity of scientific evidence in FTD. This practice is problematic as antipsychotic use in dementia bears a significant burden of side-effects, including falls, and increased cerebrovascular accidents and mortality. There is a clear need for new treatments using novel mechanisms for neuropsychiatric symptoms in FTD. One promising candidate is nabilone, a synthetic cannabinoid that has shown benefit for agitation in Alzheimer's disease. Nabilone further has potentially beneficial properties on oxidative stress and inflammation in neurodegenerative diseases, mechanisms that have been linked to the pathophysiology of FTD. We propose to conduct the first randomized clinical trial of nabilone for agitation, irritability, and aggression in FTD to obtain data on real-life effectiveness and tolerability. There is a need to obtain data on the efficacy of nabilone on a wide variety of neuropsychiatric symptoms beyond agitation in FTD, while also ensuring the safety of the medication (e.g., is there a detrimental effect on apathy and hyperorality, which are common in FTD). We require data on dosing and tolerability in this population, which is younger on average than Alzheimer's disease subjects from previous studies and therefore may tolerate higher doses of nabilone. The objective of this trial is to obtain robust evidence for the effectiveness and tolerability of nabilone in FTD.