Memantine had not been studied in DEP-MCI patients. Since treatment of these patients with combined antidepressant and AChEIs has been associated with cognitive improvement in pilot studies, we explore whether treatment of DEP-MCI with memantine in addition to antidepressant treatment would benefit cognitive performance and lead to a low rate of conversion to dementia. We evaluate the cognitive and antidepressant benefit of combined open-label es-citalopram and memantine treatment over 48 weeks in a DEP-CI sample.