Depression and apathy are common behavioral symptom of Alzheimer's disease (AD) and antidepressants, despite their role in improving depression have a minimum impact in improving apathy. Agomelatine has been shown to be effective in alleviating depression and reversing treatment emergent apathy.

The purpose of the current pilot study is to determine the efficacy of agomelatine in depressed patients with AD and comorbid apathy.

In this prospective 4 month study, twenty depressed elderly AD patients (age 65-85) who had been treated with SSRI and/or SNRI and shown a partial response to the antidepressant prescribed, in terms of apathy, were switched to agomelatine. Subjects were monitored for depression (Hamilton Rating Scale for Depression, HDRS), cognitive functions (Mini–Mental State Examination, MMSE) and apathy (Neuropsychiatric Inventory –apathy item, NPI-a).

Within groups, differences of HDRS, CSDD, MMSE and NPI-a scores at baseline, 2nd and 4th month of agomelatine treatment were estimated with repeated measure analysis of variance.

Following agomelatine, a numeric but not statistically significant improvement was observed in depression scores (8.2±3.5 vs 7.8±3.1, p=0.234, 7.8±3.1 vs5.8±2.3, p=0.421). A marked improvement in MMSE score was observed at both 2nd (22.2±4.9 vs 20.9± 5.4, p=0.05) and 3rd assessment(22.2±4.9 vs 23.9±4.9, p<0.05). Apathy score was also improved over the consecutive assessments (25.3±5.9 vs 18.6±3.9, p<0.05 and 18.6±3.9 15.5±4.3, p<0.05).

The present study demonstrated a good therapeutic response to agomelatine in elderly AD patients with depression and apathy symptoms in terms of alleviating apathy.